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+The Project Gutenberg eBook, Marine Protozoa from Woods Hole, by Gary N.
+Galkins
+
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+
+
+
+Title: Marine Protozoa from Woods Hole
+       Bulletin of the United States Fish Commission 21:415-468, 1901
+
+
+Author: Gary N. Galkins
+
+
+
+Release Date: May 5, 2006  [eBook #18320]
+
+Language: English
+
+Character set encoding: UTF-8
+
+
+***START OF THE PROJECT GUTENBERG EBOOK MARINE PROTOZOA FROM WOODS HOLE***
+
+
+E-text prepared by Ronald Calvin Huber, while serving as Penobscot Bay
+Watch, Rockland, Maine, and Joseph E. Loewenstein, M.D.
+
+
+
+Note: Project Gutenberg also has an HTML version of this
+      file which includes the original illustrations.
+      See 18320-h.htm or 18320-h.zip:
+      (https://www.gutenberg.org/dirs/1/8/3/2/18320/18320-h/18320-h.htm)
+      or
+      (https://www.gutenberg.org/dirs/1/8/3/2/18320/18320-h.zip)
+
+
+
+
+
+Contributions from the Biological Laboratory of the U. S. Fish
+Commission, Woods Hole, Massachusetts.
+
+MARINE PROTOZOA FROM WOODS HOLE.
+
+by
+
+GARY N. GALKINS,
+Department of Zoology, Columbia University.
+
+_Bulletin of the United States Fish Commission_ 21:415-468, 1901
+
+
+
+
+
+
+Comparatively little has been done in this country upon marine
+Protozoa. A few observations have been made by Kellicott, Stokes, and
+Peck, but these have not been at all complete. With the exception of
+Miss Stevens's excellent description of species of _Lichnophora_ I
+am aware of no single papers on individual forms. Peck ('93 and '95)
+clearly stated the economic position of marine Protozoa as sources of
+food, and I need not add to his arguments. It is of interest to know
+the actual species of various groups in any locality and to compare
+them with European forms. The present contribution is only the
+beginning of a series upon the marine Protozoa at Woods Hole, and
+the species here enumerated are those which were found with the algæ
+along the edge of the floating wharf in front of the Fish Commission
+building and within a space of about 20 feet. Many of them were
+observed in the water and algæ taken fresh from the sea; others
+were found only after the water had been allowed to stand for a few
+days in the laboratory. The tow-net was not used, the free surface
+Protozoa were not studied, nor was the dredge called into play. Both
+of these means of collecting promise excellent results, and at some
+future time I hope to take advantage of them.
+
+My observations cover a period of two months, from the 1st of July
+to the 1st of September. During that time I was able to study and
+describe 72 species representing 55 genera, all from the limited
+space mentioned above. In addition to these there are a few genera
+and species upon which I have insufficient notes, and these I shall
+reserve until opportunity comes to study them further.
+
+I take this opportunity to express my thanks to Dr. Hugh M. Smith
+for many favors shown me while at Woods Hole.
+
+In dealing with these marine forms from the systematic standpoint,
+two courses are open to the investigator. He may make numerous new
+species based upon minor differences in structure, or he may extend
+previous descriptions until they are elastic enough to cover the
+variations. The great majority of marine protozoa have been described
+from European waters, and the descriptions are usually not elastic
+enough to embrace the forms found at Woods Hole. I have chosen,
+however, to hold to the conservative plan of systematic work, and to
+make as few new species as possible, extending the older descriptions
+to include the new forms.
+
+The different classes of Protozoa, and orders within the classes,
+are distributed more or less in zones. Thus the Infusoria, including
+the Ciliata and the Suctoria, are usually littoral in their habitat,
+living upon the shore-dwelling, or attached, water plants and upon
+the animals frequenting them. It is to be expected, therefore,
+that in forms here considered there should be a preponderance of
+Infusoria. Flagellated forms are also found in similar localities,
+but on the Surface of the sea as well; hence the number described
+in these pages is probably only a small proportion of the total
+number of Mastigophora in this region. The Sarcodina, including the
+Foraminifera and the Radiolaria, are typically deep-sea forms and
+would not be represented by many types in the restricted locality
+examined at Woods Hole. Two species, _Gromia lagenoides_ and
+_Truncatulina lobatula_, alone represent the great order of
+Foraminifera, while the still larger group of Radiolaria is not
+represented at all.
+
+The Protozoa described are distributed among the different orders as
+follows:*
+
+
+Class SARCODINA.
+   Subclass RHIZOPODA.
+      Order AMOEBIDA.
+            1. _Amoeba guttula_ Duj
+            2. _Amoeba_ sp.
+            3. _Trichosphærium sieboldi_ Schn.
+      Order RETICULARIIDA.
+         Suborder IMPERFORINA.
+            4. _Gromia lagenoides_ Gruber.
+         Suborder PERFORINA.
+            5. _Truncatulina lobatula_ Walker & Jacob.
+   Subclass HELIOZOA.
+      Order APHROTHORACIDA.
+            6. _Actinophrys sol_ Ehr.
+      Order CHLAMYDOPHORIDA.
+            7. _Heterophrys myriapoda_ Archer.
+Class MASTIGOPHORA.
+   Subclass FLAGELLIDIA.
+      Order MONADIDA.
+            8. _Mastigamoeba simplex_, n. sp.
+            9. _Codonoeca gracilis_, n. sp.
+           10. _Monas_ sp.
+      Order CHOANOFLAGELLIDA.
+           11. _Monosiga ovata_ S. Kent.
+           12. _Monosiga fusiformis_ S. Kent.
+           13. _Codonosiga botrytis_ (Ehr.) J. Cl.
+      Order HETEROMASTIGIDA.
+           14. _Bodo globosus_ Stein.
+           15. _Bodo caudatus_ (Duj.) Stein.
+           16. _Oxyrrhis marina_ Duj.
+      Order EUGLENIDA.
+           17. _Astasia contorta_ Duj.
+           18. _Anisonema vitrea_ Duj.
+      Order SILICOFLAGELLIDA.
+           19. _Distephanus speculum_ Stöhr.
+   Subclass DINOFLAGELLIDIA.
+      Order ADINIDA.
+           20. _Exuviælla lima_ Clenk.
+           21. _Exuviælla marina_ Clenk.
+      Order DINIFERIDA.
+           22. _Gymnodinium gracile_ Bergh.
+           23. _Glenodinium cinctum_ Ehr.
+           24. _Glenodinium compressa_, n. sp.
+           25. _Peridinium digitale_ Pouchet.
+           26. _Peridinium divergens_ Ehr.
+           27. _Ceratium tripos_ Nitsch.
+           28. _Ceratium fusus_ Ehr.
+           29. _Amphidinium operculatum_ Clap. & Lach.
+Class INFUSORIA.
+   Subclass CILIATA.
+      Order HOLOTRICHIDA.
+         Family ENCHELINIDÆ.
+           30. _Lacrymaria lagenula_ Cl. & Lach.
+           31. _Lacrymaria coronata_ Cl. & Lach.
+           32. _Trachelocerca phoenicopterus_ Cohn.
+           33. _Tiarina fusus_ Cl. & Lach.
+           34. _Mesodinium cinctum_, n. sp.
+         Family TRACHYLINIDÆ.
+           35. _Lionotus fasciola_ Ehr.
+           36. _Loxophyllum setigerum_ Quenn.
+         Family CHLAMYDODONTIDÆ.
+           37. _Nassula microstoma_ Cohn.
+           38. _Chilodon cucullulus_ Müll.
+           39. _Dysteria lanceolata_ Cl. & Lach.
+         Family CHILIFERIDÆ.
+           40. _Frontonia leucas_ Ehr.
+           41. _Colpidium colpoda_ Ehr.
+           42. _Uronema marina_ Duj.
+         Family PLEURONEMIDÆ.
+           43. _Pleuronema chrysalis_ Ehr.
+           44. _Pleuronema setigera_, n. sp.
+           45. _Lembus infusionum_, n. sp.
+           46. _Lembus pusillus_ Quenn.
+         Family OPALINIDÆ.
+           47. _Anoplophrya branchiarum_ Stein.
+      Order HETEROTRICHIDA.
+         Family BURSARIDÆ.
+           48. _Condylostoma patens_ Müll.
+         Family HALTERIDÆ.
+           49. _Strombidium caudatum_ From.
+         Family TINTINNIDÆ.
+           50. _Tintinnopsis beroidea_ Stein.
+           51. _Tintinnopsis davidoffi_ Daday.
+      Order HYPOTRICHIDA.
+         Family PERITROMIDÆ.
+           52. _Peritromus emmæ_ Stein.
+         Family OXYTRICHIDÆ.
+           53. _Epiclintes radiosa_ Quenn.
+           54. _Amphisia kessleri_ Wrzes.
+         Family EUPLOTIDÆ.
+           55. _Euplotes charon_ Ehr.
+           56. _Euplotes harpa_ Stein.
+           57. _Diophrys appendiculatus_ Stein.
+           58. _Uronychia setigera_, n. sp.
+           59. _Aspidisca hexeris_ Quenn.
+           60. _Aspidisca polystyla_ Stein.
+      Order PERITRICHIDA.
+         Family LICHNOPHORIDÆ.
+           61. _Lichnophora macfarlandi_ Stevens.
+         Family VORTICELLIDÆ.
+           62. _Vorticella marina_ Greeff.
+           63. _Vorticella patellina_ Müller.
+           64. _Zoothamnium elegans_ D'Udek.
+           65. _Cothurnia crystallina_ Ehr.
+           66. _Cothurnia nodosa_ Cl. & Lach.
+           67. _Cothurnia imberbis_ Ehr.
+   Subclass SUCTORIA.
+         Family PODOPHRYIDÆ.
+           68. _Podophrya gracilis_, n. sp.
+           69. _Ephelota coronata_ Wright.
+         Family ACINETIDÆ.
+           70. _Acineta divisa_ Fraip.
+           71. _Acineta tuberosa_ Ehr.
+         Family DENDROSOMIDÆ.
+           72. _Trichophrya salparum_ Entz.
+
+* This classification includes only the orders and families
+  represented at Woods Hole
+
+
+
+Genus AMOEBA Auct.
+
+The pseudopodia are lobose, sometimes absent, the body then
+progressing by a flowing movement; the body consists of ectoplasm and
+endoplasm, the latter being granular and internal, the former hyaline
+and external. There is always one nucleus and one vacuole, but both
+may be more numerous. Reproduction takes place by division or by
+spore-formation. Fresh-water and marine.
+
+
+Amoeba guttala Duj.  Fig. 1.
+
+A minute form without pseudopodial processes, extremely hyaline in
+appearance, and characterized by rapid flowing in one direction.
+The body is club-shape and moves with the swollen end in advance.
+A comparatively small number of large granules are found in the
+swollen portion, while the smaller posterior end is quite hyaline.
+Contractile vacuole absent, and a nucleus was not seen.  Frequent in
+decomposing vegetable matter. Length 37µ. Traverses a distance of
+160µ in one minute.
+
+The fresh-water form of _A. guttula_ has a vacuole, otherwise
+Dujardin's description agrees perfectly with the Woods Hole forms.
+
+
+[Illustration: Fig. 1.--_Amoeba guttala_.]
+
+
+Amoeba?  Fig. 2.
+
+A more sluggish form than the preceding, distinguished by its larger
+size, its dense granulation, and by short, rounded pseudopodia,
+which, as in _Amoeba proteus_, may come from any part of the body.
+A delicate layer of ectoplasm surrounds the granular endoplasm, and
+pseudopodia formation is eruptive, beginning with the accumulation
+of ectoplasm. Movement rapid, usually in one direction, but may be
+backwards or sideways, etc. Contractile vacuole absent; the nucleus
+is spherical and contains many large chromatin granules. Length 80µ;
+diameter 56µ.
+
+
+[Illustration: Fig. 2.--_Amoeba_ sp.]
+
+
+Genus TRICHOSPHÆRIUM Schneider '78
+
+Synonym: _Pachymyxa hystrix_ Gruber.
+
+Marine rhizopods, globular or irregular in form, and slow to change
+shape. Dimorphic. Both forms multinucleate during vegetative life.
+Pseudopodia are long, thin, and thread-form, with rounded ends.
+Their function is neither food-getting nor locomotion, but probably
+tasting. The plasm of both forms is inclosed in a soft gelatinous
+membrane. In one form the jelly is impregnated with needles of
+magnesium carbonate (Schaudinn), but these are absent in the other
+form. The membrane is perforated by clearly defined and permanent
+holes for the exit of the pseudopodia. Reproduction occurs by
+division, by budding or by fragmentation, but the parts are
+invariably multinucleate. At the end of vegetative life the
+needle-bearing form fragments into numerous mononucleate parts; these
+develop into adults similar to the parent, but without the spines.
+At the end of its vegetative life this new individual fragments into
+biflagellated swarm-spores which may conjugate, reproducing the form
+with needles. Size up to 2 mm.
+
+
+Trichosphærium sieboldi Schneider.  Fig. 3.
+
+With the characters of the genus. A form which I have taken to be a
+young stage of this interesting rhizopod is described as follows:
+
+A minute, almost quiescent, form which changes its contour very
+slowly. The membrane is cap-like and extends over the dome-shaped
+body, fitting the latter closely. The  endoplasm is granular and
+contains foreign food-bodies. Nucleus single, spherical, and
+centrally located. Pseudopodia short and finger-form, emerging from
+the edge of the mantle-opening and swaying slowly from side to side
+or quiescent. The most characteristic feature is the presence of a
+broad, creeping sole, membranous in nature and hyaline in appearance.
+This membrane is the only evidence of ectoplasm, and it frequently
+shows folds and wrinkles, while its contour slowly changes with
+movements of body. The pseudopodia emerge from the body between this
+membrane and the shell margin. Contractile vacuole absent. Length
+42µ, width 35µ. In decomposing seaweeds, etc.
+
+Only one specimen of this interesting form was seen, and I hesitate
+somewhat in placing it on such a meager basis. It is so peculiar,
+however, that attention should be called to it in the hope of getting
+further light upon its structure and mode of life. Its membranous
+disk recalls the genus _Plakopus_; its mononucleate condition, its
+membranous disk, and the short, sometimes branched, pseudopodia
+make it difficult to identify with any phase in the life-history of
+_Trichosphærium_. I shall leave it here provisionally, with the hope
+that it may be found more abundantly another time.
+
+
+[Illustration: Fig. 3.--_Trichosphærium sieboldi_]
+
+
+Genus GROMIA Dujardin '35.
+
+(Dujardin 1835; M. Schultze '62; F. E. Schultze '74; Leidy '77;
+Bütschli '83; Gruber '84.)
+
+The form is ovoid or globular, and the body is covered by a tightly
+fitting, plastic, chitin shell, which, in turn, is covered by a fine
+layer of protoplasm. The flexibility of the shell makes the form
+variable as in the amoeboid types. The thickness of the shell is
+quite variable. The pseudopodial opening is single and terminal. The
+pseudopodia are very fine, reticulate, granular, and sharply pointed,
+and form a loose network outside of the shell opening. Nucleus single
+or multiple. Contractile vacuole is usually absent. Fresh and salt
+water.
+
+
+Gromia lagenoides Gruber '84.  Fig. 4.
+
+This species is not uncommon about Woods Hole, where it is found upon
+the branches of various types of algæ. The body is pyriform, with the
+shell opening at the larger end. The chitinous shell is hyaline and
+plastic to a slight extent, so that the body is capable of some
+change in shape. The shell is thin and turned inwards at the
+mouth-opening, forming a tube (seen in optical section in fig. 4)
+through which the protoplasm passes to the outside. The walls of this
+tube are thicker than the rest of the shell, and in optical section
+the effect is that of two hyaline bars extending into the body
+protoplasm. A thin layer of protoplasm surrounds the shell and
+fine, branching, pseudopodia are given off in every direction. The
+protoplasm becomes massed outside of the mouth-opening and from here
+a dense network of pseudopodia forms a trap for diatoms and smaller
+Protozoa. The nucleus is spherical and contains one or two large
+karyosomes. The protoplasm is densely and evenly granular, without
+regional differentiation. I have never observed an external layer of
+foreign particles, such as Gruber described in the original species.
+
+Length of shell 245µ; largest diameter 125µ.
+
+
+[Illustration: Fig. 4.--_Gromia lagenoides_.]
+
+
+Genus TRUNCATULINA D'Orbigny.
+
+A group of extremely variable foraminifera in which the shell is
+rotaline; i. e., involute on the lower side and revolute on the upper
+(Brady). The shell is calcareous and coarsely porous in older forms.
+The characters are very inconstant, and Brady gives up the attempt to
+distinguish the group by precise and constant characters.
+
+
+Truncatulina lobatula Walker & Jacob.
+
+Synonyms: See Brady '84 for a long list.
+
+"It is impossible to define by any precise characters the
+morphological range of the present species. Its variations are
+infinite." (Brady, p. 660.)
+
+This very common form, which occurs in all latitudes, was found
+frequently among the algæ at Woods Hole. Its characters are so
+difficult to define that for the present I shall limit my record to
+this brief notice. Size of shell 230µ by 270µ.
+
+
+Genus ACTINOPHRYS Ehr.
+
+
+The body is spherical and differentiated into granular endoplasm and
+vacuolated ectoplasm, but the zones are not definitely separated.
+There is one central nucleus and usually one contractile vacuole. The
+pseudopodia have axial filaments that can be traced to the periphery
+of the nucleus.  Fresh and salt water.
+
+Actinophrys sol Ehr., variety.  Fig. 5.
+
+Synonyms: See Schaudinn '95.
+
+The diameter is about 50µ; the vacuolated ectoplasm passes gradually
+into the granular endoplasm. This is the characterization given _A.
+sol_ by Schaudinn, and it applies perfectly to the freshwater forms.
+If I am correct, however, in placing an _Actinophrys_-like form
+found at Woods Hole in this species, the description will have to
+be somewhat modified. In this form (fig. 5) there is no distinction
+between ectoplasm and endoplasm, and there is an entire absence of
+vacuoles. The nucleus is central, and axial filaments were not seen.
+The single specimen that I found looked much like a Suctorian of
+the genus _Sphærophrya_, but the absence of a firm cuticle and the
+presence of food-taking pseudopodia with granule-streaming makes it a
+very questionable Suctorian, and 1 place it here until further study
+throws more light upon it.
+
+Diameter of body 40µ; length of pseudopodia 120 to 140µ.
+
+
+[Illustration: Fig. 5.--_Actinophrys sol_.]
+
+
+
+Genus HETEROPHRYS Archer.
+
+The body is globular with but slight differentiation into ectoplasm
+and endoplasm; one nucleus in the latter; contractile vacuoles
+one or many; pseudopodia on all sides, thin, and with peripheral
+granule-streaming; surrounded by a globular, rather thick coat of
+jelly, which is hyaline inside and granular on the periphery. Fresh
+and salt water.
+
+
+Heterophrys myriapoda Archer.  Fig. 6.
+
+Synonym: _H. marina_ Hert. & Less. '74.
+
+Diameter 25 to 80µ; pseudopodia twice as long as the body diameter;
+the plasm often contains chlorophyll bodies (Zoochlorella). The
+granular part of the gelatinous layer is thick (up to 10µ). The
+spine-like processes are very thin and short. (Schaudinn '95.) The
+marine form found at Woods Hole probably belongs to this species,
+as described by Schaudinn. The short pseudopodia which give to
+the periphery a fringed appearance are quite regularly placed in
+connection with the pseudopodia. The latter are not so long as twice
+the body diameter, the longest being not more than equal to the
+diameter of the sphere. The body inside of the gelatinous covering
+is thickly coated with bright yellow cells similar to those
+on Radiolaria. The animal moves slowly along with a rolling
+motion similar to that described by Pènard '90, in the case of
+_Acanthocystis_. Diameter of entire globe 35µ; of the body without
+the jelly 18µ. The extremely fine granular pseudopodia are 8 to 35µ
+long. Common among algæ.
+
+This form was probably meant by Peck '95, when be figured "a
+heliozoön."
+
+
+[Illustration: Fig. 6.--_Heterophrys myriapoda_.]
+
+
+KEY TO ORDERS OF FLAGELLIDIA.
+
+Small, body usually amoeboid; 1 or more   Order MONADIDA.
+flagella; no mouth
+
+Small; plasmic collar around the          Order CHOANOFLAGELLIDA.
+flagellum
+
+With 2 or more flagella; one trails       Order HETEROMASTIGIDA.
+behind
+
+With 3 or more flagella, none of which    Order POLYMASTIGIDA.
+trails
+
+Large; firm body wall; 1 or 2 flagella;   Order EUGLENIDA.
+mouth or pharynx, or both
+
+Medium size; with chlorophyll,            Order PHYTOFLAGELLIDA.
+no mouth, usually colonial
+
+Small; silicious skeleton; parasitic      Order SILICOFLAGELLIDA.
+on Radiolaria or free                     (One genus,
+                                          _Distephanus_ Stöhr)
+
+
+KEY TO THE FAMILIES OF MONADIDA.
+
+No mouth; 1 or 2 flagella: amoeboid       Family _Rhizomastigidæ_
+with lobose or ray-like pseudopodia
+
+Mouth at base of single flagellum;        Family _Cercomonadidæ_
+plastic; no pseudopodia
+
+One flagellum; inclosed in gelatinous     Family _Codonoecidæ_
+or membranous cups
+
+One flagellum; tentacle like process      Family _Bikoecidæ_
+at base of flagellum; inclosed in cup
+
+One main flagellum and 1 or 2             Family _Heteromonadidæ_
+accessory flagella
+
+
+KEY TO MARINE GENERA OF MONADIDA.*
+
+Family _Rhizomastigidæ_:
+
+   1. Flagellum repeatedly thrown off     Genus *_Mastigamoeba_
+      and reassumed                       in part
+
+   2. Flagellum never thrown off          3
+
+   3. a. Pseudopodia lobose               Genus _Mastigamoeba_
+
+      b. Pseudopodia ray-like             Genus _Mastigophrys_
+
+Family _Codonoecidæ_:
+
+   1. Goblet-shaped cups adherent         Genus *_Codonoeca_
+      by stalk
+
+Family _Heteromonadidæ_:
+
+   1. The long flagellum vibratory        Genus *_Monas_
+
+   2. The long flagellum rigid;           Genus _Sterromonas_
+      shorter one vibrates
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE QENERA OF CHOANOFLAGELLIDA.
+
+   1. Without gelatinous                  3
+      or membranous test
+
+   2. With gelatinous                     4
+   or membranous test
+
+   3. a. Attached forms:
+
+         1. Without a stalk, or with      Genus *_Monosiga_
+            a very short one
+
+         2. With a long, simple, stalk    Genus *_Codonosiga_
+
+         3. With a long, branched, stalk  Genus _Codonocladium_
+
+      b. Free-swimming                    Genus _Desmarella_
+
+   4. Colonial, and with a gelatinous     Genus _Proterospongia_
+      covering
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO FAMILIES AND MARINE GENERA OF HETEROMASTIGIDA.
+
+   1. Two flagella nearly equal in size   Family _Bodonidæ_
+
+      One main and 2 accessory flagella   Family _Trimastigidæ_
+
+Family _Bodonidæ_:
+
+   1. Body very plastic,                  Genus *_Bodo_
+      almost amoeboid
+
+      Body not plastic; with large        Genus *_Oxyrrhis_
+      anterior cavity, holding flagella
+
+Family _Trimastigidæ_:
+
+   1. With an undulatory membrane         Genus _Trimastix_
+      between accessory flagella
+
+      Without such membrane; flagella     Genus _Costia_
+      contained in a ventral groove
+      while at rest
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF POLYMASTIGIDA.
+
+   1. Body flattened; ends rounded;       Genus _Trepomonas_
+      sides hollowed; often with
+      wing-like processes; cross
+      section S-shaped
+
+   2. Body pyriform; one large            Genus _Tetramitus_
+      asymmetrical groove; 4 flagella
+
+   3. Body spherical; many flagella       Genus _Multicilia_
+      equally distributed
+
+
+KEY TO FAMILIES AND MARINE GENERA OF EUGLENIDA.
+
+   1. With deeply-insunk pharynx;         2
+      no mouth
+
+      With pharynx and distinct mouth     Family _Peranemidæ_
+
+   2. Body plastic; usually with          Family _Euglenidæ_
+      chromatophores and eye-spot
+
+      Body plastic; no chromatophores;    Family _Astastidæ_
+      no eye-spot
+
+Family _Euglenidæ_:
+
+      Body _Euglena_-like, inclosed       Genus _Trachelomonas_
+      in shell with round opening for
+      exit of flagellum
+
+Family _Astastidæ_:
+
+      Body with one flagellum             Genus *_Astasia_
+
+Family _Peranemidæ_:
+
+   1. Body striped; plastic;              Genus _Heteronema_
+      two diverse flagella
+
+   2. Body striped; not plastic;          Genus *_Anisonema_
+      posterior flagellum longer
+      than the other
+
+   3. Body striped; not plastic;          Genus _Entosiphon_
+      with rod-like organ in pharynx
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus MASTIGAMOEBA F. E. Schultze '75.
+
+(Kent '81; Bütschli '86; Klebs '92; Senn 1900.)
+
+In general the form is oval and either regular in outline or
+irregular through the presence of many pseudopodia. One flagellum
+usually quite large and distinct. Differentiation of ectoplasm and
+endoplasm distinct or wanting. One to several contractile vacuoles.
+The pseudopodia are occasionally withdrawn, and the flagellum is the
+sole means of locomotion. In some cases the flagellum turns into a
+pseudopodium, and, conversely, the pseudopodium at one end may become
+a flagellum (see below). In some rare cases the ectoplasm secretes a
+gelatinous mantle. Reproduction not observed.
+
+Fresh and salt water.
+
+
+Mastigamoeba simplex, n. sp.  Fig. 7.
+
+A very small form, first seen in the flagellated stage, aroused my
+interest by reason of the fact that its flagellum lost its regular
+outline and became amoeboid, turning to a pseudopodium, while at the
+same time other pseudopodia were protruded from different parts of
+the periphery. In this condition ectoplasm and endoplasm could be
+made out with the clearest definition. After the pseudopodia were
+well formed, the body became flat and closely attached to the glass
+slide. In a short time one of the pseudopodia became longer than the
+rest; the body became more swollen; the pseudopodia were gradually
+drawn in, with the exception of the more elongate one; this became
+active in movement and finer in diameter, until ultimately it formed
+a single flagellum at the anterior of a small monadiform flagellate.
+The process was repeated two or three times under my observation,
+so that I am convinced that it was not a developmental form of
+some rhizopod. Several of them were seen at different times during
+the summer, and they were always of the same size and form in
+the flagellated or amoeboid condition. I did not make out their
+reproduction, and I shall not be satisfied that this is a good
+species until their life history is known.
+
+In decaying algæ. Length 10µ.
+
+
+[Illustration: Fig. 7.--_Mastigamoeba simplex_.]
+
+
+Genus CODONOECA James Clark '66.
+
+(Kent '81.)
+
+Small forms inclosed in cup or "house" of ovoid or goblet shape,
+colorless and probably gelatinous (chitin?) in texture, and borne
+upon a stalk. The monad does not completely fill the test.
+Contractile vacuole single, posterior.
+
+
+Codonoeca gracilis, n. sp.  Fig. 8.
+
+The cup is urn-shaped with a well-defined neck or collar borne upon a
+shoulder-like end of the body. It is hyaline, colorless, and carried
+upon a stalk equal in length to the cup or shorter than this. The
+animal does not fill the cup, nor is it attached by a filament to
+the latter. There is a single flagellum. The nucleus is minute and
+lateral in position; the contractile vacuole is in the posterior end
+of the body. Total length of cup and stalk 21µ; of cup alone 12µ.
+This minute form looked so much like a choanoflagellate that I
+supposed it to be one until I discovered an empty case (Fig. 8).
+
+
+[Illustration: Fig. 8.--_Codonoecea gracilis_.]
+
+
+
+Genus MONAS (Ehr.) Stein '78
+
+(Kent '81; Bütschli '86; Klebs '97; Senn 1900.)
+
+The body is small, globular or oval and either free-swimming or
+fastened by one of the two flagella. The body is sometimes a little
+amoeboid, with short pseudopodial processes. In addition to the main
+flagellum, there are usually one or two small flagella at the basis
+of the larger one.  The nucleus is usually anterior, and one or two
+contractile vacuoles are present.
+
+
+Monas sp.  Fig. 9.
+
+An extremely small form (3µ) attached by a thread of
+protoplasm--perhaps a flagellum, to algæ. The body is ovoid and
+the main flagellum is about four times the length of the body. The
+contractile vacuole is posterior. Only one specimen was seen and
+upon this I shall not attempt to name the species.
+
+
+[Illustration: Fig. 9.--_Monas_ sp.]
+
+
+Genus MONOSIGA Kent '81.
+
+(Bütschli '86; Francé '97; Senn 1900.)
+
+Small colorless forms of Choanoflagellida, always naked and solitary.
+The posterior end is attached directly to the substratum, or
+there is a short stalk not exceeding the body in length. Kent '81
+distinguished nine species, but Bütschli questioned the accuracy
+of many of these, and in this he was followed by Francé '97, who
+recognized three species--_Monosiga ovata_, _M. fusiformis_, and _M.
+augustata_. Fresh and salt water.
+
+
+Monosiga ovata S. Kent '81.  Fig. 10.
+
+Synonyms: _M. brevipes_ S. K.; _M. consociata_ S. K.; _M. limnobia_
+Stokes.
+
+The individuals are unstalked or provided with a very short stalk
+less than the body in length. The form is spherical or ovate,
+broadest at the base and tapering to the extremity. The collar is
+somewhat variable in size. In the Woods Hole forms it was about
+the length of the body. Oil particles present. Contractile vacuole
+posterior, nucleus anterior.
+
+Fresh and salt water. Length of body without the collar 5µ.
+
+
+[Illustration: Fig.10.--_Monosiga ovata_.]
+
+
+Monosiga fusiformis S. K.  Fig. 11.
+
+Synonyms: _M. steinii_ S. K.; _M. longicollis_ S. K.
+
+The individuals are unstalked, minute, and of a general flask-shape.
+The body is swollen centrally and tapers slightly at each end. There
+is no stalk, the body being fixed by the attenuate posterior end.
+There are two contractile vacuoles and one nucleus, which is situated
+a little above the body center. Fresh and salt water. Length without
+collar 9µ; length of collar 3µ.
+
+
+[Illustration: Fig. 11.--_M. fusiformis_.]
+
+
+Genus CODONOSIGA (Jas. Clark '67).
+
+(Bütschli '78; Kent '81; Francé '97; Senn 1900.)
+
+This genus, as modified by Francé, is distinguished from the
+preceding by the possession of an unbranched stalk much longer than
+the body length. The body is naked and of various shapes, and the
+individuals are solitary or colonial upon a single stalk. Kent '81
+enumerates no less than 10 species, which were cut down by Bütschli
+to 1. Francé admits 4--_C. botrytis_ Jas. Clark; _C. grossularia_;
+_C. pyriformis_, and _C. furcata_, all S. Kent--but regards the
+second and third as merely form varieties of the first.
+
+
+Codonosiga botrytis (Ehr. sp.) Jas. Clark '67.  Fig. 12.
+
+Francé gives the following synonyms: _Epistylia botrytis_ Ehr.;
+_E. digitalis_ Stein, _Zoothamnium parasitica_ Stein; _Anthophysa
+solitaria_ Fresenius; _Codonosiga pulcherrima_ Jas. Clark; _Monosiga
+gracilis_ S. Kent; _M. globulosa_ S. Kent; _Codonosiga pyriformis_
+Kent; _C. grossularia_ Kent; (Francé).
+
+The individuals are small and provided with a long unbranched, or
+terminal, simply split stalk. The individuals are single or colonial.
+The Woods Hole form measured 22µ over all; the body was 5µ, the
+collar 3µ, and the stalk 14µ. No colonies were seen, and only a few
+individuals upon red algæ.
+
+
+[Illustration: Fig. 12.--_Codonosiga botrytis_.]
+
+
+Genus BODO (Ehr.) Stein.
+
+(Stein '59, Bütschli '83; Klebs '92; Senn 1900.)
+
+The body is naked, usually amoeboid in its changes, and provided with
+two flagella, one of which is usually trailed along under and behind
+the animal. The anterior end is usually pointed, with the flagella
+arising from a minute depression; the posterior end is rounded.
+Specific characters very difficult to analyze. Fresh and salt water.
+
+
+Bodo globosus Stein.  Fig. 13.
+
+The body during movement is globular or ovoid, without any anterior
+process. The trailing flagellum is invariably much longer than the
+vibratory one. The contractile vacuole lies in the anterior half of
+the body. Solid food particles are taken in near base of flagella.
+
+Length of body 9 to 12µ; diameter 8 to 11µ. Common.
+
+
+[Illustration: Fig. 13.--_Bodo globosus_.]
+
+
+Bodo caudatus (Duj.) Stein.  Fig. 14.
+
+Synonyms: _Amphimonas caudatus_ Duj.; _Diptomastix caudata_ Kent.
+
+The body is variable in shape, but usually flattened and pointed
+posteriorly. An anterior process is almost always present, and
+below this the flagella are inserted in a minute depression. The
+contractile vacuole is close to the base of the flagella. The
+flagella are about the same size, the anterior one usually somewhat
+longer. Common. Length 12 to 18µ.
+
+This species was seen by Peck '95 and described as a small
+flagellate.
+
+
+[Illustration: Fig. 14.--_Bodo caudatus_.]
+
+
+Genus OXYRRHIS Duj.
+
+(Kent '81; Bütschli '86; Klebs '92; Senn 1900.)
+
+Medium-sized forms, somewhat oval in shape, with a rounded posterior
+end. The anterior end is continued dorsally in a somewhat attenuate
+pointed process. At the base of this process is a large cavity or
+funnel, on the dorsal wall of which, or on a projection from this
+wall, are two equal-size flagella. When at rest, the flagella are
+directed backwards. The nucleus is central. In moving, the posterior
+end is invariably in advance. This genus is exceptional among
+Mastigophora in that division is transverse instead of longitudinal.
+
+
+Oxyrrhis marina Duj.  Fig. 15.
+
+With the characters of the genus. Contractile vacuole not seen.
+Length 28 to 40µ.
+
+
+[Illustration: Fig. 15.--_Oxyrrhis marina_.]
+
+
+Genus ASTASIA Ehr.
+
+Flagellates with one flagellum, a spindle-form body and a high
+degree of plasticity, the contour constantly changing. A distinct,
+usually striped cuticle is invariably present. "Eye-spots" are
+absent. Fresh and salt water.
+
+
+Astasia contorta Duj.  Fig. 16.
+
+_Astasia inflata_ Duj. '41.
+
+The body is colorless, transparent, and flexible. It is largest in
+the center, thence tapering at the two extremities. The surface of
+the cuticle is obliquely striated, giving to the animal a distinctly
+twisted appearance. The contractile vacuole is in the anterior
+neck-like portion of the body. The flagellum is inserted in a
+distinct oesophageal tube, into which the contractile vacuole
+empties. This tube is continued into a deeper pharyngeal apparatus of
+unknown function.
+
+Common in decaying algæ. Length 60µ; greatest diameter 30µ.
+
+
+[Illustration: Fig. 16.--Two aspects of _Astasia contorta_.]
+
+
+Genus ANISONEMA Bütschli
+
+Flagellates with two flagella, of which one is directed forwards and
+is concerned with the locomotion of the animal, while the other is
+directed backwards and drags after the animal when in motion. Body
+slightly compressed dorso-ventrally (fig. 17, section). An oral
+furrow is present on the ventral side and the two flagella originate
+in it (fig. 17, at left). The vacuole is on the left side. Food
+vacuoles are present in the posterior part. The nucleus is central.
+Movement creeping.
+
+Fresh and salt water.
+
+
+Anisonema vitrea (Duj.)  Fig. 17.
+
+Synonyms: _Tropidoscyphus octocostatus_ Stein '83; _Sphenomonas_ Kent
+'81; _Ploeotia vitrea_ Senn 1900.
+
+With the characteristics of the genus. It differs from freshwater
+forms in having eight furrowed surfaces running somewhat spirally
+from the posterior to the oral end. Length 50µ; width 23µ.  This
+attractive flagellate was quite common in decaying algæ at Woods
+Hole; its shaking movement, its peculiar furrowed surfaces, and,
+above all, its perfectly transparent, vitreous appearance, were well
+described by Dujardin. Stein's _Tropidoscyphus octocostatus_ is a
+fresh-water form which may possibly be a distinct species, especially
+as it is described with both flagella directed forwards.
+
+
+[Illustration: Fig. 17.--_Anisonema vitrea_.]
+
+
+Genus DISTEPHANUS  Stöhr.
+
+An aberrant flagellate bearing a single flagellum and a silicious
+skeleton resembling those of the Radiolaria. The skeleton consists
+of two rings of different diameter parallel with one another and
+connected by silicious bars. From the wider ring half a dozen bars
+radiate outwards and a similar number of short thorn-like bars point
+inwards obliquely. The color is yellow, and except for the flagellum
+the form might easily be mistaken for a Radiolarian, as has been the
+case repeatedly.
+
+
+Distephanus speculum Stöhr.
+
+_Dictyocha speculum_ Stöhr; _Dictyocha_ Auc.
+
+With the characters of the genus.
+
+A single specimen only of this very interesting form was seen at
+Woods Hole. It occurred in a collection of tow made near the end of
+the wharf during the evening.
+
+
+KEY TO FAMILIES OF DINOFLAGELLIDIA.
+
+   1. No crossfurrow; two free flagella   Family _Prorocentridæ_
+
+   2. One or more cross-furrows           3
+
+   3. Cross-furrow nearly central         Family _Peridinidæ_
+      (cf. _Oxytoxum_)
+
+      Cross-furrow close to               Family _Dinophysidæ_
+      anterior end
+
+      Several cross-furrows               Family _Polydinidæ_
+      and flagella                        (One genus, _Polykrikos_.)
+
+
+KEY TO MARINE GENERA OF PROROCENTRIDÆ.
+
+Diagnostic characters: The transverse furrow is absent and the two
+flagella arise from the anterior end of the body. The shell may be
+bivalved.
+
+   1. No tooth-like process dorsal        Genus *_Exuviælla_
+      to the flagellum
+
+   2. With tooth-like process dorsal      Genus _Prorocentrum_
+      to the flagellum
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF PERIDINIDÆ.
+
+Diagnostic characters: The cross-furrow is nearly central (see,
+however, _Oxytoxum_); the body may or may not have a shell; the
+shell may or may not be composed of distinct plates; the plates are
+distinguished as _equatorial_ (_i.e._, bordering the cross-furrow),
+_apical_, and _antapical_, while still another, the "rhombic plate",
+may be present, extending from the cross-furrow to the apex.
+
+   1. Without distinct shell              Genus *_Gymnodinium_
+
+      With a distinct shell               2
+
+   2. Shell not composed of definite      3
+      plates
+
+      Shell composed of definite plates   4
+
+   3. Cross-furrow replaced by            Genus _Ptychodiscus_
+      thin-skinned band
+
+      Cross-furrow well defined;          Genus _Protoceratium_
+      reticulate markings raised
+      on shell-surface
+
+      Cross-furrow well defined;          Genus *_Glenodinium_
+      no markings
+
+   4. Two parts of shell equal or         5
+      nearly equal
+
+      Two parts of shell very unequal     11
+
+   5. With transverse flagellum in        6
+      a distinct furrow
+
+      Transverse flagellum not in a       10
+      furrow
+
+   6. With horns, or with wing-like       7
+      processes
+
+      Without processes of any kind       9
+
+   7. Processes small, wing-like,         Genus _Diplopsalis_
+      around flagellum-fissure
+
+      Processes horn-like                 8
+
+   8. Anterior part with 7 equatorial     Genus *_Peridinium_
+      and 1 rhombic plates
+
+      Anterior part with 5 equatorial     Genus _Gonyaulax_
+      and no rhombic plates
+
+      Anterior part with 3 equatorial     Genus *_Ceratium_
+      and no rhombic plates
+
+   9. Anterior part with 14 equatorial    Genus _Pyrophacus_
+      and 1 rhombic plates
+
+      Anterior part with 7 equatorial     Genus _Goniodoma_
+      plates
+
+      Anterior part with 4 equatorial     Genus _Amphidoma_
+      plates
+
+  10. Apical extremity drawn out          Genus _Podolampas_
+      into a tube
+
+      Apical extremity not drawn out      Genus _Blepharocysta_
+      into a tube
+
+  11. Cross-furrow deep, with great       Genus _Ceratocorys_
+      ledge-like walls
+
+
+      Cross-furrow wide, no ledge-like    Genus _Oxytoxum_
+      walls
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF DINOPHYSIDÆ.
+
+Diagnostic characters: The cross-furrow is above the center of the
+body, and its edges, as well as the left edge of the longitudinal
+furrow, are usually produced into characteristic ledges; those of
+the cross-furrow usually form great funnel-like anterior processes,
+while those of the longitudinal furrow usually form great, lateral,
+wing-like processes ornamented by ribs and other markings.
+
+   1. Without shell; longitudinal         Genus *_Amphidinium_
+      furrow may open & close
+
+   2. With shell; longitudinal furrow     3
+      unchangeable
+
+   3. With distinct apical funnel         4
+
+      No apical funnel                    Genus _Phalacroma_
+
+   4. With great wing-like ledge          5
+
+      Ledges very small; body long,       Genus _Amphisolenia_
+      needle-like
+
+   5. Ledge of longitudinal furrow        6
+      extends to posterior end
+
+      Ledge of longitudinal furrow        Genus _Dinophysis_
+      does not extend to posterior end
+      (Recorded by Peck ('93-'95) as very abundant at Woods Hole
+      and in Buzzards Bay.)
+
+   6. Ledge is continued dorsally to      Genus _Ornithocercus_
+      the cross-furrow
+
+      Ledge is not continued dorsally     7
+
+   7. With deep dorsal cavity;            Genus _Citharistes_
+      secondary funnel not notched
+
+      No dorsal cavity; secondary         Genus _Histioneis_
+      funnel deeply notched
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EXUVIÆLLA Cienkowsky '82.
+
+(Klebs '81; Pouchet '83, '86.)
+
+The form varies from globular to ovoid, with occasionally a sharp
+posterior end. Shells are usually somewhat compressed, and consist
+of two valves, which frequently slide one over the other in such a
+manner as to show the structure with great clearness. The right shell
+may have a distinct indentation in the anterior edge. There are two
+lateral, discoid, brown chromatophores, each of which possesses a
+central amylum granule. The nucleus is posterior. Salt water.
+
+
+Exuviælla lima Ehr.  Fig. 18.
+
+Synonyms _Pyxidicula_ Ehr.; _Cryptomonas_ Ehr.; _Prorocentrum lima_
+Kent; _Amphidinium_ Pouchet.
+
+The shell is ovate, rounded and swollen posteriorly. The anterior
+border of both shells is slightly indented. The shell is quite thick.
+The animal moves through the water very slowly. Dark brown in color.
+Length 48µ; width 44µ.
+
+
+[Illustration: Fig. 18.--_Exuviælla lima_.]
+
+
+Exuviaella marina Cienkowsky.  Fig. 19.
+
+A smaller form than the preceding, more elliptical in outline, with
+a thinner shell and with large granules throughout the endoplasm.
+The nucleus is spherical and subcentral in position and possesses a
+distinct central granule. This may be a small variety of _E. lima_.
+
+
+[Illustration: Fig. 19.--_Exuviælla marina_.]
+
+
+Genus GYMNODINIUM Stein '78.
+
+(Bergh '81; Kent '81; Pouchet '83, '85; Entz '84; Schütt '95.)
+
+The general structure of these forms is similar to that of
+_Glenodinium_; the most striking and positive difference is the
+absence of a shell. The animals are, as a rule, spherical, yet they
+may be pointed at the two ends or at one of them. They are also
+frequently flattened dorso-ventrally. The transverse furrow may
+be either circular and straight around the body or may describe a
+spiral course, passing even twice around the body. The flagella
+arise near cross-furrow or, in some cases, in longitudinal furrow.
+Chromatophores may or may not be present and food-taking is holozoic,
+in many cases at least. In some cases ectoplasm and endoplasm can be
+distinguished. Fresh and salt water.
+
+
+Gymnodinium gracile Bergh '82, var. sphærica, n.  Fig. 20.
+
+The body is divided by the transverse furrow into a shorter anterior
+and a longer posterior part. The longitudinal furrow is broader at
+the posterior extremity than at the cross-furrow. The structural
+feature upon which this new variety is made is the unvarying
+plumpness of the body, making it almost spherical, except for
+a slight flattening dorso-ventrally. The nucleus is large and
+ellipsoidal, with characteristic longitudinal markings of chromatin.
+The endoplasm is evenly granular, with a number of large ingested
+food bodies. The color is brown, not rose-red as in Bergh's species,
+nor is the Woods Hole form as large as the latter. Length of body
+68µ; width 55µ. Common.
+
+
+[Illustration: Fig. 20.--_Gymnodinium gracile_, var. _sphærica_.]
+
+
+Genus GLENODINIUM (Ehr.), Stein '83.
+
+(Bergh '82; Bütschli '86; Pouchet '85; Daday '86.)
+
+Small globular forms with two distinct furrows, one transverse around
+the body, the other longitudinal upon the face only. The shell is
+soft and structureless with a distinct aperture near the meeting
+point of the two furrows. The endoplasm usually, but not always,
+contains a bright red eye-spot.
+
+Fresh and salt water.
+
+
+Glenodinium compressa, n. sp.  Fig. 21, a, b, c.
+
+This species resembles _G. acuminata_ of Ehrenberg except that it is
+strongly compressed laterally. The longitudinal furrow extends nearly
+to the extremity of the animal. It begins as a narrow slit and widens
+as it progresses upon the left side; it also becomes much deeper
+on this side and at the bottom of the depression the longitudinal
+flagellum is inserted. The transverse furrow runs evenly around the
+body near the upper pole, giving to the shell almost the aspect of
+an _Amphidinium_. Brown chromatophores may or may not be arranged
+radially about a central amylum granule. One striking characteristic
+is the depth of the two furrows. The nucleus is elongate and somewhat
+curved; it lies against the posterior wall of the rather thick shell.
+Not uncommon.
+
+Length 40µ; breadth 32µ; width 18µ.
+
+The posterior end of the animal is often somewhat pointed and this
+point frequently becomes attached, so that the animal whirls around
+upon it as upon a pivot.
+
+
+[Illustration: Fig. 21 a, b, c.--_Glenodinium compressa_, n. sp.]
+
+
+Glenodinium cinctum Ehr.  Fig. 22.
+
+The body is globular, smooth, and homogeneous.  Brown chromatophores
+arranged radially, each in the form of a cone, the base of which
+rests against the shell while the points turn inward.  A bright-red
+eye-spot may or may not be present; when present it is placed near
+the junction of the two furrows. The longitudinal furrow is small.
+Fresh water and salt.
+
+Length and diameter the same, 21µ.
+
+This species was observed by Peck '93.
+
+
+[Illustration: Fig. 22.--_Glenodinium cinctum_.]
+
+
+Genus PERIDINIUM Ehr. '32, Stein '83.
+
+(Claparède & Lachmann '58; Bergh '81; Pouchet '83; '85; Gourret '88;
+Bütschli '86.)
+
+The form is globular, ovoid or elongate, the apex frequently drawn
+out into a long tube. The transverse and longitudinal furrows are
+quite distinct, the former having often a spiral course about the
+body. The two halves of the body are similar, the posterior being
+somewhat shorter; the anterior half has seven equatorial plates, an
+oral plate, two lateral apical plates, and one or two dorsal plates.
+The two antapical plates frequently have a tooth-like process. The
+bodies are colorless, green or brown.
+
+Fresh and salt water.
+
+
+Peridinium digitale Pouchet.  Fig. 23.
+
+Synonyms: _Protoperidinium digitale_ Pouchet; _Protoperidinium_ Bergh
+p. p.; _P. divergens_ Peck.
+
+The shell is covered with pits of large size. The posterior part
+is hemispherical and surmounted by a single horn or spine. The
+transverse furrow is very oblique, and its two extremities are united
+by a sigmoid longitudinal furrow. The anterior half bears two spines
+or horns of different size, and variable.  The nucleus is spherical
+or ellipsoidal and placed in the posterior half of the shell.
+
+Length 68µ; diameter 54µ. Common.
+
+Although the description of Pouchet's _P. digitale_ differs in some
+respects from a careful description of the Woods Hole form, I think
+the species are the same. The chief difference is in the single horn
+of the posterior half; in Pouchet's form this is furrowed by a narrow
+groove which runs to the S-shaped longitudinal furrow. In the Woods
+Hole form I was unable to make out such a furrow. The flagella, also,
+were not seen. This same form was pictured by Peck '95 as _P.
+divergens_.
+
+
+[Illustration: Fig. 23.--_Peridinium digitale_.]
+
+
+Peridinium divergens Ehr.  Fig. 24.
+
+Synonym: _Ceratium divergens_ Kent.
+
+The shell is spheroidal, widest centrally, attenuate and pointed
+posteriorly; the anterior portion is armed with two short, pointed
+horns, each of them having a toothed process at the basal portion
+of the inner margin. They are frequently colorless and beautifully
+transparent, the body being free from large opaque granules; again
+they are colored brown or yellow. The nucleus is large and elongate
+and finely granular. 75µ long and 68µ in diameter. Common.
+
+
+[Illustration: Fig. 24.--Ventral and dorsal aspects of _Peridinium
+divergens_.]
+
+
+Genus CERATIUM (Schrank).
+
+(Stein '78; Perty '52; Clap & Lach. '58; Bergh '82; Pouchet '83;
+Gourret & Roeser '88; Bütschli '85; Kent '81; Senn 1900; Schütt '98.)
+
+The general shape is a flattened sphere with three long processes
+or horns. The cross-furrow is either spiral or circular; the
+longitudinal furrow is usually wide and occupies the greater part of
+the anterior half of the shell. The shell is thick, reticulate or
+striped, and sometimes provided with short spines; often distinctly
+porous. The anterior half is composed of 3 equatorial and 3 apical
+plates, the latter being continued into the horn-like process. The
+posterior half is composed of 3 equatorial and one apical plate
+continued into the posterior horn. The right posterior plate is
+continued into a similar horn which may remain rudimentary or be
+continued into a considerable process. Similarly the left posterior
+horn is usually developed, but remains small. There may be from 2 to
+3, 4, and 5 horns. Chromatophores usually present, green to yellow
+brown.
+
+Fresh and salt water.
+
+
+Ceratium tripos Ehr.  Fig. 25.
+
+The body is somewhat triangular and bears three horns, two of which
+are shorter than the other one and slightly curved upward.
+
+Length, including the horns, 290µ.
+
+
+[Illustration: Fig. 25.--_Ceratium tripos_.]
+
+
+Ceratium fusus Ehr.  Fig. 26.
+
+Synonym: _Peridinium fusus_ Ehr.
+
+The animal is very elongate, due to the presence of two long horns
+at the extremities of the body. Color, yellow with chromatophores.
+Length 285µ; width 23µ.
+
+Both of these species are common in the tow and in the algæ at the
+edge of the wharf. Both of them are mentioned by Peck in '93 and '95.
+
+
+[Illustration: Fig. 26.--_Ceratium fusus_.]
+
+
+Genus AMPHIDINIUM Clap. & Lach.
+
+The body is ovoid to globular and usually much flattened
+dorso-ventrally. The anterior portion is very much reduced and is
+somewhat head-like or cap-like. The longitudinal furrow extends
+through the entire posterior body length and is apparently capable
+of widening and narrowing. It is probably naked (see here Klebs,
+Pouchet, Bütschli), although Stein maintained that there is a
+delicate cuticle-like shell. Chromatophores of brown or green colors
+present and usually grouped radially about a central amylum granule.
+The nucleus is posterior.
+
+Fresh and salt water.
+
+
+Amphidinium operculatum Clap. & Lach.  Fig. 27.
+
+The body is oval and flattened. The transverse furrow is at the
+extremity (posterior) of the body and the small portion, which is
+thus apparently cut off, is the cap-like or operculum-like structure
+which gives the name to the species. Klebs maintains that the two
+furrows are not connected, but in this he is certainly mistaken,
+provided we have the same species under consideration.  Very common
+about Woods Hole.
+
+Length from 40 to 50µ; width 30µ; thickness 15µ.
+
+
+[Illustration: Fig. 27.--_Amphidinium operculatum_.]
+
+
+
+KEY TO INFUSORIA.
+
+1. With cilia                             Subclass _Ciliata_. 3
+
+2. Without cilia (in adult state)         Subclass _Suctoria_
+   tentacles
+
+3. a. Without a specialized fringe of     Order _Holotrichida_
+      large cilia (ad. zone)
+
+   b. With general covering of cilia      Order _Heterotrichida_
+      + adoral zone
+
+   c. With cilia on ventral side          Order _Hypotrichida_
+      + adoral zone
+
+   d. With cilia in region of adoral      Order _Peritrichida_
+      zone, and about mouth only
+
+
+KEY TO FAMILIES OF THE HOLOTRICHIDA.
+
+A. Mouth closed except during food        1
+   ingestion; no undulating membrane
+
+   Mouth always open; with undulating     2
+   membrane
+
+   1. _Gymnostomina_.
+
+      a. Mouth terminal or subterminal.   Family _Enchelinidæ_
+         Food is swallowed and not
+         introduced by currents
+
+      b. Mouth terminal or subterminal;   Family _Trachelinidæ_
+         body frequently drawn out into
+         long process; mouth may have
+         specialized framework.
+
+      c. Mouth central or posterior;      Family _Chlamydodontidæ_
+         pharynx with supporting
+         framework
+
+   2. _Trichostomina_.
+
+      a. Mouth anterior or central;       Family _Chiliferidæ_
+         pharynx short or absent;
+         peristomial depression faint
+         or absent
+
+      b. Mouth central; pharynx long,     Family _Urocentridæ_
+         tubular; cilia in two broad
+         zones
+
+      c. Mouth posterior; form            Family _Microthoracidæ_
+         asymmetrical; cilia dispersed
+         or limited to oral region
+
+      d. Mouth anterior or central.       _Paramoecidæ_
+         Peristomial depression           (One genus, _Paramoecium_)
+         clearly marked.
+
+      e. Mouth at end of long peristome   Family _Pleuronemidæ_
+         running along ventral side;
+         body dorso-ventrally or
+         laterally compressed; left edge
+         of peristome with great, sail-
+         like undulating membrane
+
+      f. Mouth and pharynx distinct,      Family _Isotrichidæ_
+         posterior; cilia uniform.
+         Parasites in ruminants.
+
+      g. Mouth absent; body vermiform,    Family _Opalinidæ_
+         cilia uniform. Usually
+         parasites.
+
+
+KEY TO MARINE GENERA OF ENCHELINIDÆ
+
+Diagnostic characters: Form ellipsoid or ovoid; the mouth is
+invariably terminal and is usually round--more rarely slit-formed; it
+is closed except when food is taken. An oesophagus when present is a
+short, invariably non-ciliated tube which is usually surrounded by
+a more or less clearly defined buccal armature. The anus is usually
+terminal. Large food particles are swallowed, never introduced by
+currents.
+
+   1. Body naked                          3
+
+   2. Body inclosed in a shell or coat    7
+
+   3. a. Cilia uniform about the entire   4
+         body; body symmetrical
+
+      b. Cilia in the mouth region        5
+         longer than the others; body
+         symmetrical
+
+      c. Bristles, or tentacles, in       6
+         addition to cilia
+
+   4. Mouth terminal; body ellipsoidal    Genus _Holophrya_
+      to ovoid
+
+   5. a. Mouth terminal; body elongate,   Genus _Chænia_
+         flexible, and elastic
+
+      b. Mouth terminal; "neck" highly    Genus *_Lacrymaria_
+         elastic; entire body
+         flexible; conical "head"
+
+      c. Mouth terminal; "neck" highly    Genus *_Trachelocerca_
+         elastic; entire body
+         flexible; "head" square
+
+      d. Mouth terminal; "neck" highly    Genus _Lagynus_
+         elastic; no separate
+         mouth-bearing portion
+
+   6. a. Body asymmetrical; bristles      Genus _Stephanopogon_
+         in addition to cilia
+
+      b. Body symmetrical; 4 small        Genus *_Mesodinium_
+         tentacles from mouth; cilia
+         and cirri in girdles
+
+   7. Shell composed of small             Genus *_Tiarina_
+      sculptured pieces; cilia long,
+      uniform
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LACRYMARIA Ehr. '30.
+
+(Ehrenberg, C. G., 1838; Perty '52; Claparède & Lachmann '58; Stein
+59-83; Quennerstedt '66, '67; Fromentel '74; Kent '81; Gruber '84;
+Gourret & Roeser '86; Bütschli '88; Schewiakoff '89.)
+
+Body short to very long flask-shape; for the most part contractile,
+especially in the neck region. The posterior end is rounded or
+pointed. The main character is the mouth-bearing apex, which "sets
+like a cork in the neck of the flask." One or more circles of long
+cilia at the base of the mouth portion or upon it. The body is
+spirally striped. Contractile vacuole terminal, with sometimes one
+or two further forward. Macronucleus central, globular to elongate,
+sometimes double. Food mainly bacteria. Fresh and salt water.
+
+
+Lacrymaria lagenula Clap. & Lach.  Fig. 28, a, b.
+
+Synonym: _L. tenuicula_ Fromentel '74.
+
+Body more or less flask-shape, two or three times as long as broad,
+with conical apex, which is slightly elastic and protrusible; surface
+obliquely striate, with well-defined lines, 14 to 16 in number; cilia
+uniform on the body, with a crown of longer ones at the base of the
+conical proboscis. The body cilia are not thickly placed except
+around the proboscis. The endoplasm is thickly packed with large
+granules (food particles) in the anterior half and with finely
+granular particles in the posterior half. The elongate macronucleus
+lies a little above the center among the larger granules; the
+contractile vacuole is double, one on each side of the median line
+and at the posterior end of the body among the finer granules. The
+anus is posterior. Length 90µ to 160µ; greatest width assumed 65µ.
+When fully expanded the posterior end assumes a curious polyhedral
+form. (Fig. 28 b.)
+
+This form differs slightly from others of the same species as
+described by different observers, the most striking difference being
+the presence of two contractile vacuoles in place of the usual one.
+These are very slow to fill and grow to a large size before diastole.
+The membrane is very tough and retains its form easily under pressure
+of the cover glass. Another characteristic feature is the flattening
+of the surfaces between the striæ. Decaying algæ.
+
+
+[Illustration: Fig. 28.--_Lacrymaria lagenula_.]
+
+
+Lacrymaria coronata Cl. & Lach. '58.  Fig. 29.
+
+Synonyms: _L. lagenula_ Cohn '66; Möbius '88; _L. cohnii_ ? Kent '81;
+_L. versatilis_ Quen. '67.
+
+Form flask-like and similar to _L. lagenula_, contractile but tough.
+The contractile vacuole is terminal, the proboscis is short, slightly
+raised and separated from the body by a deep cleft; the buccal cilia
+are inserted part way up on the proboscis. Form changeable, from
+short, sac-like to elongate and vermiform. Length 85µ.
+
+This species is not very different from _L. lagenula_, but I noted
+that in addition to the elongate nucleus, the body striæ are much
+more apparent here and seem to sink into the cuticle, giving the
+periphery, especially at the collar region, a curious crenulated
+effect. The endoplasm is very densely granular and colored a
+blue-green, probably from food particles. The number of striæ is much
+larger than in the preceding species. The membrane is very tough and
+retains the shape of the body, even with the full pressure of the
+cover glass. Micronucleus and trichocysts were not observed.
+
+
+[Illustration: Fig. 29.--_Lacrymaria coronata_.]
+
+
+Genus TRACHELOCERCA (Ehr. '83) Cohn '66.
+
+(Quennerstedt '67; Gruber '87; Entz '84; Kent '81; Gourret & Roeser
+'88; Bütschli '88; Schewiakoff '89; Shevyakov '96.)
+
+The only well-known representative is very elongate, large (up
+to 3 mm. Van Beneden), and very contractile. The main feature of
+importance in distinguishing it is the 4-part structure of the mouth
+region, which, however, may not be obvious. Pharynx faint and smooth.
+Contractile vacuole terminal. Macronucleus in one central body or in
+numerous pieces scattered throughout the cell.  Salt water.
+
+
+Trachelocerca phoenicopterus Cohn '66.  Fig. 30.
+
+Synonyms: _T. sagitta_ Ehr. '40, Stein '59; _T. tenuicollis_
+Quennerstedt '67, Kent '81; _T. minor_ Gruber '87, Shevyakov '96.
+
+The body is extremely elongate and ribbon-like, and this, combined
+with its wonderful power of extension and retraction, makes it one of
+the most curious and interesting of microscopic forms. The anterior
+end is square or cylindrical; the type species has a four-sided
+mouth, but many specimens may be found which have a plain cylindrical
+mouth region. One reason for this may be the fact that the extremity
+gets broken off. In one instance I noticed a very large form with the
+anterior end under some debris, which evidently held it tight, for
+the body of the ciliate was thrashing back and forth and twisting
+itself into knots, etc., like a nematode worm. Finally, the anterior
+end broke off with about one-tenth of the body; the remainder, in an
+hour, had regenerated a new anterior end with long cilia, but with
+no indication of four sides. The small anterior piece was also very
+lively, moving about and eating like the normal animal; its history,
+however; was not followed. This species appears to be variable in
+other ways as well; thus, in some cases the posterior end is rounded
+(cf. Entz '84); in others it is pointed (cf. Kent '81, Cohn '66, et
+al.).
+
+Again, the macronucleus may be a single round body (Entz '84,
+Bütschli '88) or in two parts (Kent '81), or in many parts scattered
+about the body (Gruber). In the Woods Hole forms the tail is
+distinctly pointed and turned back sharply, forming an angle at the
+extremity. The cilia on this angular part are distinctly longer than
+the rest. The function of this posterior part is apparently to anchor
+the animal while it darts here and there upon the tail as a pivot,
+contracting and expanding the while. The body is finely striated
+with longitudinal markings; when contracted there are no transverse
+markings nor annulations. The nucleus is in the form of many
+fragments scattered throughout. Length of large specimen 1.7 mm.
+
+
+[Illustration: Fig. 30.--_Trachelocerca phoenicopterus_.]
+
+
+Genus MESODINIUM Stein '62.
+
+(Maupas '82, '84; Entz '84; Shevyakov '96.)
+
+The main part of the body is globular or conical, with a short,
+platform-like oral region, and a deep annular groove about the
+middle of the body. The oesophagus is rather long, and smooth or
+longitudinally striped. One or more rings of cirri rise in the
+groove. If more than one ring of cirri are present, the anterior set
+usually point forward and lie close to the anterior part of the body.
+The posterior set, on the other hand, cling close to the posterior
+region of the body and give to it a peculiar encapsuled appearance.
+The most characteristic feature is the presence of four short
+tentacle-like processes which can be protracted and retracted from
+the oral region. (Mereschowsky says that the entire anterior half
+is more or less contractile.) The macronucleus is horseshoe-shaped
+or ovoid and is situated in the posterior half of the body. The
+contractile vacuole is also posterior.
+
+Movement consists in rapid swimming, with rotation on its axis, or
+in creeping by means of its anterior cirri, or in sudden jumping, by
+which it apparently clears a distance of 20 times its diameter in one
+bound. Mouth parts may also be used for attachment to foreign bodies.
+The moving periods alternate with quiescent periods, during which the
+organisms with their outstretched and radiating cirri resemble the
+heliozoön _Actinophrys_.
+
+
+Mesodinium cinctum, n. sp.  Fig. 31.
+
+Body spherical to pyriform, constricted near the middle, the
+constriction dividing the body into dissimilar parts. The anterior
+part is broadly pyriform, somewhat plastic and hyaline, with an oral
+extremity which is sometimes hollow, sometimes evaginated and convex.
+Upon this flexible anterior part there are four short but distensible
+tentacles. The posterior part is granular and usually filled with
+food particles; it is well rounded and holds the nucleus and
+contractile vacuole. The entire body is surrounded by a fine cuticle.
+The nucleus is elongate and extends through the greater part of the
+posterior half. The contractile vacuole lies on one side, near the
+girdle. The mouth is on the anterior pole in the tentacle region. The
+motile organs are cirri and cilia, all inserted in the constriction.
+There are two sets of cirri and one of cilia; the latter stand out
+radially from the girdle and are usually in motion. The cirri of
+one set, the anterior, extend forward about twice the length of the
+anterior half; those of the posterior set closely engirdle the lower
+half, reaching not quite to the posterior extremity. These are
+somewhat hyaline and are closely approximated, giving the impression
+of a tight-fitting crenulate casing about the lower half. The cirri
+are sharply pointed, much broader at the base, and the two sets are
+so placed that, looked at from above, they have the appearance of a
+twisted cord. (Fig. 31 b.) Movement erratic; sometimes the animal
+swims steadily forward with mouth in front; again it shoots across
+the field of the microscope, either backward or forward or sideways,
+through the action of its powerful cirri. It is often quiet, usually
+mouth downward, and is held in place by adhesion of the tentacles. In
+this position it looks strikingly like a heliozoön.
+
+Length 35µ; greatest width 30µ. Not uncommon.
+
+The chief features by which this species is distinguished from the
+frequently described _M. pulex_ of Europe are the number of anterior
+cirri and the ring of true cilia in place of the central girdle of
+cirri. The European form is described with four anterior bristles;
+the present form has from 28 to 32. The radial cilia differ decidedly
+from the more powerful cirri and they are not in one plane, so that
+counting is difficult; they are not closely set. The presence of
+tentacles makes these forms of especial theoretical interest,
+especially in the light of the origin of _Suctoria_.
+
+
+[Illustration: Fig. 31.--Side and top views of _Mesodinium cinctum_.]
+
+
+Genus TIARINA R. S. Bergh '79.
+
+(Claparède & Lachmann '58.)
+
+Body subcylindrical, pointed posteriorly, two and one-half times
+as long as broad; encased in covering composed of separate pieces
+arranged in five girdles. The pieces bear processes which rest
+against neighboring pieces of the girdle. Mouth large, anus terminal
+near contractile vacuole. The macronucleus is simple and round. Salt
+water.
+
+
+Tiarina fusus (Cl. & Lach.) emend R. S. Bergh.
+
+Synonyms: _Coleps fusus_ Cl. & Lach. '58; Daday '86; Möbius '88,
+Lauterborn '94; Shevyakov '86.
+
+This form, which resembles _Coleps_ rather closely, was placed as a
+separate genus by R. S. Bergh. The skeletal parts consist of five
+zones of needles composed of an organized substance and embedded in
+the cortical plasm, the last zone coming to a point at the posterior
+end. The needles have lateral processes, which give a latticed
+appearance to the casing. The cilia are long, with a specialized
+crown of still longer ones at the oral end; they arise outside of the
+skeletal elements and do not pass between them, as in _Coleps_.
+
+
+KEY TO MARINE GENERA OF TRACHELINIDÆ.
+
+Diagnostic characters: Body bilateral, or asymmetrical by local
+prolongations; usually compressed or flattened laterally, the left
+side more convex than the right. The essential feature is the
+position and character of the mouth. This is either a long slit
+extending from the anterior end well down the ventral surface, or the
+posterior part only of a ventral furrow remains open as a round or
+elongate mouth some distance from the anterior end. The entire mouth
+region of the body is usually drawn out into an elongate tapering
+proboscis which is generally curved dorsally at the extremity.
+An oesophagus is short or absent altogether; when present it is
+supported by a stiff buccal armature. Cilia are uniform about entire
+body or limited to the flat right side. Food is swallowed.
+
+1. a. Proboscis easily distinguished      2
+      from the main body
+
+   b. Proboscis not marked off from       Genus *_Loxophyllum_
+      main body; body flat;
+      both surfaces striated
+
+2. a. Mouth runs the entire length        Genus _Amphileptus_
+      of proboscis; entire body
+      uniformly ciliated
+
+   b. Mouth runs the entire length        Genus *_Lionotus_
+      of proboscis; body flat; right
+      side only is ciliated
+
+   c. Proboscis much drawn out,           Genus _Dileptus_
+      flexible; mouth at its base
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LOXOPHYLLUM Dujardin '41.
+
+(Duj. '41; Wrzesniowski '69; Quennerstedt '65; '67; Cohn '66; Entz
+'84; Gourret & Roeser '88; Bütschli '88; Shevyakov '96.)
+
+The body is flat and somewhat leaf-shape, flexible, and elastic. The
+anterior end is somewhat proboscis-like and flexible, but is not
+sharply demarcated as in _Lionotus_. The central portion of the body
+is developed into a more or less arched dorsal mass, which usually
+contains the nuclei and contractile vacuoles. As a result of this
+local thickening, the body is surrounded by a thin hyaline margin.
+This, however, may be absent on the right side in some species. The
+mouth reaches from the anterior extremity to a short distance from
+the end, and usually approaches the left edge. An anus is present
+near the posterior end of the dorsal swelling. Trichocysts are
+numerous on the ventral surface, and often on the dorsal surface,
+where they are inclosed in minute papilla-like swellings.
+Cilia-distribution controverted. Maupas and Bütschli hold that
+ventral surface alone is ciliated; others (Kent and Dujardin) that
+cilia are uniformly distributed. The entire body, dorsal and ventral
+surfaces alike, are uniformly striated. The contractile vacuole lies
+posteriorly, on the right side and in the dorsal swelling. In the
+fresh-water form _L. meleagris_, it is connected with a long canal
+whose swellings are frequently taken for additional contractile
+vesicles (Bütschli); in the marine form described below the canal is
+not developed and a series of vacuoles takes its place; these are
+all contractile. The macronucleus may be single, double, quadruple,
+band-formed, or rosette-formed. Movement is steadily progressive and
+peculiarly gliding. Fresh and salt water.
+
+
+Loxophyllum setigerum Quenn. '67.
+
+Synonyms: _Litosolenus armatus_ Stokes '93; _Litosolenus verrucosa_
+Stokes '93.
+
+The body is flattened, irregular in outline, obtusely pointed
+anteriorly, the point being turned to the right; rounded posteriorly.
+The left edge is nearly straight, the right considerably arched with
+a few setæ on the posterior half. Contractile vacuoles are numerous,
+dorsal in position and on the right side. The macronueleus is beaded,
+the several spheres connected.
+
+
+Variety armatum (Cl. & Lach.) Fig. 32.
+
+Under the name _Litosolenus armatus_, Stokes described a form from
+brackish water near New York, which should unquestionably be referred
+to the genus _Loxophyllum_, and I believe to Quennerstedt's species
+_setigerum_. While the latter possesses only a few setæ, the former
+has a number of them, and Stokes described his species as having a
+variable number. For this reason I include the Woods Hole form under
+the tentative name _armatum_, as a variety of Quennerstedt's _L.
+setigerum_. The flat margins are distinctly striated longitudinally,
+and faintly marked radially, on the dorsal surface. Longitudinal
+elevated striæ also run the length of the dorsal hump and upon the
+entire ventral surface. The ventral surface is alone ciliated. Upon
+the edges of the flat border are sharp-pointed, colorless, spine-like
+processes, situated at equal distances around the entire periphery
+except at the anterior end. Each spine is thick at the base and
+tapers to a full point which is curved upward--_i. e._, dorsally
+(fig. 32, a, b). The entire body is plastic and contractile, turning
+its leaf-like edge readily over objects upon which it creeps. The
+cilia are fine and uniform, with a tendency to lengthen in the oral
+region.
+
+Length 100µ; greatest width assumed on contraction 85µ; when normal
+about 50µ.
+
+
+[Illustration: Fig. 32.--_Loxophyllum setigerum_, var. _armatum_. a,
+b, c, ventral, dorsal, and lateral aspects.]
+
+
+Genus LIONOTUS Wrzesniowski '70.
+
+(Incorrectly called _Litonotus_ by many. Entz '84; Gruber '84;
+Bütschli '88; Kent '81; Schewiakoff '89; Shevyakov '96.)
+
+The body is elongate and somewhat lance-shaped, widest at the central
+part and tapering to a point at the anterior end. The posterior end
+may be similarly tapered or rounded. The anterior end frequently
+proboscis-like, flat, and flexible, while the entire body is more or
+less elastic and contractile.  The right side is flattened and alone
+provided with cilia, while the left side of the body proper is
+arched; on the left side of the proboscis is a row of coarse cilia
+resembling an adoral zone, and a row of trichocysts. A long peristome
+stretches down the thin, ventral side of the proboscis, and the mouth
+proper is situated at the junction of the proboscis and body; the
+mouth, as a rule, is invisible. The ciliated right side alone is
+striated in the majority of species. The contractile vacuole may be
+single or multiple, usually in the posterior region of the body and
+dorsal in position. The macronucleus is usually double, rarely single
+or quadruple, but may occasionally break into numerous smaller
+pieces.  Movement, free-swimming or gliding, with especial tendency
+to get under clumps of foreign matter.
+
+Fresh and salt water.
+
+
+Lionotus fasciola Ehr.  Fig. 33.
+
+Synonyms. _Amphileptus fasciola_ Ehr. '38; Dujardin '41; Lachmann
+          '56;  Cohn '66, Diesing '65.
+          _Loxophyllum fasciola_ Claparède & Lachmann '58;
+          Balbiani '61.
+          _Loxophyllum duplostriatum_ Maupas '83. Shevyakov '96.
+
+Body frequently brown or brilliant yellow in color, somewhat sigmoid
+in form with tapering anterior end, the extremity of which is turned
+dorsally. The proboscis is about half the entire length and is not
+sharply marked from the rest of the body but tapers gradually, its
+base being equal to the diameter of the body at its middle point. The
+body is slightly contractile and the posterior end is carried to a
+rounded point, but not into a distinct tail. Unlike the fresh-water
+variety, this one has no hyaline margin nor hyaline caudal region,
+and the contractile vacuole is double or multiple on the dorsal side
+near the posterior end. Cilia are present only on the under (right)
+side, with, however, a row of large cilia marking the course of the
+elongate mouth, upon its left side. The right side is striated, the
+left arched and without markings. The endoplasm is finely granular
+with, however, larger food particles in the process of digestion,
+while specimens are occasionally seen with the natural form
+completely lost through distortion caused by over-large captures (Cf.
+also Wrzesniowski '70, p. XXIII, fig. 32). Movement continuous, slow,
+and gliding; very little tendency to jerking movements. Macronucleus
+double, both parts spherical, and placed in about the center of the
+larger part of the body; closely approximated but not, as Schewiakoff
+described, connected. In conjugation, a large form unites with a
+smaller one, the mouth parts being connected. Details of conjugation
+and macronuclei not made out. Length 200µ to 600µ.
+
+
+[Illustration: Fig. 33.--_Lionotus fasciola_.]
+
+
+KEY TO MARINE GENERA OF CHLAMYDODONTIDÆ.
+
+Diagnostic characters: Form usually ellipsoid, never very elongate.
+Transverse section of body circular or elliptical. The mouth is
+usually some distance from the anterior end and may be in the
+posterior part. Sometimes it is in the center of the ventral
+surface, again on the right side. The oesophagus invariably has
+a well-developed buccal armature, or a smooth peculiarly built
+oesophageal tube. Food particles of large size.
+
+1. Body cylindrical. Cilia about          Genus *_Nassula_
+   entire body
+
+   Body flat                              2
+
+2. a. Without a caudal process            3
+
+   b. With a caudal process               5
+
+3. a. Anterior end angular                4
+      on left side
+
+   b. Anterior end rounded                Genus _Chlamydodon_
+
+4. a. Dorsal striæ and cilia present,     Genus _Orthodon_
+      ventral cilia longer
+
+   b. Dorsal striæ and cilia absent;      Genus *_Chilodon_
+      posterior end not pointed
+
+   c. Dorsal striæ and cilia absent;      Genus _Scaphidiodon_
+      posterior end pointed
+
+5. a. Caudal spine with posterior         6
+      bristle-like cilia
+
+   b. Caudal spine without posterior      Genus _Trochilia_
+      bristle-like cilia;
+      ventral cilia reduced
+
+6. a. With pigment spot on anterior       Genus _Ægyria_
+      angle
+
+   b. Without such pigment spot           Genus _Onychodactylus_
+
+   c. Cilia on right edge only of         Genus *_Dysteria_
+      greatly reduced ventral surface
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus NASSULA Ehr. '33
+
+(Dujardin '41; Stein '67; Cienkowsky '55; Cohn '66; Clap. et Lach.
+'58; Kent '81; Maupas '83; Entz '84; Fabre-Domergue '88; Bütschli
+'88; Shevyakov '96.)
+
+The body is ovoid or cylindrical, with well-rounded ends, and in
+some cases slightly flattened. The mouth is ventral and placed some
+distance from anterior end (1/4 to 1/3 total length). A slight
+depression on the ventral surface marks the mouth region, which is
+further indicated by larger and more powerful cilia. The rest of the
+body is uniformly ciliated. The entire body is marked by clearly
+defined spiral stripes. The mouth is circular and the oesophagus is
+supported by a considerable armature, which usually extends dorsally
+and to the left, rarely to the right. In some cases the structure of
+this armature is indistinct; again it can be clearly seen to consist
+of definite rods (Stäbchen). The anus is probably always terminal.
+Contractile vacuoles are variable in different species. In some cases
+there is but one, which is placed at the posterior end or centrally
+on the ventral side; in others there may be four--two dorsal and
+two ventral. In many cases trichocysts are uniformly distributed.
+Sometimes the body is colorless; again, and more often, it is
+brightly colored with red, blue, brown, or black pigment. The
+macronucleus is globular and central, occasionally band-form and
+with numerous attached micronuclei. Food substance varied, usually
+vegetable matter, see, however, below. Cysts are globular. Movement
+is a steady progression, combined with rolling.
+
+
+Nassula microstoma Cohn '66.  Fig. 34.
+
+Synonyms: _Paramoecium microstomum_ Cl. et Lach. '58, Gourret et
+Roeser '88; _Isotricha microstomum_ Kent '81.
+
+Body subcylindrical, rounded at each extremity, not quite twice as
+long as broad. A slight depression on one surface marks the position
+of the mouth, this depression being indicated by a row of longer
+cilia. The mouth is extremely small and is surrounded by a curious
+buccal armature. This is not made up of bars or rods, as in most
+species of _Nassula_, but appears perfectly smooth and uniform
+except for the considerable swelling at the inner end. The cuticle is
+firm and unyielding and marked by longitudinal and somewhat spiral
+rows of cilia and trichocysts. Under the microscope this is one of
+the most pleasing forms found at Woods Hole. Its color is yellowish
+brown from the presence of brilliant particles of coloring matter
+held in the cortical plasm, and, as it slowly rolls along, these
+particles and the black trichocysts give to the organism a peculiar
+sparkling effect. The macronucleus is almost central; the contractile
+vacuole posterior. The endoplasm appears well filled with food
+bodies, some of which could be distinguished as _Amphidinium_ and
+_Glenodinium_.
+
+Length 55µ; greatest diameter 30µ.
+
+
+[Illustration: Fig. 34.--_Nassula microstoma_.]
+
+
+Genus CHILODON Ehr.
+
+(Dujardin '41; Engelmann '78; Stein '54, '58; Kent '81; Bütschli '88;
+Gruber '83; Cienkowsky '55; Möbius '88; Clap. et Lach '58;
+Wrzesniowksi '65; Shevyakov '96.)
+
+Small forms, greatly flattened dorso-ventrally and almost egg-form in
+outline. The anterior end is bent distinctly to the left and forms a
+characteristic process, which, together with the entire margin of the
+body, is soft and flexible. The posterior end is, as a rule, broadly
+rounded. The ventral surface is finely striate, and this surface
+alone is ciliated. The lines of cilia converge at the mouth, and at
+this region the cilia are somewhat larger and more distinct, thus
+forming a functional adoral zone. The mouth is median and is situated
+in the anterior half of the body. It is surrounded by a well-defined
+armature, composed usually of from 10 to 16 rods. The contractile
+vacuoles are quite varied and from one to many in number, the
+number increasing with the size of the individual. The macronucleus
+is usually single, elliptical in form, and centrally placed;
+one micronucleus. Reddish granular pigment and trichocysts are
+occasionally present.
+
+
+Chilodon cucullulus Müll., sp.  Fig. 35.
+
+Synonyms; _Colpoda cucullus_ O. F. Müller; _Loxodes cucullulus_;
+_Chilodon uncinatus_ Ehr. '58, Perty '52, Dujardin '41; _L. dentatus_
+Duj., etc.
+
+This extremely variable form has received so many different names
+that it hardly pays to enumerate them. It is one of the commonest
+and most widely spread ciliates known, although at Woods Hole I was
+surprised to see it so rarely. It is the type species of the genus
+and needs no further description. The specimens observed at Woods
+Hole had numerous contractile vacuoles and were 42 to 45µ long and
+from 28 to 32µ wide.
+
+
+[Illustration: Fig. 35.--Ventral and dorsal aspects of _Chilodon
+cucullulus_.]
+
+
+Genus DYSTERIA Huxley '57.
+
+(Cl. et Lach. '58; Entz '84; Möbius '88; Shevyakov '96.)
+
+Small forms, firm in outline, and colorless or slightly colored. The
+body is somewhat clam-shaped, flattened, slightly curved or straight
+on the right side, the other more convex. The true ventral side is
+only a narrow strip along the right and anterior edge of the body,
+the apparent ventral side being a fold of the very large dorsal
+surface which comes around ventrally, forming a valved structure
+somewhat analogous to a clam shell. Cilia are limited to the outer
+edge of the small ventral surface, which also bears a peculiar spine
+at the posterior end. Behind this spine are larger cilia. The mouth
+opening lies in the anterior widened portion of the ventral surface
+and is connected with a smooth tubular pharynx. The right half of the
+dorsal side, _i.e._, the apparent dorsal side, is arched and bears
+longitudinal ridges. Two to four contractile vacuoles are placed on
+the ventral side. The macronucleus is usually dorsal, elliptical, and
+cleft, with one micronucleus attached. Fresh and salt water.
+
+
+Dysteria lanceolata Cl. et Lach.  Fig. 36.
+
+Synonym: _Cypridium lanceolatum_ Kent '81.
+
+Outline of the flattened body ovoid; body consists of two valve-like
+portions; the edge of the right valve is nearly straight, that of the
+left valve more or less sinuous; anteriorly it is cut away, obliquely
+and posteriorly it has a deep indentation in which the seizing spine
+rests. The cilia are confined to the ventral surface, here reaching,
+however, from the anterior dorsal extremity to below the posterior
+indentation. Posteriorly the cilia become larger, corresponding to
+the larger cirri of _D. armata_, which are posterior to the spine.
+The mouth lies between the two valves and is surrounded by a long
+and smooth buccal armature which passes downward and backward to
+the left a distance equal to about half the entire body length. The
+macronucleus is situated in the dorsal region in the central part of
+the body. There are two contractile vacuoles, one behind the center
+of the buccal armature, the other near the inner end of this organ.
+Movement is in circles, the animal moving around quite rapidly when
+not attached by its posterior process. It is colorless and measures
+45µ in length by 27µ in width. Claparède & Lachmann and Shevyakov
+describe it as 70µ long.
+
+
+[Illustration: Fig. 36.--_Dysteria lanceolata_.]
+
+
+KEY TO MARINE GENERA OF CHILIFERIDÆ.
+
+Diagnostic characters: Mouth never lies behind the middle of the
+body; the oesophagus is but slightly developed. The undulating
+membranes are placed either on the edge of the mouth or in the
+oesophagus. A peristomial depression leading to the mouth is absent
+or very slightly indicated.
+
+1. Mouth in the anterior half,            Genus *_Frontonia_
+   undulating membrane on left edge
+   only; right edge continued in a
+   long ventral furrow
+
+2. Two undulating membranes; mouth        Genus *_Colpidium_
+   central; no caudal bristles
+
+3. Two undulating membranes; caudal       Genus *_Uronema_
+   bristle
+
+
+Genus FRONTONIA Ehr. (Cl. & Lach. '58?).
+
+(Ehrenberg, subgenus of _Bursaria_ '38; Claparède & Lachmann '58;
+Bütschli '88; Shevyakov '96.)
+
+Form elongate and cylindrical, or often flattened dorso-ventrally,
+with round or pointed ends. It is usually plastic and contractile.
+Cilia are evenly distributed about the body and are similar in
+length. The large, open mouth lies on the anterior half of the
+ventral surface, and is elongate and oval in outline. On its left
+edge is a well-defined membrane which stretches across to the right
+side of the mouth. On the right edge is a small, longitudinally
+striped tract which is free from trichocysts and smooth in
+appearance. This tract is continued posteriorly in a long furrow,
+which in some cases reaches the posterior end of the animal. A few
+rows of cilia in this furrow vibrate differently from the others and
+give the effect of a membrane (Bütschli). The oesophagus is extremely
+short and hard to make out. The body is usually covered uniformly
+with trichocysts, often of considerable size. There are 1 or 2
+vacuoles with long canals radiating throughout the endoplasm. The
+macronucleus is oval and centrally placed. Micronuclei vary from
+one to many. An anal opening is placed at the end of the long
+ventral furrow. The plasm is colorless or green by the presence of
+Zoochlorella, or colored brown or black by pigments. In these cases
+there is a considerable pigment mass on the anterior end. Movement
+is regular, forward, and combined with rotation. Food consists of
+foreign objects, diatoms, other protozoa and the like. Fresh and salt
+water.
+
+
+Frontonia leucas Ehr.  Fig. 37.
+
+Synonyms: _Frontonia vernalis_ Ehr. '38; _Bursaria leucas_ Allman
+'55, Carter '56; _Panophrys leucas_ Duj. '41, Stein '67; _Panophrys
+vernalis_ Dujardin '41, Stein '67; _P. chrysalis_ Duj. '41, Fromentel
+'74; _Cyrtostomum leucas_ Stein '67, Kent '81.
+
+Form ovoid, elongate, occasionally a little flattened
+dorso-ventrally. Mouth in the anterior third of the body. The left
+edge of the mouth carries a distinct undulating membrane; the right
+edge is plain, longitudinally striated and bears cilia. It is
+slightly depressed and the depression is carried posteriorly in the
+form of a shallow furrow which reaches to the posterior end. The
+contractile vacuole is on the left side, the spheroidal nucleus on
+the right side of the furrow. The body is uniformly covered with fine
+cilia, and the periphery is uniformly studded with large trichocysts,
+except along the furrow. Food consists of dinoflagellates and other
+small forms. Color dark brown to black.
+
+Length 330µ; width 200µ.
+
+This form differs considerably from the fresh-water _Frontonia
+leucas_ as described by Schewiakoff '89, especially in the extreme
+length of the peristomial furrow, in the position of the nucleus and
+contractile vacuole, and in the nature of the water canals. These
+in the Woods Hole form are very irregular in size and very much
+branched, not uniform as in Lieberkühn's (see Bütschli) figure of
+_Frontonia leucas_, nor radiating as in Schewiakoff's description.
+This may be the same species as _Frontonia marina_, of Fabre-Domergue
+'91, whose description and figure I have not seen.
+
+
+[Illustration: Fig. 37.--_Frontonia Leucas_.]
+
+
+Genus COLPIDIUM Stein '60
+
+(Bütschli '88; Maupas '83.)
+
+The general form is oval, slightly compressed laterally with the
+dorsal side strongly arched. The ventral side is slightly incurved.
+The anterior end is somewhat smaller than the posterior end, which is
+broadly rounded. The mouth is placed some distance from the anterior
+end in an oral depression and opens into a tubular oesophagus. There
+are usually two undulating membranes which do not extend beyond the
+mouth borders. The right undulating membrane extends down into the
+oesophagus and appears to be attached to the walls of the latter. The
+body stripes in front of the mouth are twisted to the left. The anus
+is terminal and the contractile vacuole may be terminal or situated
+forwards in the dorsal region. The macronucleus is spherical and
+has one  micronucleus attached. Food consists mainly of bacteria.
+Movement rapid, but interrupted.
+
+Fresh and salt water, common in infusions.
+
+
+Colpidium colpoda Ehr., sp.  Fig. 38.
+
+Synonyms: _Colpidium cucullus_ Kent '81; _C. striatus_ Stokes '85;
+_Kolpoda cucullus_ Duj. '41; _Paramoecium colpoda_ Ehr. '38,
+Quennerstedt '67; _Plagyiopyla nasula_ Kent '81, G. & R. '86;
+_Glaucoma pyriformis_ G. & R. '86; _Tillina campyla_ Stokes '85, '88.
+
+The body is oval, somewhat larger posteriorly, and a little
+compressed dorso-ventrally. The anterior end is twisted a little from
+the right to the left (more evident in fresh-water forms), and leans
+somewhat toward the ventral side. Under this portion, on the ventral
+side, lies the mouth in a large depression just above the middle of
+the body. The entire body is covered with uniform and delicate cilia,
+which are placed in longitudinal rows. These rows are almost straight
+on the dorsal side, but bend on the ventral surface, following
+the contour of the twisted anterior portion. The endoplasm is
+finely granular; the oesophagus leading into it is very distinct.
+Schewiakoff ('89) describes two membranes, an inner and an outer;
+Maupas ('83) describes them as right and left. In the present species
+I was able to make out only one. The macronucleus is central,
+spherical in form, and bears a single minute micronucleus. The
+contractile vacuole is posterior and dorsal to the long axis of the
+body. The anus is ventral to this axis and also posterior. Length
+45µ, width 20µ. Common.
+
+This marine variety is much smaller than the fresh-water form and the
+form differs in a number of respects, viz, in the anterior torsion
+and in the structure of the mouth. These may be, however, only
+individual variations of a widely spread species, and I believe it is
+perfectly safe to describe this as _Colpidium colpoda_.
+
+
+[Illustration: Fig. 38.--_Colpidium colpoda_.]
+
+
+Genus URONEMA Duj. '41.
+
+(Quennerstedt '69; Cohn '66; Kent '81; Bütschli '81; Schewiakoff '89;
+Shevyakov '96.)
+
+Minute forms; colorless and constant in body form. The form is oval,
+slightly compressed on the ventral side, while the dorsal side is
+distinctly arched. The membrane is distinctly marked by rather widely
+separated striæ. These occasionally have a spiral course about the
+body; in all cases they can be easily counted. The mouth is large
+and placed near the center of the ventral surface. It is sometimes
+approached by a very shallow depression or peristome from the
+anterior end, and marked by two rows of cilia. An undulating membrane
+extends down the mouth. Oesophagus absent. A long, stiff bristle
+extends outwards from the posterior end. The contractile vacuole is
+terminal or subterminal and near the anal opening. The macronucleus
+is spherical, centrally placed, and with one micronucleus closely
+applied. Movement is rapid and usual forwards in a straight line,
+often found resting, however, with outstretched cilia in contact with
+some foreign body. Food mainly bacteria. Fresh and saltwater, usually
+in decomposing vegetable substances.
+
+
+Uronema marina Duj.  Fig. 39.
+
+Synonyms: _Enchelys triquetra_ Dujardin; _E. corrugata_ Duj.;
+_Cryptochilum griseolum_ Maupas '83; _Philaster digitiformis_
+Fabre-Domergue '85.
+
+Small animals with ellipsoidal form and about twice as long as
+broad. The mouth lies in the upper half of the body and bears a
+well-developed undulating membrane upon its left edge. The membrane
+is longitudinally striped and covered with long and vibratile cilia.
+The right edge of the mouth bears cilia which are about the same in
+size as the body cilia, but are more closely inserted (Schewiakoff).
+The most characteristic feature is the long caudal bristle, which
+is extremely delicate and about two-thirds the length of the body.
+Schewiakoff thinks this bristle has a sensory function. I could not
+make this out, for although other protozoa ran against this bristle,
+often bending it well over to one side, the animal showed no sign
+of irritability but lay quiescent. A spherical macronucleus with
+attached micronucleus lies in the center of the body. The contractile
+vacuole is posterior in front of the bristle. The macronucleus was
+found to be double, as though just divided, in a large percentage of
+cases. This may be a precocious division of the nucleus long before
+signs of the body division are evident. Such a phenomenon, however,
+is rare, the macronucleus usually dividing at a late stage of cell
+division. Length 30 to 50µ; width 15 to 20µ. Common in decomposing
+algæ.
+
+
+[Illustration: FIG. 39.--_Uronema marina_.]
+
+
+KEY TO MARINE GENERA OF PLEURONEMIDÆ.
+
+Diagnostic characters: The mouth is at the end of a long peristome
+running along the ventral side; the body is dorso-ventrally or
+laterally compressed. The entire left edge of the peristome is
+provided with an undulating membrane which occasionally runs around
+the posterior end of the peristome to form a "pocket" leading to
+the mouth. The right edge of the peristome is provided with a
+less-developed membrane. There may or may not be a well-developed
+pharynx.
+
+Body small; not produced into             Genus *_Pleuronema_
+ neck-like elongation
+
+Body medium-sized; anterior end           Genus *_Lembus_
+produced into neck-like elongation
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PLEURONEMA Dujardin '41.
+
+(Perty '52; Clap. & Lach. '58; Stein '59, vol. I; Quennerstedt '67;
+Kent '81; Bütschli '88; Schewiakoff '89; Shevyakov '96.)
+
+Small to medium-sized ciliates, with an unchanging form. They are
+somewhat lens-shape and laterally compressed, the two surfaces
+about equally arched. The ventral surface is nearly straight or
+but slightly arched; the dorsal is quite convex.  The anterior and
+posterior extremities are equally rounded.  The peristome begins as
+a small depression, but becomes larger until it takes in nearly all
+of the ventral surface. The depression becomes much deeper at about
+the center of the body, and is especially marked on the left side of
+the peristome. In this deeper portion is the mouth, with an almost
+imperceptible oesophagus. Upon the left edge of the peristome is a
+high, undulating membrane, sail-like in appearance when extended.
+This may stretch around the posterior edge of the peristome and upon
+the right aide, thus forming a pocket by means of which the food
+particles are directed into the mouth. The rest of the right edge
+of the peristome is occupied by closely approximated powerful cilia
+(Bütschli) or a second undulating membrane (Stein). The body cilia
+are relatively long. Trichocysts and caudal bristles may be present.
+The contractile vacuole is subterminal and dorsal; it is questionable
+whether there are canals leading to it. A round macronucleus with
+one micronucleus is in the anterior half of the body. The anus is
+terminal. Food is chiefly bacteria. Movement combines springing with
+swimming and rotation. Fresh and salt water.
+
+
+Pleuronema chrysalis Ehr., sp.  Fig. 40.
+
+Synonyms: _Pleuronema crassa_ Dujardin '41; _P. marina_ Duj. '41;
+Fabre-Domergue '85; _P. coronata_ Kent '81; _Paramoecium chrysalis_
+Ehr. '38; _Lembadion orale_ G. & R. '88; _Histiobalantium agile_
+Stokes '85, '88.
+
+The body is ovoid, slightly flattened, rounded at both ends, the
+anterior end sharper than the posterior. The ventral surface is
+almost entirely taken up by a peristome which extends from the
+anterior end posteriorly three-quarters of the body length. The
+posterior end of the peristome is straight, the left curved,
+following the depressed portion. The body is covered with fine cilia
+in longitudinal lines, except on the peristome. The mouth is small
+and situated in the hollow of the peristome near the left border. On
+the left peristome edge is a large undulating membrane. It begins
+near the anterior end of the body and increases in height posteriorly
+following the peristome edge around on the right side. This posterior
+bend of the membrane causes the appearance of a full sail, so
+often seen. It can be entirely withdrawn and folded together in
+the peristome. On the right edge of the peristome are large,
+powerful cilia. The contractile vacuole is central and dorsal; the
+macronucleus is in the anterior half of the body, with one attached
+micronucleus. Food consists of bacteria. Not very common. Fresh
+and salt water. It often remains quiet, with membrane and cilia
+outstretched, as though dead, but suddenly gives a spring and is
+gone.
+
+
+[Illustration: Fig. 40.--_Pleuronema chrysalis_.]
+
+
+Pleuronema setigera, n. sp.  Fig. 41.
+
+Body colorless, elongate, and with the general form of a cucumber,
+the posterior end being somewhat pointed. The mouth and relatively
+small peristome are situated in the lower third of the body. The
+peristome begins as a shallow furrow at the center of the ventral
+surface and dips sharply into the buccal depression, which is deep
+and turned toward the posterior end. The left edge of the peristome
+bears a high undulating membrane, which extends anteriorly only
+as far as the center of the body; posteriorly it passes around to
+the right edge of the peristome, thus forming the characteristic
+membranous pocket. Inside the oral depression is a second undulating
+membrane, running down to the mouth. This is small and without an
+oesophagus. The body is clothed with long setose cilia which are
+frequently fully outstretched when the animal is resting, a slight
+tremor of the large membrane alone indicating vitality. Posteriorly
+these appendages are drawn out into long filiform setæ, the number
+varying in different individuals from three to nine or ten. These
+are extremely fine and difficult to see without a high power (_e.g._
+1/12 oil) and careful focussing of the substage condensor. Like _P.
+chrysalis_, the resting periods are terminated by sudden springs,
+otherwise the movements are steady and forward. The macronucleus is
+central, and the contractile vacuole posterior and terminal. Length
+45µ to 50µ; greatest diameter 17µ. In decaying algæ.
+
+It was this form, I believe, that Peck '95 described as a "ciliate."
+
+
+[Illustration: Fig. 41.--_Pleuronema setigera_.]
+
+
+Genus LEMBUS Cohn '66.
+
+(Cohn '66; Quennerstedt '69; Kent '81; Fabre-Domergue '85; Gourret &
+Roeser '88; Bütschli '88; Shevyakov '96.)
+
+Free-swimming animals of elongate form, more or less elastic, and
+flexible, bending readily to avoid obstacles, etc. The anterior half
+is usually drawn out into a slightly curved neck-like portion. The
+peristome is a small groove leading from the anterior end to the
+mouth about midway down the ventral side of the body. Bütschli,
+following Quennerstedt, describes an undulating membrane on each side
+of the peristome groove. Other observers, however, usually describe
+but one, the left, which is clearly defined and stretches out some
+distance from the body, while the right border is described as having
+smaller but very active cilia. The general body surface is clothed
+with fine, uniform cilia, and body striæ are usually absent. One
+or more caudal bristles may be present. The contractile vacuole is
+posterior and terminal, and may be multiple. The macronucleus is
+spherical and perhaps double (Kent). Food is chiefly bacteria, and
+the animals are frequently found with the anterior end embedded in
+zoogloea masses. Salt water, usually in infusions.
+
+
+Lembus infusionum, n. sp. Fig. 42.
+
+The body is elongate, lancet-shaped, with a tapering anterior
+extremity. The dorsal outline is concave through the bending of the
+anterior end, while the ventral outline presents an even, convex
+curve. The mouth lies slightly above the center of the body and marks
+the posterior limit of the ventral peristomial groove, which curves
+slightly from the anterior extremity. Each side of this groove bears
+an undulating membrane, the left being much larger and conspicuously
+striated. The general form of this left membrane is triangular,
+the widest part is anterior, the narrowest at the mouth. The
+right membrane is similar in form, but smaller and more active.
+The endoplasm is colorless and finely granular, not regionally
+differentiated. The ectoplasm consists of a relatively thick cortical
+plasm specially noticeable in the posterior half of the body and
+a delicate cuticle which bears almost imperceptible longitudinal
+markings--the insertion points of the fine cilia. The body is covered
+with uniform cilia except at the anterior extremity. Here they are
+much larger and bristle-like. I was unable to find any cilia in the
+peristome. One long caudal bristle, one-quarter of the length of the
+body, trails out behind. The macronucleus is spheroidal and placed
+near the center of the body; a conspicuous micronucleus lies near it.
+A row of contractile vacuoles extends from the posterior end. I have
+seen as many as six of nearly equal size and one or two smaller ones.
+The intervals of contraction are quite long. Length 70 to 75µ;
+greatest diameter 10 to 12µ.
+
+_L. infusionum_ resembles _L. elongatus_ in its general form and in
+its mode of life, for it excavates a retreat in zoogloea masses and
+lies there for considerable periods perfectly quiet. It differs
+from _L. elongatus_ and from _L. velifer_ (probably the same as _L.
+elongatus_ of Claparède & Lachmann) in the presence of the caudal
+bristle, in the absence of annular markings, number of contractile
+vacuoles, and in the slightly smaller size. It resembles _Lembus
+verminus_ (Müller) as described by Kent (_Proboscella vermina_), and
+_L. intermedius_ as described by Gourret & Roeser (_Lembus verminus_
+syn.)in the absence of annular markings and in the presence of a
+caudal bristle. It differs from the former, however, in the absence
+of a tentacle-like process, and from both in the absence of a double
+nucleus and in the presence of many vacuoles. These features are so
+characteristic of all the specimens examined that I have concluded,
+somewhat reluctantly, to give it a specific name. It is common in old
+infusions of algæ, especially after decomposition is well advanced.
+Its food consists of bacteria.
+
+
+[Illustration: Fig. 42.--_Lembus infusionum_.]
+
+
+Lembus pusillus Quennerstedt 1869.  Fig. 43.
+
+Synonym: _L. subulatus_ Kent 81.
+
+This species is much smaller than the preceding, and might easily
+be mistaken for _Uronema marina_. It is subcylindrical in form, the
+anterior end bluntly pointed, the posterior end rounded. The oral
+apparatus is quite different from _Uronema_. The mouth, as in the
+preceding species, is at the end of a long peristomial groove
+extending from the anterior end to the middle of the body. The edges
+of the peristome bear undulating membranes as in _L. infusionum_.
+Like the latter, there is one caudal bristle, but unlike it there is
+only one posterior contractile vacuole, while the endoplasm is filled
+with large granules or food balls. The cuticle is distinctly striated
+with longitudinal markings, and the cilia are uniform in length.
+
+Habitat similar to that of _L. infusionum_, in zoogloea masses.
+Length 26 to 30µ; diameter 7 to 8µ.
+
+Although Quennerstedt's description of _L. pusillus_ makes no mention
+of a caudal bristle, the size and other characters are so closely
+similar that I hesitate to make a new species. The bristle is
+extremely delicate, scarcely thicker than a cilium, and easily
+overlooked, yet with proper focussing of the condenser I found it on
+every specimen examined.
+
+
+[Illustration: Fig. 43.--_Lembus pusillus_.]
+
+
+KEY TO MARINE GENERA OF OPALINIDÆ.
+
+Diagnostic characters: The form is oval, and the body may be short or
+drawn out to resemble a worm. They are characterized mainly by the
+absence of mouth and pharynx.
+
+Anterior end not pointed; body            Genus *_Anoplophrya_
+cylindrical; tapering
+
+Anterior end pointed; body elongate;      Genus _Opalinopsis_
+cylindrical; tapering
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus ANOPLOPHRYA Stein '60.
+
+(Stein '60; Claparède '60; Leidy '77; Vejdovsky '79; Kent '81;
+Balbiani '85; Bütschli '88; Shevyakov '96.)
+
+The general form is elongate, cylindrical or slightly flattened, with
+rounded ends, the posterior end tapering. The body is striated with
+clearly defined, often depressed lines, which run longitudinally and
+sometimes spirally. The contractile vacuoles are usually placed in
+rows upon the edges. The macronucleus is almost always long and
+band-formed, rarely oval, and generally extending through the entire
+length of the body. Micronuclei have been made out in one case.
+Reproduction is effected by simple cross division or by budding at
+the posterior end, and is frequently combined with chain formation.
+The main characteristic is the entire absence of mouth and
+oesophagus, the animals being parasitic in the digestive tract of
+various annelids. Parasites, salt-water forms.
+
+
+Anoplophrya branchiarum. Stein '52.  Fig. 44.
+
+_A. circulans_ Balbiani.
+
+The body is cylindrical to pyriform, in the latter case broadened
+anteriorly. Cuticle distinctly marked by longitudinal striations
+which take the form of depressions and give to the body a
+characteristic melon shape. The endoplasm contains a number of large
+refringent granules--probably body products. The nucleus is elongate,
+somewhat curved, and coarsely granular. A micronucleus lies in the
+concavity. The cilia are long, inserted rather widely apart along
+the longitudinal markings. The contractile vacuole is single and
+is located at the pointed end, which is directed backwards during
+locomotion. One specimen found free swimming among some algæ.
+
+Length 104µ; greatest diameter 36µ.
+
+I was much surprised to find this form swimming about freely in the
+water; its mouthless condition showed it to belong to the family of
+parasites, the _Opalinidæ_. As the name indicates, however, this
+species is an ectoparasite upon the gills, and Stein gave the name
+_branchiarum_ to a fresh-water form parasitic upon _Gammarus pulex_.
+The Woods Hole form is so strikingly similar to the figure of _G.
+branchiarum_ that, although the name was given to a fresh-water form,
+it obviously applies to this marine variety. One important difference
+is the presence of only one contractile vacuole in the marine form.
+
+
+[Illustration: Fig. 44.--_Anoplophrya branchiarum_.]
+
+
+KEY TO FAMILIES OF HETEROTRICHIDA.
+
+Cilia cover the body                      1
+
+Cilia reduced to certain                  2
+localized areas
+
+1. _Polytrichina_.
+
+   a. The mouth terminates a long         Family _Plagiotomidæ_
+      peristomial furrow having an
+      adoral zone along the entire
+      left edge
+
+   b. Peristomial area a broad            Family _Bursaridæ_
+      triangular area ending in mouth
+
+   c. Peristomial depression short;       Family _Stentoridæ_
+      limited to the anterior end; its
+      plane at right angles to the
+      long axis of body; surface of
+      peristome striated and ciliated;
+      no undulating membranes
+
+2. _Oligotrichina_.
+
+   a. Peristome without cilia; cilia      Family _Halteriidæ_
+      limited to one or more girdles
+      about body
+
+      One marine genus                    *_Strombidium_
+
+   b. Thecate forms; the body is          Family _Tintinnidæ_
+      attached by a stalk to the cup;
+      within the adoral zone is a ring
+      of cilia.
+
+   c. The peristomial depression is       Family _Ophryoscolecidæ_
+      deep and funnel-like; cuticle
+      thick, with posterior spine-like
+      processes.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO THE MARINE GENERA OF PLAGIOTOMIDÆ.
+
+Diagnostic characters: The peristome is a narrow furrow which begins,
+as a rule, close to the anterior end and runs backward along the
+ventral side, to the mouth, which is usually placed between the
+middle of the body and the posterior end. A well-developed adoral
+zone stretches along the left side of the peristome, and is usually
+straight.
+
+1. Body cylindrical; size medium;         Genus _Metopus_
+   peristome long and turns sharply
+   to the left at the extremity
+
+2. No torsion in the peristome;           Genus _Blepharisma_
+   undulating membrane is confined
+   to the posterior part of peristome
+
+3. No peristomial torsion;                Genus _Spirostomum_
+   body highly contractile;
+   no undulating membrane
+
+
+KEY TO THE MARINE GENERA OF BURSARIDÆ.
+
+Diagnostic characters: The body is usually short and pocket-like, but
+may be elongate. The chief characteristic is the peristome, which is
+not a furrow, but a broad triangular area deeply insunk and ending in
+a point at the mouth. The adoral zone is usually confined to the left
+peristome edge, or it may cross over to the right anterior edge.
+
+1. The anterior half of the body          Genus _Balantidium_
+   tapers to nearly a point in front;
+   the peristome is narrowest at the
+   apex; the mouth is the entire
+   peristome base.
+
+2. The anterior end does not taper;       Genus *_Condylostoma_
+   the peristome is widest at the end
+   of the body; the mouth is clearly
+   defined.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus CONDYLOSTOMA (KONDYLOSTOMA Bory de St. Vincent 1824) Dujardin
+'41
+
+(Dujardin '41; Claparède & Lachmann '58; Stein '59, '67; Cohn '66;
+Quennerstedt '67; Wrzesniowski '70; Bütschli '76, '88; Kent '81;
+Maupas '83; Shevyakov '96.)
+
+Colorless and more or less flexible animals of medium size. The
+general form is elongate and cylindrical or somewhat smaller
+anteriorly. The posterior end is broadly rounded, the anterior end
+somewhat truncate and oblique. The peristome is broad and triangular,
+the base of the triangle being the entire anterior end of the body.
+The entire length of the peristome is one-fourth or less of the body
+length. The mouth is large and placed at the apex of the peristomial
+triangle and opens into a comparatively small oesophagus. The right
+edge of the peristome is lamellate and bears a clearly defined
+undulating membrane. The adoral zone is well developed upon the left
+edge of the peristome, from which it passes around anteriorly to the
+right edge. The surface of the peristome is free from cilia, but
+the rest of the body is uniformly coated with small active cilia.
+Contractile vacuoles are not safely determined. Bütschli thinks
+there is probably one terminal vacuole, but some observers deny this
+(_e.g._ Maupas). Others describe them on the dorsal side of the
+posterior end (Quennerstedt). The macronucleus is long and beaded and
+placed upon the right side. Micronuclei are numerous and scattered
+along the macronucleus. The anus is terminal and dorsal. Food
+consists of large and small particles. Movement rapid, free swimming,
+alternating with resting periods; in some cases an undulating or
+wriggling movement is seen, showing clearly the flexibility of the
+body. Fresh and salt water.
+
+
+Condylostoma patens Müller.  Fig. 45.
+
+The body is elongate, somewhat sac-like, five or six times as long
+as broad, plastic, and frequently contains brightly colored food
+granules. The triangular peristome takes up the greater part of the
+anterior end, and the mouth is situated at the sharper angle of the
+triangle, about one-fourth of the total length from the anterior end.
+The cuticle is longitudinally striated, the lines having a slightly
+spiral course. They are not closely set, and fine cilia are thickly
+inserted along their edges. The endoplasm is granular and viscous.
+The motile organs consist of an adoral zone of membranelles, which
+stretch along the left edge of the peristome and the front edge of
+the body. The right edge of the peristome supports an undulating
+membrane. The nucleus is moniliform and extends the full length of
+the left side; a number of micronuclei are distributed along its
+course (Maupas).
+
+Length 400µ; diameter at widest part 105µ. Maupas gives the length
+from 305µ to 495µ; and Stein 376µ to 564µ. Very common.
+
+For a more extended account of the structures, see the excellent
+description by Maupas '83.
+
+
+[Illustration: Fig. 45.--_Condylostoma patens_.]
+
+
+KEY TO THE MARINE GENERA OF STENTORIDÆ.
+
+Diagnostic characters: The peristome is relatively short and limited
+to the front end of the animal, so that its plane is nearly at right
+angles to that of the longitudinal axis of the body. The adoral zone
+of cilia either passes entirely around the peristome edge or ends at
+the right-hand edge. The surface of the peristome is spirally
+striated and provided with cilia. Undulating membranes are absent.
+
+1. Peristome circular in outline;         Genus _Stentor_
+   limited to the anterior end
+
+2. The peristome is drawn out into two    Genus _Folliculina_
+   wing-like processes; tube-dwelling
+
+
+Genus STROMBIDIUM Cl. & Lach. '58.
+
+(Stein '67; Bütschli '73; Fromentel '74; Kent '81; Gruber '84; Entz
+'84; Maupas '83. Bütschli '88.)
+
+Small, colorless (except for ingested food) animals with
+characteristic springing movements. The form is usually constant, but
+in some cases may be plastic like _Astasia_; it is usually globular
+or conical, the posterior end being more or less pointed, the
+anterior end broadest. The latter is surrounded by a complete circle
+of the adoral zone, the oral end of which passes into a peristomial
+depression which extends deep into the middle of the body. The mouth,
+with a very small oesophagus, lies at the bottom of the inturned
+peristome. The region surrounded by the adoral zone is frequently
+drawn out into an anterior process, occasionally bearing a pigment
+mass. The ventral surface in some cases bears cilia, which may be
+distributed or restricted to a row of large cilia. Trichocysts are
+usually present and may be widely spread, limited to the posterior
+region, or arranged in a girdle about the middle. The contractile
+vacuole is simple, and posterior in position. The macronucleus
+is spherical and usually central in position. Movement is rapid
+swimming, combined with resting and floating periods, the latter
+usually terminated by a sudden leap.
+
+Fresh and salt water; more common in the latter.
+
+
+Strombidium caudatum Fromentel '74.  Fig. 46, a, b, c.
+
+Fromentel described a fresh-water form of this genus with a caudal
+appendage. The body is pyriform, broadly truncate on the anterior
+end, in the middle of which rises a papilliform process (Schnabel).
+On this process is a heap of pigment granules, which, however, are
+not constant. A ring of long cirri surround the anterior end and pass
+into the peristome, and from the left edge of this line of cirri a
+large adoral zone continues down to the mouth. The peristome is
+elongate and sac-form, and the mouth lies at the posterior extremity.
+With the exception of a caudal filament there are no other motile
+organs; this is about half as long as the body, structureless,
+hyaline, and sharply pointed. It splits up into a bundle of fine
+fibers upon treatment with caustic potash (c). The cirri emerge from
+minute hollows in the edge of the anterior border. The cortical
+plasm contains peculiar rod-like bodies, which look more like lines
+or markings than like rods or trichocysts. The nucleus is large,
+spherical, and placed in the center of the body. The contractile
+vacuole is posterior.
+
+Length without appendage is about 35µ; greatest diameter 15 to 18µ.
+In decaying vegetable matter. Common.
+
+
+[Illustration: Fig. 46.--_Strombidium caudatum_.]
+
+
+Although Fromentel's species is incompletely described, it is very
+evident that the organism corresponds fairly well with the Woods Hole
+variety. His was a fresh-water type; this is marine, but the caudal
+filament and the contractile vacuole are similar. Certainly in this
+case the organism can not be regarded as a Vorticella broken off its
+stalk, as Kent '81 suspected. The anterior process with its pigment
+spot; the cirri, the spherical nucleus, the position of the vacuole,
+etc., are all opposed to such an interpretation which Kent applied to
+the original species. Neither can it be a Tintinnoid. I place it
+provisionally as _S. caudatum_.
+
+
+KEY TO THE MARINE GENERA OF TINTINNIDÆ.
+
+Diagnostic characters: Body attached by a stalk to a cup. Inside the
+zone of membranelles is a ring of cilia (par-oral).
+
+1. The test is gelatinous and more or     Genus _Tintinnidium_
+   less covered by foreign particles
+
+2. The test is chitinous and clear.       Genus _Tintinnus_
+   No foreign particles.
+
+3. The test is chitinous; covered by      Genus *_Tintinnopsis_
+   foreign particles, growth rings
+   frequent
+
+4. The test is chitinous, often           Genus _Codonella_
+   covered by foreign particles.
+   The test is marked by discoid,
+   circular, or hexagonal spots.
+
+5. The test is perforated by pores        Genus _Dictyocysta_
+   of circular or hexagonal form.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus TINTINNOPSIS Stein '67.
+
+(Stein '67; Kent '81; Daday '87; Bütschli '88.)
+
+Medium-sized ciliates, inclosed in a chitinous lorica with embedded
+sand crystals. The form of the house, or lorica, varies greatly.
+In some cases the mouth opening is wide, giving the lorica a bell
+form; it may be long and tubular, short and spherical, or variously
+indented. The animal is attached, as in the closely allied genus
+_Tintinnus_, by a peduncle to the bottom of the lorica. The anterior
+end of the animal is inclosed by two complete circles of cilia;
+one, the outer, forming the adoral zone, is composed of thick
+tentacle-like membranelles, the other consists of shorter cilia
+within the adoral zone. The mouth leads into a curved oesophagus
+containing rows of downward-directed cilia (Daday). The entire body
+is covered with cilia, but as the lorica is always opaque these can
+be made out only when the animal is induced to leave the house. The
+only difference between this genus and _Tintinnus_ is the covering
+of foreign bodies--usually sand crystals. Movement is rapid and
+restless, and peculiarly vibratory, owing to the apparent awkwardness
+in moving the house.  Salt water.
+
+
+Tintinnopsis beroidea Stein, var. plagiostoma Daday.  Fig. 47.
+
+Synonym: _Codonella beroidea_ Entz '84.
+
+The shell is colorless, thimble-shaped, with a broadly rounded
+posterior end. The body is cylindrical. The internal organs were not
+observed. Membranelles 24 in number. Length 50µ; greatest diameter
+40µ.
+
+
+[Illustration: Fig. 47.--_Tintinnopsis beroidea_.]
+
+
+Var. compressa Daday '87.
+
+The posterior end of the shell is pointed, the lower third of the
+shell is swollen, the upper third is uniform in diameter and without
+oral inflation or depression. Nucleus not seen.
+
+Length 70µ; greatest diameter 48µ.
+
+
+Tintinnopsis davidoffi Daday.  Fig. 48.
+
+The shell is large, elongated, and provided with a considerable
+spine. The chitin of the shell is covered with silicious particles of
+diverse size. The internal structures were not observed.
+
+Length of shell and spine 230µ; diameter of the oral aperture 54µ.
+
+
+[Illustration: Fig. 48.--_Tintinnopsis davidoffi_.]
+
+
+The variations of these species are considerable, and as the internal
+structures, such as the nucleus, are essential in fixing their
+systematic position, I place them as above, provisionally, and until
+further observations can be made.
+
+
+KEY TO FAMILIES OF HYPOTRICHIDA.
+
+a. Peristome indistinct; cilia on         Family _Peritromidæ_
+   ventral surface uniform and not        One genus, *_Peritromus_
+   differentiated into cirri
+
+b. Peristome more or less indistinct;     Family _Oxytrichidæ_
+   cilia reduced to a few rows on the
+   ventral surface; anal and frontal
+   cirri present
+
+c. Cilia entirely reduced; frontal        Family _Euplotidæ_
+   and anal cirri present or reduced;
+   macronucleus band-formed or spherical
+
+d. Peristome reduced to left edge and     Family _Aspidiscidæ_
+   does not reach over the anterior       One genus, *_Aspidisca_
+   margin
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PERITROMUS Stein '62.
+
+(Stein '62, '67; Maupas '83.)
+
+The body is flat, colorless or tinged with yellow, and contractile.
+It is elliptical in outline, with broadly rounded ends; in some
+cases the left edge is slightly incurved, the right edge convex.
+The ventral surface is flat, the dorsal surface is arched in the
+middle region of the body. The edges being flat are somewhat more
+transparent than the remainder of the body. The ventral surface is
+striated by longitudinal straight or slightly curved lines, the
+dorsal surface is smooth and without cilia. (Maupas describes
+bristles on the back, but this is not corroborated.) The adoral zone
+is fairly well developed, but not distinctly marked off from the
+remaining ventral surface. It begins on the right side and extends
+entirely around the frontal margin and down the left side below the
+middle of the body, where it turns suddenly to the right, entering
+the slightly insunk peristome. The mouth leads into a short,
+indistinct oesophagus. One contractile vacuole is situated in the
+dorsal swelling at the posterior end of the animal. Macronucleus
+double, one in each side of the dorsal swelling. Movement is slow
+and creeping, with a peculiar method of contracting the more hyaline
+edge, which may turn upward or around a foreign object.
+
+Fresh (?) and salt water.
+
+
+Peritromus emmæ Stein.  Fig. 49.
+
+With the characters of the genus.
+
+
+[Illustration: Fig. 49.--_Peritromus emmæ_, ventral and lateral
+aspects.]
+
+
+KEY TO THE MARINE GENERA OF OXYTRICHIDÆ.
+
+Diagnostic characters: The peristome is not always marked off from
+the frontal area. In the most primitive forms the cilia on the
+ventral surface are similar to those of the preceding family
+(_Peritromidæ_). Usually some of the anterior and some of the
+posterior cilia are fused into cirri, distinguished as the frontal
+and anal cirri, respectively. In the majority of forms all of the
+cilia are thus differentiated; strong marginal cirri are formed in
+perfect rows, and ventral cirri in imperfect rows. In addition to the
+adoral zone there is an undulating membrane on the right side of the
+peristome, and in some cases a row of cilia between the membrane
+and the adoral zone. These are the par-oral cilia and they form the
+par-oral zone.
+
+1. The posterior end is pointed or        2
+   tail-like
+
+   The posterior end is rounded;          5
+   not tail-like
+
+2. The front end is pointed               3
+
+   The front end is rounded               4
+
+3. Frontal and anal cirri absent;         Genus _Stichotricha_
+   often tube-forming
+
+   Eight frontal and 3 caudal cirri;      Genus _Gonostomum_
+   not tubiculous
+
+4. Anal cirri present; with or            Genus *_Epiclintes_
+   without short lateral bristles
+
+   Anal cirri absent; no bristles         Genus _Uroleptus_
+
+5. With frontal cirri                     6
+
+   No frontal cirri; 2 to 3 rows of       Genus _Holosticha_
+   ventral cirri; anal cirri small
+
+6. Right margin of peristome straight     Genus _Oxytricha_
+   as far as the anterior end; 5 rows
+   ventral cirri; 5 anal cirri
+
+   Right margin of peristome curved       7
+
+7. Five rows or less of ventral cirri     8
+
+   More than 5 rows of ventral cirri      Genus _Urostyla_
+
+8. Membranelles normal; 5-10 anal         Genus *_Amphisia_
+   cirri; no caudal cirri
+
+   Membranelles normal; 5 to 10 anal      Genus _Stylonychia_
+   cirri; 3 caudal cirri
+
+   Membranelles very large and            Genus _Actinotricha_
+   powerful; adoral zone not
+   continued to mouth; 5 anal cirri
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EPICLINTES Stein '62.
+
+(Stein '62, '64, '67; Mereschowsky '79; Gruber '87; Bütschli '88.)
+
+Very active, contractile, colorless forms of rather small size. In
+the fully expanded condition the body is oval and long, with its
+greatest width in the center or at the front half of the body. The
+posterior end is always drawn out into a relatively long tail, which
+is extremely elastic. The peristome is short and stretches around the
+front end of the animal. In the frontal region are from one to three
+rows of cirri. The ventral surface is covered with longitudinal rows
+of cilia, the number of rows being in dispute (6 to 7 according to
+Stein; 9 according to Mereschowsky and Rees) Some of these cilia
+project from the lateral edges and from the posterior end, where
+they are slightly elongated. The anus is dorsal and placed at the
+beginning of the posterior process. Macronucleus probably double.
+Movement is rapid and restless, the tail process contracting to jerk
+the body backward. Salt water.
+
+
+Epiclintes radiosa Quenn.  Fig. 50.
+
+Synonym: _Metra radiosa_ Quenn.
+
+The body is elongate, slightly narrowed anteriorly, and drawn out
+posteriorly into a long, retractile, tail-like portion. Five large
+cirri extend outward from the anterior extremity. The caudal portion
+may be extended to a distance equal to twice the length of the body
+or contracted to half the length. The peculiar nervousness of this
+form made it extremely difficult to study, and the oral region was
+imperfectly made out. The anterior cirri appear to line the upper
+left border of the peristome, which is marked by a row of large
+cilia. The peristome begins upon the right side of the anterior end
+and passes backward and to the left, narrowing at this point. The
+mouth is very small and difficult to see. It is apt to stay in
+one locality under zoogloea, switching back and forth with great
+vivacity, or hanging on by the posterior cilia while the anterior
+end stretches out in the surrounding medium. Nucleus and contractile
+vacuole were not observed. Length 45µ.
+
+
+[Illustration: Fig. 50.--_Epiclintes radiosa_.]
+
+
+Genus AMPHISIA Sterki '78.
+
+(Sterki '78; Kent '81; Bütschli '88.)
+
+The body is plastic and soft, colorless or slightly tinged with
+yellow or red. In form it is oval or elongate, the posterior end
+is rounded and slightly reduced in diameter, but does not form a
+distinct tail. The anterior end is also rounded and similarly reduced
+in width. There are two rows of marginal cirri (_Randcirren_), which
+may be placed some distance from the edge, and two or three rows of
+ventral cirri between them. There are from 3 to 5 frontal cirri of
+larger size than those of the ventral rows, and from 5 to 10 anal
+cirri. (The genus _Holosticha_ is similar in all respects save
+the presence of frontal cirri.) The macronucleus is double; the
+contractile vacuole is central and on the left side. The peristome
+is long and rather narrow and carries an undulating membrane on its
+right margin. Fresh and salt water.
+
+
+Amphisia kessleri Wrzes. '77.  Fig. 51.
+
+Synonyms: _Trichoda gibba_ Müller; _Oxytricha gibba_ Stein '59; _O.
+velox?_ Quen. '69; _O. kessleri_ Wrzes. '77.
+
+Body elongate, slightly sigmoid and swollen in the center, about
+3-1/2 times as long as broad; the rounded anterior end is turned to
+the left, the similarly rounded posterior end to the right; both ends
+taper slightly. The peristome is long and narrow, with a distinct
+adoral zone which appears broken in its course. To the right of this
+adoral zone is a single line of preoral cilia. On the right border of
+the peristome is an undulating membrane. The three frontal cirri form
+a triangle and the five smaller anal cirri form a continuous line
+with the broken row of ventral cirri. There are two and one-half rows
+of ventral cirri and the marginal cirri are drawn in until they are
+ventral in position.
+
+Length 135µ; greatest width 40µ.
+
+
+[Illustration: Fig. 51.--_Amphisia kessleri_.]
+
+
+This variety differs from _O. kessleri_ as described by Wrzesniowski
+in having three frontal cirri instead of four. Another difference
+is in the structure of the nuclei and in their position. These
+differences are too minute to warrant a specific name. _O. velox_ of
+Quennerstedt is probably the same as _0. kessleri_, but differs in
+having three complete rows of ventral cirri. _O. velox_ has three
+frontal cirri in a line, thus differing from the Woods Hole form.
+
+
+KEY TO THE MARINE GENERA OF EUPLOTIDÆ.
+
+Diagnostic characters: Cilia, as well as the frontal, marginal, and
+ventral cirri, very much reduced; the anal cirri, on the other hand,
+are always present. The macronucleus is band-form.
+
+1. Frontal cirri more than 8              2
+
+   Frontal cirri less than 8              3
+
+2. Eleven marginal cirri on the left      Genus _Certesia_
+   side; 11 frontal cirri
+
+   Four marginal cirri, 2 on each         Genus *_Euplotes_
+   side; 9 to 10 frontal cirri
+
+3. Seven frontal, 5 anal, 3 right         Genus *_Diophrys_
+   marginal, and 2 left marginal
+   cirri
+
+   No frontal, 5 anal, 3 right,           Genus *_Uronychia_
+   and 2 left marginal cirri
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EUPLOTES (Ehr. 1831) Stein '59.
+
+(Ehrenberg '31, '38; Stein '59; Cl. & Lach. '58; Quennerstedt '65,
+'67, '69;  Bütschli '88; Kent '81; Gourret & Roeser '88; Möbius '88.)
+
+Small to medium-sized forms. Rigid in form, colorless, or green by
+chlorophyl. They are quite flat on the ventral surface but decidedly
+arched dorsally, and the contour is usually oval. The anterior end is
+broadly rounded to truncate; the posterior end is similarly rounded,
+or may be somewhat pointed. The mouth is placed centrally or near
+the left margin, and from it the right edge of the peristome forms a
+curved line to the left, which bends forward, thus making the greater
+part of the left edge the peristomial area. In front the peristome
+bends sharply to the right and extends as far as the right end of the
+adoral zone. Upon the frontal and median ventral surface are 9 to 10
+great cirri (_Bauchwimpern_ of Stein). Posteriorly five great anal
+cirri stretch out beyond the posterior body margin. In addition to
+these there are two smaller marginal cirri upon the left body edge,
+and two similar ones on the hinder part of the body. The dorsal
+surface is rarely smooth, but usually is marked by longitudinal
+ridges, and rows of dorsal bristles have been described. The single
+contractile vacuole lies on the right side in the region of the
+anal cirri, sometimes just above them, sometimes below. The anus is
+posterior and on the right side. The characteristic macronucleus is
+long and band-form, its main portion being usually on the left side
+with an anterior and a posterior arm toward the right. Movement is
+rapid swimming, which, however, is frequently broken by creeping
+periods, during which the animals appear to be examining the foreign
+body on which they creep.
+
+Fresh and salt water.
+
+
+Euplotes charon Ehr.  Fig. 52.
+
+Synonyms: _Trichoda charon_ Müller; _Ploesconia charon_; _P.
+affinis_, _subrotunda_, _radiosa_, _longiremis_, Dujardin '41.
+
+The body is oval, small, and somewhat variable in length. The
+carapace is strongly marked upon the dorsal side by deep longitudinal
+grooves, 6 to 8 in number; the grooves may be absent, however. The
+adoral zone extends to the posterior third of the body, the mouth
+and oesophagus are directed anteriorly. There are 10 ventral cirri,
+7 of which are on or near the frontal border and 3 near the right
+edge. There are 5 posterior cirri and 4 anal cirri, of much smaller
+size. The cirri may or may not be fimbriated, the latter condition
+indicating the approaching disintegration of the body and is
+abnormal. The macronucleus is long and band-formed or horseshoe
+shape. The contractile vacuole lies on the right side dorsal to the
+posterior cirri.
+
+Fresh and salt water. Length 45µ; diameter 25µ.
+
+
+[Illustration: Fig. 52.--_Euplotes charon_, dorsal and ventral
+aspects.]
+
+
+Euplotes harpa Stein.  Fig. 53.
+
+The body is elongate, oval, somewhat widened anteriorly, and has
+rounded ends. The frontal margin is three-toothed. Ten ventral cirri.
+Dorsal surface provided with 8 longitudinal markings. The peristome
+is long and broad, with considerable variation. The adoral zone
+consists of powerful membranelles arranged in a continuous curve
+from the mouth to the extreme right frontal margin. Seven of the 10
+ventral cirri are situated at the anterior extremity; the remainder
+are arranged in a triangle on the right edge. The anal cirri, 5 in
+number, are long and stiff; the marginal cirri smaller and finer. The
+nucleus and contractile vacuole are similar to those of the preceding
+species.
+
+Length 95µ; width 54µ.
+
+
+[Illustration: Fig. 53.--_Euplotes harpa_.]
+
+
+Genus DIOPHRYS Dujardin '41.
+
+(Bütschli '88.)
+
+Medium size, colorless to yellow, rigid in form. The body contour
+is oval, the anterior end being rounded or slightly reduced, the
+posterior end usually cut in on the right side. The peristome is
+broad but less extensive than in _Euplotes_, and may extend beyond
+the middle of the body. Its right edge is convex toward the right
+side, extends forward and does not turn again to the right. The
+anterior ventral surface has 7 to 8 scattered cirri and just behind
+the mouth is a transverse row of large anal cirri. In the sharp
+in-cut of the posterior end are three great angular cirri. Two
+lateral cirri are placed on the left of the median line between
+the mouth and the anal cirri, and usually in a slight hollow. The
+contractile vacuole is on the right side in the vicinity of the
+anal cirri. The macronucleus is in two parts, each band-form, one
+anterior, the other posterior in position. Movement is rapid and
+steady. Salt water.
+
+
+Diophrys (Styloplotes) appendiculatus Stein '59.  Fig. 54.
+
+Synonyms: _Styloplotes appendiculatus_ Stein '59; Kent '81;
+Quennerstedt '67, etc.
+
+The general form resembles _Euplotes_. Its outline is oval and
+regular except at the posterior end on the right side, where there is
+a considerable indentation. The frontal margin is characterized by a
+row of powerful membranelles, which become smaller at the peristome
+and at the mouth they are of characteristically small size. The
+ventral cirri are 7 in number. Five of them are in one row from the
+anterior end down the right side nearly to the anal cirri; 1 is on
+the frontal border between the first two; 1 lies just anterior to the
+second anal cirrus from the right side. The 5 anal cirri are large
+and powerful and extend some distance beyond the posterior end of the
+body. In all specimens observed these cirri curve to the left. Dorsal
+to the anal cirri and placed deep into the dorsal pit are 3 large,
+sharply curved cirri, which in most cases are fimbriated, but when
+the specimens are normal these are pointed and curve abruptly to the
+right. Two smaller cirri lie to the left of the group of anal cirri.
+The peristome is well-marked by the adoral zone, and upon its right
+border there is a row of cilia, and a similar row of cilia runs along
+the base of the oral membranelle. The macronucleus is double and
+consists of two elongate cylindrical masses lying parallel with
+one another. One of these is in the anterior region; the other is
+posterior. The contractile vacuole lies dorsal to the anal cirri
+and anterior to the three dorsal cirri. The movement and general
+activities resemble those of _Euplotes_.
+
+Length 50µ; diameter 25µ.
+
+
+[Illustration: Fig. 54.--_Diophrys appendiculatus_.]
+
+
+Genus URONYCHIA Stein '52.
+
+(Stein '59, '67; Quennerstedt '67; Kent '81; Bütschli '88.)
+
+Medium-sized colorless ciliates of usually constant body form. The
+body is somewhat short and oval in outline. The anterior end is
+broadly truncate, the posterior end rounded or slightly pointed. The
+ventral and dorsal surfaces are considerably arched and the latter
+usually has a number of rows of longitudinal stripes. The open
+peristome is broad and reaches back to the middle of the ventral
+surface and beyond. According to Stein, the two edges can approach
+each other, thus opening and closing the peristomial area. Its right
+edge forms a greater angle with the front edge than in the genus
+_Euplotes_, and the left edge forms a greater angle with the front
+edge than in that genus. The left edge also appears to cover over the
+adoral zone slightly. There are no ventral cirri in front, but on the
+posterior ventral surface are 7 great springing cirri. Five of these
+are inserted on the right aide in a deep in-sinking, and the other 2
+in a similar depression on the left ventral surface. Above the 5
+right-side cirri, _i.e._, dorsal to them, but in the same depression,
+are 3 angular cirri. A few edge cirri are found to the left of them
+and another to the right of the 5 cirri. The contractile vacuole is
+on the left side between the main groups of cirri. The macronucleus
+is band-form or spherical, and is situated in the middle region of
+the body. Movement consists in forward swimming with sudden springs.
+
+Salt water.
+
+
+Uronychia setigera, n. sp.  Fig. 55.
+
+This species is very common in the Woods Hole waters. It is small,
+colorless, and very active. The most characteristic feature is
+the posterior end with its relatively enormous cirri, which are
+apparently large enough for an animal four times its size. The form
+is ovoid, widened posteriorly.
+
+The ventral surface is flat and has two excavations in the posterior
+end. The right hollow is larger and contains 5 great cirri of unequal
+size, the extreme right one being the largest. The left hollow
+contains 2 cirri, also of dissimilar size. Dorsal to the 5 right
+cirri are 3 sickle-formed cirri, which are usually fimbriated. These
+are pointed and curve regularly to the left. The peristome is wide
+and open, and a small pocket-like hollow on its left border indicates
+the region of the mouth. The adoral zone runs into this pocket
+and the mouth is located in its lower right-hand corner. In _U.
+transfuga_ the right border is generally described as having a
+membrane of extreme delicacy. I was unable to see such a membrane in
+this form, but in its place there are 2 flagella-like cirri extending
+from the margin of the mouth-opening into the peristome, and these
+vibrate slowly. I do not believe these could be the moving edge of an
+undulating membrane, for they are quite distinct. The macronucleus is
+spherical instead of band-form, and a single micronucleus is closely
+attached. This is unlike the European species _U. transfuga_, in
+which the nucleus is elongate. The contractile vacuole lies between
+the two sets of posterior cirri. There are no marginal folds like
+those of the European species.
+
+Length 40µ; width 25µ. Common.
+
+
+[Illustration: Fig. 55.--_Uronychia setigera_.]
+
+
+Genus ASPIDISCA Ehr. 1830.
+
+(Perty '52; Cl & Lach. '58; Stein '59; Quennerstedt '65, '67, '69;
+Mereschowsky '79; Kent '81; Bütschli '88.)
+
+Small, colorless, and rigid forms, with nearly circular to oval
+contour. The left side is usually straight, or at least but slightly
+convex. The right side is much more convex, and the right margin is
+considerably thickened. The ventral side is flat, the dorsal surface
+convex, with from one to several longitudinal ridges which run more
+or less parallel with the right edge. The peristome is limited to the
+left edge, where it forms a small depression which may or may not
+reach the anterior border, but which in no case runs around the
+anterior margin. The left peristome margin in some cases grows
+over the peristome depression toward the right, thus making a sort
+of cover for the peristome. In the posterior region is a deep
+depression, from which 5 to 12 cirri take their origin. Seven or 8
+cirri are placed in the anterior half of the ventral surface and
+are arranged more or less in rows. The anus is on the right side in
+the region of the anal cirri (Stein). The contractile vacuole is
+generally on the right side and similarly located. The macronucleus
+is a horseshoe-shaped body. Movement rapid, somewhat in circles, and
+rather uniform.
+
+Fresh and salt water.
+
+
+Aspidisca hexeris Quennerstedt '67.  Fig. 56.
+
+The carapace is elliptical, about 1-1/2 times as long as broad,
+rounded at the extremities. The left border of the carapace bears a
+spur-like projection. The ventral cirri are short and thick, and are
+very characteristic of the species. When moving slowly they look much
+like nicely-pointed paint brushes, but when the animal is compressed
+they quickly become fibrillated, and then look like extremely old and
+worn brushes. These cirri are placed in depressions in the ventral
+surface and each one appears to come from a specific shoulder. At the
+posterior end an oblique hollow bears 6 unequal cirri placed side
+by side. The extreme right cirrus is the largest, and they become
+progressively smaller to the opposite end. Dorsal to these lies the
+contractile vacuole. The peristome is in the posterior half of the
+body and an undulating membrane extends from it into the oesophagus.
+The dorsal surface is longitudinally striated by 5 or 6 lines, which
+are usually curved. The nucleus is horseshoe-shaped and lies in the
+posterior half of the body. Length 68µ; diameter 48µ.
+
+
+[Illustration: Fig. 56.--_Aspidisca hexeris_.]
+
+
+This form was incorrectly mentioned as _Mesodinium_ sp. by Peck '95:
+
+In the figure given by Quennerstedt there are only 7 ventral cirri.
+In the Woods Hole form there are 8, 7 of which are anterior, 6 of
+them about one central one. The eighth cirrus is by itself, near the
+base of the largest posterior cirrus. These cirri, in spite of their
+size, are easily overlooked and more easily confused, but by using
+methylene blue they can be seen and counted.
+
+
+Aspidisca polystyla Stein.  Fig. 57.
+
+This species is similar to _A. hexeris_, but is smaller, very
+transparent, and without the spur-like process on the left edge of
+the carapace. The chief difference, however, lies in the number of
+anal cirri. These are 10 in number and they are arranged obliquely as
+in the preceding species, with the largest one on the right and the
+smallest on the left. The ventral cirri are 8 in number, and are
+arranged in two rows, one of which, the right, has 4 cirri closely
+arranged, the other having 3 cirri close together and one at some
+distance, near the largest anal cirrus. The peristome, contractile
+vacuole, and nucleus are similar to the preceding. Length 36µ; width
+22µ.
+
+
+[Illustration: Fig. 57.--_Aspidisca polystyla_.]
+
+
+Stein assigns only 7 ventral cirri to this species, but he also
+describes 2 very fine bristle like cilia (p. 125) and pictures them
+in figs. 18, 19, 20, and 21 of his Taf. III in the same relative
+position as my eighth cirrus. I am positive that cilia do not occur
+on the ventral face of this form, and that the characteristic cirri
+are the sole locomotor organs.
+
+
+KEY TO FAMILIES OF PERITRICHIDA.
+
+a. Peristome drawn out into               Family _Spirochonidæ_
+   funnel-like process; parasitic
+
+b. Adoral zone and circlet of cilia       Family _Lichnophoridæ_
+   at opposite end. Adoral zone           (one genus, *_Lichnophora_)
+   left-wound. Parasitic.
+
+c. Adoral zone a left-wound spiral.       Family _Vorticellidæ_
+   Attached or unattached forms.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LICHNOPHORA Claparède '67.
+
+(Gruber '84; Fabre-Domergue '88; Bütschli '88; Wallengren '94;
+Stevens 1901.)
+
+Small or medium-sized colorless animals, extremely elastic and
+flexible. The anterior part, bearing the adoral zone, is round or
+oval in ventral view, and has a flat ventral and a highly arched
+dorsal surface. The posterior end of the animal is reduced to a
+stalk-like structure which is broadened at the extremity to form
+a sucking disk. The surface of this disk and the surface of the
+peristome may be brought into the same plane by the characteristic
+bending of the stalk portion. A ciliated girdle is placed at the
+edge of the sucking disk. A well-developed adoral zone incloses the
+peristome; it begins at the mouth on the left side and includes
+nearly all of the peristome in its left-wound spiral, the extremity
+approaching closely the end near the mouth. The macronucleus is a
+long-beaded structure, or it may be in several parts connected by
+strands (Gruber). The contractile vacuole is on the left side in the
+region of the mouth. Salt water.
+
+
+Lichnophora macfarlandi Stevens.  Fig. 58.
+
+The body is elongate; oral disk variable in form, attachment disk
+clearly defined and constant. The stalk is very contractile and
+elastic, constantly changing in shape. When detached from the host
+the animal moves with a very irregular and indefinite motion. When
+attached it moves freely over the surface on its pedal disk. The
+latter is bordered by four membranes composed of cilia. A distinct
+axial fiber extends from the pedal disc to the peristome and gives
+off a number of branches. This fiber is analogous to the myonemes
+in _Vorticella_. An indistinct longitudinal furrow can be made out
+occasionally. The nucleus is in 5 or 6 separate pieces, of which 1
+is found in the pedal disk and 1 or 2 in the neck.
+
+On the egg capsules of _Crepidula plana_; also reported upon annelids
+at Woods Hole.
+
+Length 60µ from disk to extremity of the peristomial disk.
+
+
+[Illustration: Fig. 58.--_Lichnophora macfarlandi_.]
+
+
+This form does not agree in all respects with Stevens's species, but
+the agreement is so close in other respects that I believe it can be
+safely identified as _L. macfarlandi_. The mode of life is different,
+and the macronucleus is different, there being from 25 to 30
+fragments in Stevens's form and only 5 or 6 in the present one. There
+is, however, the same evidence of chain formation in both of them.
+The length of the oral cilia in  Stevens's form is 18µ in fixed and
+30µ in living forms. In the Woods Hole form the cilia are not more
+than half that length.
+
+
+KEY TO THE MARINE GENERA OF VORTICELLIDÆ.
+
+Diagnostic characters: Attached or unattached forma of peritrichous
+ciliates in which the adoral zone seen from above forms a right-wound
+spiral. A secondary circlet of cilia around the posterior end may be
+present either permanently or periodically.
+
+1. Posterior ciliated girdle              3
+   permanent around an attaching disk
+
+2. Posterior ciliated girdle,             4
+   temporary during motile stage
+
+3. Body cylindrical:
+
+  (a) With ring of stiff bristles         Genus _Cyclochæta_
+      above the ciliated girdle
+
+  (b) Without accessory ring of           Genus _Trichodina_
+      bristles; with velum
+
+         Body conical; general            Genus _Trichodinopsis_
+         surface ciliated
+
+4. No test and no stalk                   Genus _Scyphidia_
+
+5. No test; with stalk containing         8
+   contractile thread
+
+6. No test; with stalk but without        Genus _Epistylis_
+   contractile thread
+
+7. With a test; with or without           Genus *_Cothurnia_
+   a stalk
+
+8. Individuals solitary                   Genus *_Vorticella_
+
+   Individuals colonial;                  Genus *_Zoothamnium_
+   entire colony contractile
+
+   Individuals colonial; parts            Genus _Carchesium_
+   only of the colony contractile
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus VORTICELLA (Linnæus 1767) Ehr. '38
+
+(Bell Animalcule Leeuwenhoek 1675; Ehrenberg '38; Dujardin '41; Stein
+'51; Cl. & Lach. '58; Greeff '70; Bütschli '88; Kent '81; Stokes '88;
+etc.)
+
+Medium-sized ciliates of general bell-like form. They may be
+colorless, or yellow and green through the presence of Zoochlorella.
+When not contracted, the peristome end is widespread, rarely
+narrowed. The adoral zone and peristome agree with the details given
+in the family characteristics. The chief character is the attachment
+of the posterior end by means of a single, longer or shorter, stalk,
+which contains a highly contractile thread easily distinguished
+in the living animal. Another character is the absence of colony
+formation. Contractile vacuole, single or double, usually connected
+with a sac-like reservoir. The macronucleus is invariably long and
+band-formed, with attached micronucleus. Fresh and salt water.
+
+So many species of _Vorticella_ have been described that the task of
+collecting data and of arranging the synonyms is extremely irksome
+and difficult. Stokes enumerates 66 species, inhabiting fresh and
+salt water, and several other new species have been added since his
+work. I am impressed with the fact that new species have been created
+without proper regard for the manifold variations which nearly all
+of the _Ciliata_ show, and I believe the 66 species might be safely
+reduced to 12 or 15.
+
+
+Vorticella patellina Müller.  Fig. 59.
+
+Body campanulate, widest at anterior border, from which it tapers
+directly to the pedicle. The diameter of the peristome is a little
+larger than the length of the body. The ciliary disk is but little
+elevated. The cuticle is not striated and the body plasm is quite
+transparent. Length 52µ.
+
+
+[Illustration: Fig. 59.--_Vorticella patellina_.]
+
+
+Vorticella marina Greeff.  Fig. 60.
+
+The body is conical but variable, and may he short or elongate, so
+that relative length and breadth offer no chance of identification.
+In general the body is campanulate. The distinguishing feature is the
+transverse annulation of the bell.
+
+Small, but common, and grows in small social groups. Length 35µ.
+
+
+[Illustration: Fig. 60.--_Vorticella marina_.]
+
+
+Genus ZOOTHAMNIUM (Bory de St. Vincent 1824) Stein '38, '54.
+
+Colorless and highly contractile forms growing in small or large
+colonies. The form and structure of the individuals is not different
+from _Vorticella_. The colonies are usually richly branched upon
+the dichotomous plan and the entire colony is contractile. The main
+character is that with each division of the individual the stalk
+also divides, each daughter cell getting one-half of the parent stem.
+The stems therefore remain in communication, so that a simultaneous
+contraction results, and the colony as a whole is withdrawn. In some
+species so-called macrogonidia, or larger sexual individuals, are
+developed alongside the usual ones. Fresh and salt water.
+
+
+Zoothamnium elegans D'Udekem '64?  Fig. 61.
+
+The bodies are variable--peristomial border widely dilated, tapering
+and attenuate posteriorly. The pedicle is slender, smooth, and
+transparent, and branches sparsely at its distal extremity. There
+are but few zooids (3 to 4). The ciliary disk projects conspicuously
+beyond the peristomial border. The pharyngeal cleft is very distinct
+and extends beyond center of body. Length of body 80µ.
+
+
+[Illustration: Fig. 61.--_Zoothamnium elegans_.]
+
+
+Genus COTHURNIA (Ehr. '31) Clap. & Lach. '58.
+
+Colorless forms of medium size-in some cases they may be green
+by Zoochlorella. The general structure is similar to that of
+_Vorticella_, but the individuals are elongate and occupy houses. The
+macronucleus is invariably long and band-form. The distinguishing
+character is the colorless or brownish lorica of quite variable form
+but always attached. These houses may be finger-formed, with widened
+center, or widened mouth, or constricted mouth, and the like.
+Ring-formed swellings are frequently developed. Sometimes the mouth
+becomes twisted and the lorica is therefore bilateral. The houses
+are attached either directly to some foreign object or by means of
+a short stalk. The animals are similarly fastened to the lorica,
+sometimes directly, sometimes by means of a short stalk. When they
+contract they draw back to the bottom of the lorica; when expanded
+they usually stretch out of the mouth opening. In some forms there
+is an operculum, by means of which the opening of the shell can be
+closed when the animal is retracted. Fresh and salt water.
+
+The number of species of _Cothurnia_ has become so great that the
+difficulty in placing forms is almost sufficient to discourage the
+systematist; as Bütschli well remarks, the variations in the theca
+have been made the basis of new species so many times that the
+genus is almost as confused as _Difflugia_ among the rhizopods or
+_Campanularia_ among the hydroids. The length of cup, of stalk,
+the presence of annulations on stalk or cup, etc., have given rise
+to many specific names, the majority of which I believe can be
+discarded. According to such differentials the same branch of an alga
+holding a hundred specimens of _Cothurnia crystallina_ yield 10 or 12
+species, whereas they are merely growth stages of one and the same
+form.
+
+
+Cothurnia crystallina Ehr.  Fig. 62.
+
+Synonyms: _Vaginicolla crystallina_ Ehr., Perty, Eichwald; _V.
+grandis_ Perty; _V. pedunculata_ Eichwald; _Cothurnia crystallina_
+Claparède & Lachmann, D'Udek.; _C. gigantea_ D'Udek; _C. maritima_,
+_C. crystallina_ Cohn; _C. grandis_ Meresch.
+
+The form of the cup shows the greatest differences; sometimes it is
+cylindrical, sometimes elongate thimble-shape, sometimes pouch-shape,
+corrugated or smooth on the sides, and wavy or smooth on border.
+Frequently the basal part becomes stalk-like, but this is very short.
+When present, the stalk may or may not have a knob-like swelling. The
+animal within the cup may or may not be borne on a stalk, and this
+stalk may or may not be knobbed. The cups are colorless or brown. The
+animal is very contractile and may stretch half its length out of the
+cup or retract well into it. There is no operculum. The length of the
+cup varies from 70µ to 200µ (_C. gigantea_; _Vag. grandis_, etc.).
+From Entz.
+
+There is nothing to add to Entz's characterization of this species,
+which is found both in fresh and salt water. The variability of the
+cup and stalk is quite noticeable in the Woods Hole forms.
+
+
+[Illustration: Fig. 62.--_Cothurnia crystallina_.]
+
+
+Cothurnia imberbis Ehrenberg, var. curvula Entz.  Fig. 63.
+
+Synonyms: _C. imberbis_ Kent et al.; _C. curvula_ Entz; _C. socialis_
+Gruber?
+
+The lorica is swollen posteriorly, narrowest at the oral margin, bent
+on its axis and is supported on a short stalk. It is perfectly smooth
+and without annulations. The animal itself has no definite stalk.
+When fully expanded the animal emerges but slightly from the margin
+of the cup. Fresh and salt water. On red algæ. Dimensions of Woods
+Hole form: Cup 50 to 55µ long; greatest diameter 22µ; length of stalk
+4 to 5µ.
+
+
+[Illustration: Fig. 63.--_Cothurnia imberbis_.]
+
+
+Cothurnia nodosa Claparède & Lachmann.  Fig.64.
+
+   A. Smooth cup.--_Cothurnia maritima_ Ehr., Eichwald, Stein, Kent.
+
+   B. Cross-ringed cup.--_C. pupa_ Eichwald, Stein, Cohn; _C. nodosa_
+      Cl & L.; _V. crystallina_ Entz '78; _C. pontica_ Meresch.,
+      Kent; _C. cohnii_ and _pupa_ Kent; _C. longipes_ Kellicott '94.
+
+The cup is elongated, swollen centrally, tapering at oral end
+and conical at base or rounded. Oral opening either circular or
+elliptical. Cross rings may or may not be present, and the cup is
+either smooth or annulate. Length of cup 70µ to 80µ. The stalk which
+supports the cup is extremely variable in length. The animal is borne
+upon a stalk of variable length within the cup.
+
+Entz states that the many variations which this species exhibits run
+into each other so gradually that he does not believe it wise to
+separate them. The Woods Hole forms which I found on algæ of various
+kinds were nearly of a size, and did not vary much from the one
+figured. Kellicott '94 described a _Cothurnia_ from Woods Hole under
+the name of _C. longipes_, which I believe is only a long-stemmed
+variety of _C. nodosa_. My form has the following dimensions: Cup
+75µ; cup stalk 38µ; animal stalk 14µ.
+
+
+[Illustration: Fig. 64.--_Cothurnia nodosa_.]
+
+
+KEY TO FAMILIES OF SUCTORIA.
+
+a. Unattached forms; ventral cilia        _Hypocomidæ_
+   present; one suctorial tentacle
+
+b. Attached forms; thecate and            _Urnulidæ_
+   athecate tentacles simple,
+   one or two in number
+
+c. Thecate; posterior end of cup          _Metacinetidæ_
+   drawn out into stalk; walls
+   perforated for exit of tentacles
+
+d. Stalked or unstalked; globular;        _Podophryidæ_
+   tentacles of different kinds, some     (2 genera *_Ephelota_,
+   knobbed, others pointed                *_Podophrya_)
+
+e. Naked or thecate; stalked or not;      _Acinetidæ_
+   tentacles numerous, usually
+   knobbed and all alike
+
+f. Naked; athecate; tentacles             _Dendrosomidæ_
+   numerous, all alike, knobbed and
+   grouped in tufts. They may be
+   simple or branched.
+
+g. Sessile forms resting on basal         _Dendrocometidæ_
+   surface or on a portion raised
+   like a stalk; tentacles many;
+   short and knobbed; distributed
+   on apical surface or localized
+   on branched arms
+
+h. Stalked or sessile; tentacles          _Ophryodendridæ_
+   long, rarely knobbed, supported
+   on proboscis-like processes
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PODOPHRYA Ehr. '33.
+
+(Bütschli '88; Stein '59; Perty '52; Cienkowsky '55; Quenn. '69;
+Hertwig '77; Maupas '81.)
+
+The body is globular, with tentacles radiating in all directions. The
+tentacles may be very short or very long. The stalk also is either
+short or long, and some species form stalks but rarely (_P. libera_).
+The macronucleus is centrally placed and globular to ovoid in form.
+The contractile vacuole is usually single. Reproduction takes
+place by division; the distal half developing cilia and becoming a
+swarm-spore. Fresh and salt water.
+
+
+Podophrya gracilis, n. sp.  Fig. 65.
+
+Of all the _Podophrya_ that have been described not one approaches
+this minute form in the relative length of the stalk. The body is
+spherical and is covered with short capitate tentacles. The stalk is
+extremely slender, bent, and without obvious structure. There are
+one or two contractile vacuoles in the distal half of the body. The
+nucleus is small and is situated near the insertion-point of the
+stalk. Reproduction not observed. Diameter of body 8µ; length of
+stalk 40µ. Only one specimen seen.
+
+
+[Illustration: Fig. 65.--_Podophrya gracilis_.]
+
+
+Genus EPHELOTA Str. Wright '78.
+
+(Bütschli '88; Ishikawa '96; Sand '98.)
+
+Small to medium-sized and large forms; colorless to brown. The body
+is globular or oval or wedge-shape, sometimes quadrangular. The stalk
+is variable, sometimes 1 mm. in length. The diameter of the stalk
+increases from the point of attachment to the body of the animal;
+it is usually striated either longitudinally or transversely, or
+both. The tentacles are of two kinds and are usually confined to
+the anterior half of the body. Some are long and sharp-pointed
+and adapted for piercing; others are short, cylindrical, usually
+retracted and capitate, adapted for sucking. Contractile vacuoles
+vary from one to many. The macronucleus is nearly central in position
+and usually of horseshoe shape, but is frequently branched and
+irregular. Reproduction is accomplished by external multiple budding,
+usually from the anterior half of the body. Salt water.
+
+
+Ephelota coronata Str. Wright.  Fig. 66.
+
+Synonyms: _Hemiophrya gemmipara_ S. K.; _Podophrya gemmipara_
+Hertwig.
+
+The body is spheroidal, ovate, or pyriform, with numerous
+sharp-pointed tentacles and a few straight, uniform tentacles. The
+stalk is about three times the length of the body and tapers from its
+widest part at the insertion in the body to the narrowest part at the
+point of attachment. It may or may not be longitudinally striated.
+This is one of the commonest of the _Suctoria_ found at Woods Hole.
+It is usually present on Campanularian hydroids, but may be found on
+algæ and Bryozoa.
+
+Length of body 90µ to 200µ.
+
+
+[Illustration: Fig. 66.--_Ephelota coronata_.]
+
+
+Genus ACINETA Ehr. '33, Bütschli '88.
+
+(Stein '54, '59; Claparède & Lachman '58; Quennerstedt '67; Hertwig
+'76; Mereschowsky '79; Entz '84; Kent '81; Maupas '83; Gruber '84;
+Gourret & Roeser '86, and others.)
+
+Small to medium-sized forms. The distinguishing feature is that the
+stalk is swollen at the distal extremity to form a cup or basin in
+which the animal rests. The cup may be developed until the body is
+nearly inclosed. The macronucleus is spherical or band form. The
+contractile vacuole is usually single. Budding, so far as known, is
+endogenous. Fresh and salt water.
+
+
+Acineta divisa Fraipont '79.  Fig. 67.
+
+This extremely graceful form is common on Bryozoa at Woods Hole. The
+cup is shaped like a wine glass and is specifically characterized by
+a cup-formed membrane upon which the animal rests. The animal thus
+has the appearance of being suspended on the edge of the cup. The
+stalk is slender and about 4 times the length of the body. The
+tentacles are all capitate and distributed, and about 2-1/2 times the
+body length. They sway back and forth very slowly. The nucleus is
+spherical and central in position. The contractile vacuole lies near
+the periphery.
+
+Length of body 27µ; of stalk 100µ; of extended tentacle 65µ.
+
+
+[Illustration: Fig. 67.--_Acineta divisa_.]
+
+
+Acineta tuberosa Ehr.  Fig. 68.
+
+Large forms of _Suctoria_ with tentacles arranged in fascicles. The
+stalk is variable in length and the cup is frequently so delicate
+that it can barely be made out. A specific characteristic is the
+break in continuity of the cup at different points, and through these
+places the tentacles emerge in bundles. The tentacles are capitate
+and in the Woods Hole form, 15 in number in each of the two bundles.
+The endoplasm is granular and yellowish in color. The coloring matter
+is frequently arranged in patterns. The nucleus is spheroidal. The
+contractile vacuole is in the anterior third of the body about midway
+between the bundles of tentacles. Reproduction not observed.
+
+Length of body 330µ.
+
+
+[Illustration: Fig. 68.--_Acineta tuberosa_.]
+
+
+Genus TRICHOPHRYA Clap. & Lach. '58.
+
+(See Kent '81; Entz '84; Bütschli '88; Sand 1901.)
+
+Small forms to medium size; no cups or stalks. The body is spherical
+to elongate, usually, however, more or less irregularly lobed and
+changeable. The tentacles are in fascicles which are usually borne
+upon lobed or swollen places. The body is always more or less spread
+out. Contractile vacuoles variable. The macronucleus is spherical,
+elongate, band-formed or horseshoe-shaped. Reproduction takes place
+by endogenous budding, and the swarm spores are flat or lenticular
+with a distinct ciliary girdle. They are frequently parasitic. Fresh
+and salt water.
+
+
+Trichophrya salparum Entz '84.  Fig. 69.
+
+Bütschli '88; Schewiakoff '93; _Trichophrya ascidiarum_ Lachmann '59;
+René Sand 1901.
+
+The body is somewhat cup-form, with a large, flat base. The anterior
+border is rounded, each of the ends being somewhat truncate and
+carrying a bundle of tentacles all capitate and similar. These may be
+continued internally as far as the nucleus (Sand). The cytoplasm is
+uncolored, but may contain some brilliant granules. The nucleus is
+granular, and spherical, band or horseshoe formed.
+
+
+[Illustration: Fig. 69.--_Trichophrya salparum_.]
+
+
+This species was found by Dr. G. Hunter on the branchial bars of the
+Ascidian _Molgula manhattensis_, where great numbers of them are
+often parasitic.
+
+
+
+
+LIST OF REFERENCES.
+
+
+
+
+
+AUERBACH, L. '54. Ueber Encystierung von Oxytricha pellionella. Zeit.
+      wiss. Zool., V, 1854.
+
+---- '55. Ueber die Einzelligkeit der Amoeben. Zeit. wiss. Zool.,
+      VII, 1855.
+
+BALBIANI E. G. '61. Recherches sur les phénomènes sexuelles des
+      Infusoires. Jour. de la physiol:, IV, 1861.
+
+---- '85. Sur un Infusoire parasite du sang de l'Aselle aquatique.
+      Rec. zool. Suisse, II, 1885.
+
+BERGH, R. S. '79. _Tiarina fusus_ Cl. & Lach. Vid. Med. f. d. Nat.
+      Foren. Kjobenhavn.
+
+---- '82. Der Organismus der Cilioflagellaten.  Morph. Jahr., VII, p.
+      177.
+
+BRADY, H. B. '79. Report on the Foraminifera dredged by H. M. S.
+      _Challenger_ during the years 1873-1876. Challenger Reports,
+      Zoology, IX.
+
+BRANDT, K. '96. Die Tintinnodeen. Bibliot. Zoolog., XX, 1896.
+
+BÜTSCHLI, O. '76. Studien über die ersten Entwickelungsvorg. der
+      Eizelle, die Zelltheilung, und die Conjugation der Infusorien.
+      Abhand. der Senck. naturf. Ges. Freiburg, X, 1876.
+
+---- '83-'88. Die Protozoen. Bronn's Klassen u. Ord. des Tierreichs.
+
+CARPENTER, W. B. '56. Researches on the Foraminifera. Phil. Trans.
+      (2), p. 547.
+
+CARTER, H. J. '56. Notes on the fresh-water Infusoria of the island
+      of Bombay. Ann. Mag. Nat. Hist. (2), XVIII.
+
+---- '63. On the coloring matter of the Red Sea. Id. (3), XI.
+
+---- '63a. On _Amoeba princeps_ and its reproductive cells. Id. (3),
+      XII.
+
+---- '64. On fresh-water Rhizopods of England and India. Id. (3),
+      XIII, p. 13.
+
+---- '65. On the fresh- and salt-water Rhizopods of England and
+      India. Id. (3), XV, p. 277.
+
+CIENKOWSKY, L. '55. Bemerkungen über Stein's Acinetenlehre. Bull.
+      Phys. Math. Acad., St. Petersburg, XIII, p. 297 (also in Ann.
+      Mag. Nat. Hist. (3), XIII).
+
+---- '55. Ueber Cystenbildung bei Infusorien. Zeit. wiss. Zool., VI,
+      p. 301.
+
+---- '61. Beiträge zur Kenntniss der Monaden. Arch. f. mik. Anat., I,
+      1865, p. 203.
+
+CLAPARÈDE, E. '54. On _Actinophrys sol_. Ann. Mag. Nat. Hist. (2),
+      XV, 1854.
+
+---- '60. Recherches sur les annélides, etc., observés dans les
+      Hébrides. Mém. Soc. phys. d'hist. nat., Genève, XVI, 1860.
+
+---- '67. Miscellanées zoologiques. Ann. d. sc. nat. zool. (5), VIII,
+      1867.
+
+CLAPARÈDE ET LACHMANN '58-'60. Etudes sur les Infusoires et les
+      Rhizopodes. Mém. Inst. genèvoise, V, VI, VII.
+
+COHN, F. '54. Beiträge z. Entwicklungsges. der Infusorien. Zeit.
+      wiss. Zool. III, 1851; IV, 1853.
+
+---- '57. Ueber Fortpflanzung von _Nassula elegans_ Ehr. Zeit. wiss.
+      Zool., IX, 1857, p. 143.
+
+COSTE, M. '64. Développement des Infusoires ciliés dans une
+      macération de foin. Ann. d. ac. nat. zool.(5), II.
+
+DADAY, E. v. '86.  Ein kleiner Beitrag der Infusorien-Fauna des
+      Golfes v. Neapel. Mitt. Zool. St. Neap., VI, p. 481.
+
+---- '88. Monographie der Familie der Tintinnodeen. Mitt. Zool. St.
+      Neap., VIII, p. 473.
+
+DAVIS, J. '79. On a new species of Cothurnia. Jour. Roy. Mic. Soc.,
+      II, 1879.
+
+DUJARDIN, F. '35. Recherches sur les organismes inférieures. Ann. d.
+      sc. nat. zool. (2), IV, p. 343.
+
+---- '41. Histoire naturelle des Zoophytes infusoires. Paris, 1841.
+
+EHRENBERG, C. G. '31. Ueber die Entwickelung und Lebensdauer d.
+      Infusionsthiere. Abhand. d. Berlin Ak., 1831, p. 1.
+
+---- '38. Die Infusionsthierchen als vollkommne Organismen. Leipzig,
+      1838.
+
+ENGELMANN, Th. W. '78. Zur Physiologie der Contractilen Vacuolen der
+      Infusionsthiere.  Zool. Anz., I, p. 121.
+
+ENTZ, G. '84. Ueber Infusorien d. Golfes v. Neapel. Mitt. Zool. St.
+      Neap., V, p. 289.
+
+---- '85. Zur naheren Kenntniss der Tintinnodeen. Mitt. Zool. St.
+      Neap., VI, p. 185.
+
+FABRE-DOMERGUE, P. '85. Note sur les Infusoires ciliés de la baie de
+      Concarneau. Jour. d. l'anat. et de la phys., XXI, p. 554.
+
+---- '91. Matériaux pour servir a l'histoire des Infusoires ciliés.
+      Ann. d. mic., III, 1890-91, p. 49.
+
+FOL, H. '83. Further contribution to the knowledge of the
+      Tintinnodea. Ann. Mag. Nat. Hist. (5), XII, p.73.
+
+FRANCÉ, R. H. '97. Der organismus der Craspedomonaden. Budapest.
+
+FROMENTEL. E. DE. '74. Etudes sur les microzoaires, etc. Paris, 1874.
+
+GOURRET ET ROESER. '88. Contributions à l'étude des Protozoaires de
+      la Corse. Arch. d. biol., VIII  p. 139.
+
+GREEFF, R. '66. Ueber einige in der Erde lebende Amoeben und andere
+      Rhizopoden. Arch. f. mik. Anat., II, p. 299.
+
+---- '70. Untersuchungen ueber den Bau u. d. Naturgeschichte d.
+      Vorticellen. Arch. f. Naturges., XXXVI, XXXVII.
+
+---- '71. Ueber die Actinophryens oder Sonnenthierchen des
+      Süssenwassers als echte Radiolarien. Sitz. Ber. d. Niederrh.
+      Ges. i. Bonn, XXVIII, p. 4.
+
+---- '75. Ueber Radiolarien u. Radiolarienartige Rhizopoden des
+      Süssenwassers 2.  Arch. f. mik. Anat., XI.
+
+---- '88. Studien über Protozoen. Sitz. Ber. Ges. z. Bef. d. ges.
+      Nat., Marburg, 1888, p. 91.
+
+GRENACHER, H. '68.  Ueber _Actinophrys sol_ Ehr. Verh. phys.-med.
+      Ges. Freiburg (n. F.), I.
+
+GRUBER, A. '83. Beobachtungen an _Chilodon curvidentis_ n. sp.
+      Festschr. 56. Vers. Deutsch. Naturf. gewid. v. d. Naturf. Ges.
+      Freiburg, II, p. 1.
+
+---- '84. Die Protozoen des Hafens v. Genua. Nova Act. d. K.
+      Leop.-Car. Deutsch. Akad. d. Naturf., XLVI, p. 475.
+
+---- '87. Ueber der Bedeutung der Conjugation bei den Infusorien.
+      Ber. d. Naturf. Ges. Freiburg, II, p. 31.
+
+HÆCKEL, E. '73. Zur Morphologie der Infusorien.  Jena Zeit., VII, p.
+      516.
+
+HERTWIG, R. '76. Ueber _Podophrya gemmipara_, nebst Bemerkungen zum
+      Bau u. d. systemat. Stellung d. Acineten. Morph. Jahr., IV,
+      p. 20.
+
+HERTWIG U. LESSER. Ueber Rhizopoden u. denselben nahe stehende
+      Organismen. Arch. F. mik. Anat., X, Suppl., p. 35.
+
+HUXLEY, T. H. '57. On Dysteria, a new genus of Infusoria. Jour. Mic.
+      Sci., V, p. 78.
+
+ISHIKAWA, C. Ueber eine in Misaki vorkommende Art v. Ephelota, etc.
+      Journ. Coll. Sci. Imp. Univ. Tokyo, Japan, X, pt. 2.
+
+JAMES-CLARK, H. '66. On the Spongiæ ciliatæ as Infusoria flagellata,
+      etc. Mem. Bost. Soc. Nat. Hist. (3), I, p. 1.
+
+KENT, W. SAVILLE. '81. Manual of the Infusoria. London, 1881.
+
+KLEBS, G. '84. Ein kleiner Beitrag z. Kenntniss d. Peridineen. Bot.
+      Zeit., XLII, p. 721.
+
+---- '92. Flagellaten Studien 1. Zeit. wiss. Zool., LV.
+
+LABBÉ, A. '95. Sur les Protozoaires marins de Roscoff. Arch. d. zool.
+      expér. (3), N. et R., p. XIV.
+
+LAUTERBORN, R. '94. Beiträge z. Süsswasserfauna der Insel Helgoland.
+      Wiss. Meeresunt. Komm. wiss. Unt. d. Meere Kiel (2), I, p. 215.
+
+LEIDY, J. '77. Remarks upon Rhizopods and notice of a new form. Proc.
+      Ac. Sci. Phila., 1877, p. 293.
+
+---- '79. Fresh water Rhizopods of North America. Washington, 1879.
+
+LIEBERKÃœHN, N. '56. Ueber Protozoen.  Notes from a letter to C. Th.
+      v. Siebold. Zeit. wiss. Zool., VIII, p. 307.
+
+MAUPAS, E. '81. Contributions à l'étude des Acinétiens. Arch. d.
+      zool. expér. (1), IX, p. 299.
+
+---- '83. Contributions à l'étude morphologique et anatomique des
+      Infusoires ciliés. Id. (2), I.
+
+---- '83a. Les sucto-ciliés de M. Mereschowsky. Comp. Ren., XCV, p.
+      1381.
+
+---- '88. Recherches expérimentales sur la multiplication des
+      Infusoires ciliés. Arch. d. zool. exper. (2), VI, p. 165.
+
+MERESKOWSKY, C. '78. Studien über Protozoen des nordlichen Russland.
+      Arch. f. mik. Anat., XVI, p. 163.
+
+---- '81. On some new or little-known Infusoria. Ann. Mag. Nat. Hist.
+      (5), VII, 1881.
+
+MOEBIUS, K. '88. Bruchstücke einer Infusorienfauna der Kieler Bucht.
+      Arch. f. Naturg., 1888.
+
+PECK, J. I. '93. On the food of the menhaden. Bull. U. S. Fish Com.,
+      1893, p. 113.
+
+---- '95. The sources of marine food. Bull. U. S. Fish Com., 1895, p.
+      351.
+
+PERTY, M. '49. Mikrosk. Organ. der Alpen u. d. Italien. Schweiz.
+      Mitt. d. Naturf. Ges. in Bern, 164-165.
+
+---- '52. Zur Kenntniss kleinster Lebensformen, etc., Bern.
+
+POUCHET, G. '83; '85. Contributions à l'histoire des Péridiniens
+      marins. Jour. de l'anat. et de la phys., XIX, XXI.
+
+QUENNERSTEDT, A. '65; '67; '69. Bidrag till Sveriges Infusorie-fauna.
+      Lunds Univ. Ärsskrift, II, IV, VI.
+
+SAND, R. 1901. Etude monographique sur le groupe des Infusoires
+      tentaculifères. Ann. d. la Soc. belge de microscopie, XXIV,
+      XXV, XXVI.
+
+SCHAUDINN, F. '95. Die Heliozoen. Das Tierreich, 1895.
+
+SCHEWIAKOFF, W. '89. Beiträge z. Kenntniss der Holotrichen Ciliaten.
+      Bib. Zool., V, p. 1.
+
+---- '93. Ueber einige ecto- u. ento-parasitische Protozoen der
+      Cyclopiden. Bull. Soc. nat. Moscou, 1893. I.
+
+SCHUETT, F. '95. Die Peridineen d. Plankton-Expedition, 1. Kiel u.
+      Leipzig.
+
+SCHULTZE, F. E. '74; 75. Rhizopodenstudien. Arch. f. mik. Anat., X,
+      XI, XIII.
+
+SCHULTZE, M.  '62. Ueber d. Organismus d. Polythalamien. Leipzig,
+      1862.
+
+SHEVYAKOV ?. '96. Monograph on _Holotrichous ciliates_. (In Russian.)
+      Mem. of the St. Petersburg Acad., VII.
+
+STEIN, F. '59; '78; '83. Der Organismus der Infusionsthiere. I.
+      Infusoria, '59; II. Infusoria, '78; III. Flagellata, '83.
+
+---- '49. Untersuchung über die Entwicklungs d. Infusorien. Arch. f.
+      Natur., I, p. 92.
+
+---- '54. Die Infusionsthiere auf ihre Entwicklungsgeschichte
+      untersucht. Leipzig, 1854.
+
+---- '60. Ueber _Leucophrys patula_ u. über 2 neue
+      Infusoriengattungen Gyrocoris u. Lophomonas. Sitz. Ber. d.
+      K.-böhm. Ges. d. Wiss. d. Prag, 1860, p. 4.
+
+---- '64. Ueber die neue Gattung Epiclintes. Id., 1864, I.
+
+STERKI, V. '78. Beiträge z. Morphologie der Oxytrichinen.  Zeit.
+      wiss. Zool., XXXI, p. 29.
+
+---- '98. On the classification of ciliate Infusoria. Amer. Natur.,
+      XXXII, p. 425.
+
+STEVENS, N. M. 1901. Studies on ciliate Infusoria.  Proc. Calif.
+      Acad. Sciences, III, 1.
+
+STOKES, A. C. '84. Notices of some new parasitic Infusoria. Amer.
+      Nat., XVIII, p. 1081.
+
+---- '85. Some apparently undescribed Infusoria from fresh water.
+      Id., XIX, p. 18.
+
+---- '87. Some new hypotrichous Infusoria from American fresh waters.
+      Ann. Mag. Nat. Hist. (5), 20.
+
+TATEM, T. G. '67. New species of microscopic animals.  Q. J. M. S.
+      (n.s.), VII, p. 251.
+
+VEJDOWSKY, F. '79. Monographie der Enchytraeiden.  Prag, 1869.
+
+WALLENGREN, H. '94. Studier ofver ciliata Infusorier, 1. Slagtet
+      Lichnophora. Lund, 1894.
+
+WALLICH, G. C. '63. Observations on an undescribed indigenous Amoeba.
+      Ann. Mag. Nat. Hist. (3), XI, XII.
+
+WESTON, J. '56. On the _Actinophrys sol_. Q. J. M. S., IV, p. 116.
+
+WRZESNIOWSKI A. '61. Observations sur quelques Infusoires. Ann. d.
+      sc. nat. zool. (6), XVI.
+
+---- '69. Ein Beitrag zur Anatomie der Infusorien. Arch. f. mik.
+      Anat., V, p. 25.
+
+---- '70. Beobachtungen über Infusorien a. d. Umgebung v. Warschau.
+      Zeit. wiss. Zool., XX, p. 467.
+
+
+
+***END OF THE PROJECT GUTENBERG EBOOK MARINE PROTOZOA FROM WOODS HOLE***
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+<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
+<title>The Project Gutenberg eBook of Marine Protozoa from Woods Hole, by Gary N. Calkins</title>
+<style type="text/css">
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+<body>
+<h1>The Project Gutenberg eBook, Marine Protozoa from Woods Hole, by Gary N.
+Calkins</h1>
+<pre>
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at <a href = "http://www.gutenberg.org">www.gutenberg.org</a></pre>
+<p>Title: Marine Protozoa from Woods Hole</p>
+<p>       Bulletin of the United States Fish Commission 21:415-468, 1901</p>
+<p>Author: Gary N. Calkins</p>
+<p>Release Date: May 5, 2006  [eBook #18320]</p>
+<p>Language: English</p>
+<p>Character set encoding: UTF-8</p>
+<p>***START OF THE PROJECT GUTENBERG EBOOK MARINE PROTOZOA FROM WOODS HOLE***</p>
+<br><br><center>
+<h3>E-text prepared by Ronald Calvin Huber,<br>
+    while serving as Penobscot Bay Watch, Rockland, Maine,<br>
+    and Joseph E. Loewenstein, M.D.</h3>
+</center><br><br>
+<hr class="full" noshade>
+<br>
+<br>
+<br>
+<h3>From the <i>Bulletin of the United States Fish Commission</i> 21:415-468, 1901</h3>
+<br>
+<br>
+<hr class="narrow">
+<br>
+<br>
+
+<h3>Contributions from the Biological Laboratory of<br>
+the U. S. Fish Commission, Woods Hole, Massachusetts.</h3>
+<br>
+<br>
+<br>
+
+<h1>MARINE PROTOZOA<br>
+    FROM WOODS HOLE.</h1>
+<br>
+<br>
+
+<h4>by</h4>
+
+<h2>GARY N. CALKINS,</h2>
+<h3>Department of Zoology, Columbia University.</h3>
+<br>
+<br>
+<br>
+<br>
+
+<p>Comparatively little has been done in this country upon marine
+Protozoa. A few observations have been made by Kellicott, Stokes, and
+Peck, but these have not been at all complete. With the exception of
+Miss Stevens's excellent description of species of
+<a href="#Lichnophora1"><i>Lichnophora</i></a> I am
+aware of no single papers on individual forms. Peck ('93 and '95)
+clearly stated the economic position of marine Protozoa as sources of
+food, and I need not add to his arguments. It is of interest to know
+the actual species of various groups in any locality and to compare
+them with European forms. The present contribution is only the
+beginning of a series upon the marine Protozoa at Woods Hole, and the
+species here enumerated are those which were found with the algæ
+along the edge of the floating wharf in front of the Fish Commission
+building and within a space of about 20 feet. Many of them were
+observed in the water and algæ taken fresh from the sea; others were
+found only after the water had been allowed to stand for a few days
+in the laboratory. The tow-net was not used, the free surface
+Protozoa were not studied, nor was the dredge called into play. Both
+of these means of collecting promise excellent results, and at some
+future time I hope to take advantage of them.</p>
+
+<p>My observations cover a period of two months, from the 1st of July to
+the 1st of September. During that time I was able to study and
+describe 72 species representing 55 genera, all from the limited
+space mentioned above. In addition to these there are a few genera
+and species upon which I have insufficient notes, and these I shall
+reserve until opportunity comes to study them further.</p>
+
+<p>I take this opportunity to express my thanks to Dr. Hugh M. Smith for
+many favors shown me while at Woods Hole.</p>
+
+<p>In dealing with these marine forms from the systematic standpoint,
+two courses are open to the investigator. He may make numerous new
+species based upon minor differences in structure, or he may extend
+previous descriptions until they are elastic enough to cover the
+variations. The great majority of marine protozoa have been described
+from European waters, and the descriptions are usually not elastic
+enough to embrace the forms found at Woods Hole. I have chosen,
+however, to hold to the conservative plan of systematic work, and to
+make as few new species as possible, extending the older descriptions
+to include the new forms.</p>
+
+<p>The different classes of Protozoa, and orders within the classes, are
+distributed more or less in zones. Thus the Infusoria, including the
+Ciliata and the <a href="#Suctoria">Suctoria</a>, are
+usually littoral in their habitat,
+living upon the shore-dwelling, or attached, water plants and upon
+the animals frequenting them. It is to be expected, therefore, that
+in forms here considered there should be a preponderance of
+Infusoria. Flagellated forms are also found in similar localities,
+but on the Surface of the sea as well; hence the number described in
+these pages is probably only a small proportion of the total number
+of Mastigophora in this region. The Sarcodina, including the
+Foraminifera and the Radiolaria, are typically deep-sea forms and
+would not be represented by many types in the restricted locality
+examined at Woods Hole. Two species, <i>Gromia lagenoides</i> and
+<i>Truncatulina lobatula</i>, alone represent the great order of
+Foraminifera, while the still larger group of Radiolaria is not
+represented at all.</p>
+
+<p>The Protozoa described are distributed among the different orders as
+follows:*</p>
+
+<center>
+<table class="classtable" cellpadding=10><tr><td>
+Class SARCODINA.<br>
+<span class="ind2">Subclass <span class="smallcaps">Rhizopoda</span>.</span><br>
+<span class="ind4">Order <span class="smallcaps">Amœbida</span>.</span><br>
+<span class="ind10">1. <a href="#Amoeba_guttala"><i>Amœba guttula</i></a> Duj</span><br>
+<span class="ind10">2. <a href="#Amoeba_sp"><i>Amœba</i> sp.</a></span><br>
+<span class="ind10">3. <a href="#Trichosphaerium_sieboldi"><i>Trichosphærium sieboldi</i></a> Schn.</span><br>
+<span class="ind4">Order <span class="smallcaps">Reticulariida</span>.</span><br>
+<span class="ind6">Suborder <span class="smallcaps">Imperforina</span>.</span><br>
+<span class="ind10">4. <a href="#Gromia_lagenoides"><i>Gromia lagenoides</i></a> Gruber.</span><br>
+<span class="ind6">Suborder <span class="smallcaps">Perforina</span>.</span><br>
+<span class="ind10">5. <a href="#Truncatulina_lobatula"><i>Truncatulina lobatula</i></a> Walker &amp; Jacob.</span><br>
+<span class="ind2">Subclass <span class="smallcaps">Heliozoa</span>.</span><br>
+<span class="ind4">Order <span class="smallcaps">Aphrothoracida</span>.</span><br>
+<span class="ind10">6. <a href="#Actinophrys_sol"><i>Actinophrys sol</i></a> Ehr.</span><br>
+<span class="ind4">Order <span class="smallcaps">Chlamydophorida</span>.</span><br>
+<span class="ind10">7. <a href="#Heterophrys_myriapoda"><i>Heterophrys myriapoda</i></a> Archer.</span><br>
+Class <span class="smallcaps">Mastigophora</span>.<br>
+<span class="ind2">Subclass <a href="#Flagellidia"><span class="smallcaps">Flagellidia</span></a>.</span><br>
+<span class="ind4">Order <a href="#Monadida1"><span class="smallcaps">Monadida</span></a>.</span><br>
+<span class="ind10">8. <a href="#Mastigamoeba simplex"><i>Mastigamœba simplex</i></a>, n. sp.</span><br>
+<span class="ind10">9. <a href="#Codonoeca_gracilis"><i>Codonœca gracilis</i></a>, n. sp.</span><br>
+<span class="ind10">10. <a href="#Monas_sp"><i>Monas</i> sp.</a></span><br>
+<span class="ind4">Order <a href="#Choanoflagellida"><span class="smallcaps">Choanoflagellida</span></a>.</span><br>
+<span class="ind10">11. <a href="#Monosiga_ovata"><i>Monosiga ovata</i></a> S. Kent.</span><br>
+<span class="ind10">12. <a href="#Monosiga_fusiformis"><i>Monosiga fusiformis</i></a> S. Kent.</span><br>
+<span class="ind10">13. <a href="#Codonosiga_botrytis"><i>Codonosiga botrytis</i></a> (Ehr.) J. Cl.</span><br>
+<span class="ind4">Order <a href="#Heteromastigida"><span class="smallcaps">Heteromastigida</span></a>.</span><br>
+<span class="ind10">14. <a href="#Bodo_globosus"><i>Bodo globosus</i></a> Stein.</span><br>
+<span class="ind10">15. <a href="#Bodo_caudatus"><i>Bodo caudatus</i></a> (Duj.) Stein.</span><br>
+<span class="ind10">16. <a href="#Oxyrrhis_marina"><i>Oxyrrhis marina</i></a> Duj.</span><br>
+<span class="ind4">Order <a href="#Euglenida"><span class="smallcaps">Euglenida</span></a>.</span><br>
+<span class="ind10">17. <a href="#Astasia_contorta"><i>Astasia contorta</i></a> Duj.</span><br>
+<span class="ind10">18. <a href="#Anisonema_vitrea"><i>Anisonema vitrea</i></a> Duj.</span><br>
+<span class="ind4">Order <span class="smallcaps">Silicoflagellida</span>.</span><br>
+<span class="ind10">19. <a href="#Distephanus_speculum"><i>Distephanus speculum</i></a> Stöhr.</span><br>
+<span class="ind2">Subclass <a href="#Dinoflagellidia"><span class="smallcaps">Dinoflagellidia</span></a>.</span><br>
+<span class="ind4">Order <span class="smallcaps">Adinida</span>.</span><br>
+<span class="ind10">20. <a href="#Exuviaella_lima"><i>Exuviælla lima</i></a> Clenk.</span><br>
+<span class="ind10">21. <a href="#Exuviaella_marina"><i>Exuviælla marina</i></a> Clenk.</span><br>
+<span class="ind4">Order <span class="smallcaps">Diniferida</span>.</span><br>
+<span class="ind10">22. <a href="#Gymnodinium_gracile"><i>Gymnodinium gracile</i></a> Bergh.</span><br>
+<span class="ind10">23. <a href="#Glenodinium_cinctum"><i>Glenodinium cinctum</i></a> Ehr.</span><br>
+<span class="ind10">24. <a href="#Glenodinium_compressa"><i>Glenodinium compressa</i></a>, n. sp.</span><br>
+<span class="ind10">25. <a href="#Peridinium_digitale"><i>Peridinium digitale</i></a> Pouchet.</span><br>
+<span class="ind10">26. <a href="#Peridinium_divergens"><i>Peridinium divergens</i></a> Ehr.</span><br>
+<span class="ind10">27. <a href="#Ceratium_tripos"><i>Ceratium tripos</i></a> Nitsch.</span><br>
+<span class="ind10">28. <a href="#Ceratium_fusus"><i>Ceratium fusus</i></a> Ehr.</span><br>
+<span class="ind10">29. <a href="#Amphidinium_operculatum"><i>Amphidinium operculatum</i></a> Clap. &amp; Lach.</span><br>
+Class <span class="smallcaps">Infusoria</span>.<br>
+<span class="ind2">Subclass <span class="smallcaps">Ciliata</span>.</span><br>
+<span class="ind4">Order <a href="#Holotrichida"><span class="smallcaps">Holotrichida</span></a>.</span><br>
+<span class="ind8">Family <a href="#Enchelinidae"><span class="smallcaps">Enchelinidæ</span></a>.</span><br>
+<span class="ind10">30. <a href="#Lacrymaria_lagenula"><i>Lacrymaria lagenula</i></a> Cl. &amp; Lach.</span><br>
+<span class="ind10">31. <a href="#Lacrymaria_coronata"><i>Lacrymaria coronata</i></a> Cl. &amp; Lach.</span><br>
+<span class="ind10">32. <a href="#Trachelocerca_phoenicopterus"><i>Trachelocerca phœnicopterus</i></a> Cohn.</span><br>
+<span class="ind10">33. <a href="#Tiarina_fusus"><i>Tiarina fusus</i></a> Cl. &amp; Lach.</span><br>
+<span class="ind10">34. <a href="#Mesodinium_cinctum"><i>Mesodinium cinctum</i></a>, n. sp.</span><br>
+<span class="ind8">Family <a href="#Trachylinidae"><span class="smallcaps">Trachylinidæ</span></a>.</span><br>
+<span class="ind10">35. <a href="#Lionotus_fasciola"><i>Lionotus fasciola</i></a> Ehr.</span><br>
+<span class="ind10">36. <a href="#Loxophyllum_setigerum"><i>Loxophyllum setigerum</i></a> Quenn.</span><br>
+<span class="ind8">Family <a href="#Chlamydodontidae"><span class="smallcaps">Chlamydodontidæ</span></a>.</span><br>
+<span class="ind10">37. <a href="#Nassula_microstoma"><i>Nassula microstoma</i></a> Cohn.</span><br>
+<span class="ind10">38. <a href="#Chilodon_cucullulus"><i>Chilodon cucullulus</i></a> M&uuml;ll.</span><br>
+<span class="ind10">39. <a href="#Dysteria_lanceolata"><i>Dysteria lanceolata</i></a> Cl. &amp; Lach.</span><br>
+<span class="ind8">Family <a href="#Chiliferidae"><span class="smallcaps">Chiliferidæ</span></a>.</span><br>
+<span class="ind10">40. <a href="#Frontonia_leucas"><i>Frontonia leucas</i></a> Ehr.</span><br>
+<span class="ind10">41. <a href="#Colpidium_colpoda"><i>Colpidium colpoda</i></a> Ehr.</span><br>
+<span class="ind10">42. <a href="#Uronema_marina"><i>Uronema marina</i></a> Duj.</span><br>
+<span class="ind8">Family <a href="#Pleuronemidae"><span class="smallcaps">Pleuronemidæ</span></a>.</span><br>
+<span class="ind10">43. <a href="#Pleuronema_chrysalis"><i>Pleuronema chrysalis</i></a> Ehr.</span><br>
+<span class="ind10">44. <a href="#Pleuronema_setigera"><i>Pleuronema setigera</i></a>, n. sp.</span><br>
+<span class="ind10">45. <a href="#Lembus_infusionum"><i>Lembus infusionum</i></a>, n. sp.</span><br>
+<span class="ind10">46. <a href="#Lembus_pusillus"><i>Lembus pusillus</i></a> Quenn.</span><br>
+<span class="ind8">Family <a href="#Opalinidae"><span class="smallcaps">Opalinidæ</span></a>.</span><br>
+<span class="ind10">47. <a href="#Anoplophrya_branchiarum"><i>Anoplophrya branchiarum</i></a> Stein.</span><br>
+<span class="ind4">Order <a href="#Heterotrichida"><span class="smallcaps">Heterotrichida</span></a>.</span><br>
+<span class="ind8">Family <a href="#Bursaridae1"><span class="smallcaps">Bursaridæ</span></a>.</span><br>
+<span class="ind10">48. <a href="#Condylostoma_patens"><i>Condylostoma patens</i></a> M&uuml;ll.</span><br>
+<span class="ind8">Family <span class="smallcaps">Halteridæ</span>.</span><br>
+<span class="ind10">49. <a href="#Strombidium_caudatum"><i>Strombidium caudatum</i></a> From.</span><br>
+<span class="ind8">Family <a href="#Tintinnidae1"><span class="smallcaps">Tintinnidæ</span></a>.</span><br>
+<span class="ind10">50. <a href="#Tintinnopsis_beroidea"><i>Tintinnopsis beroidea</i></a> Stein.</span><br>
+<span class="ind10">51. <a href="#Tintinnopsis_davidoffi"><i>Tintinnopsis davidoffi</i></a> Daday.</span><br>
+<span class="ind4">Order <a href="#Hypotrichida"><span class="smallcaps">Hypotrichida</span></a>.</span><br>
+<span class="ind8">Family <a href="#Peritromidae"><span class="smallcaps">Peritromidæ</span></a>.</span><br>
+<span class="ind10">52. <a href="#Peritromus emmae"><i>Peritromus emmæ</i></a> Stein.</span><br>
+<span class="ind8">Family <a href="#Oxytrichidae"><span class="smallcaps">Oxytrichidæ</span></a>.</span><br>
+<span class="ind10">53. <a href="#Epiclintes_radiosa"><i>Epiclintes radiosa</i></a> Quenn.</span><br>
+<span class="ind10">54. <a href="#Amphisia_kessleri"><i>Amphisia kessleri</i></a> Wrzes.</span><br>
+<span class="ind8">Family <a href="#Euplotidae"><span class="smallcaps">Euplotidæ</span></a>.</span><br>
+<span class="ind10">55. <a href="#Euplotes_charon"><i>Euplotes charon</i></a> Ehr.</span><br>
+<span class="ind10">56. <a href="#Euplotes_harpa"><i>Euplotes harpa</i></a> Stein.</span><br>
+<span class="ind10">57. <a href="#Diophrys_appendiculatus"><i>Diophrys appendiculatus</i></a> Stein.</span><br>
+<span class="ind10">58. <a href="#Uronychia_setigera"><i>Uronychia setigera</i></a>, n. sp.</span><br>
+<span class="ind10">59. <a href="#Aspidisca_hexeris"><i>Aspidisca hexeris</i></a> Quenn.</span><br>
+<span class="ind10">60. <a href="#Aspidisca_polystyla"><i>Aspidisca polystyla</i></a> Stein.</span><br>
+<span class="ind4">Order <a href="#Peritrichida"><span class="smallcaps">Peritrichida</span></a>.</span><br>
+<span class="ind8">Family <a href="#Lichnophoridae1"><span class="smallcaps">Lichnophoridæ</span></a>.</span><br>
+<span class="ind10">61. <a href="#Lichnophora_macfarlandi"><i>Lichnophora macfarlandi</i></a> Stevens.</span><br>
+<span class="ind8">Family <a href="#Vorticellidae"><span class="smallcaps">Vorticellidæ</span></a>.</span><br>
+<span class="ind10">62. <a href="#Vorticella_marina"><i>Vorticella marina</i></a> Greeff.</span><br>
+<span class="ind10">63. <a href="#Vorticella_patellina"><i>Vorticella patellina</i></a> M&uuml;ller.</span><br>
+<span class="ind10">64. <a href="#Zoothamnium_elegans"><i>Zoothamnium elegans</i></a> D'Udek.</span><br>
+<span class="ind10">65. <a href="#Cothurnia_crystallina"><i>Cothurnia crystallina</i></a> Ehr.</span><br>
+<span class="ind10">66. <a href="#Cothurnia_nodosa"><i>Cothurnia nodosa</i></a> Cl. &amp; Lach.</span><br>
+<span class="ind10">67. <a href="#Cothurnia_imberbis"><i>Cothurnia imberbis</i></a> Ehr.</span><br>
+<span class="ind2">Subclass <a href="#Suctoria1"><span class="smallcaps">Suctoria</span></a>.</span><br>
+<span class="ind8">Family <a href="#Podophryidae"><span class="smallcaps">Podophryidæ</span></a>.</span><br>
+<span class="ind10">68. <a href="#Podophrya_gracilis"><i>Podophrya gracilis</i></a>, n. sp.</span><br>
+<span class="ind10">69. <a href="#Ephelota_coronata"><i>Ephelota coronata</i></a> Wright.</span><br>
+<span class="ind8">Family <a href="#Acinetidae"><span class="smallcaps">Acinetidæ</span></a>.</span><br>
+<span class="ind10">70. <a href="#Acineta_divisa"><i>Acineta divisa</i></a> Fraip.</span><br>
+<span class="ind10">71. <a href="#Acineta_tuberosa"><i>Acineta tuberosa</i></a> Ehr.</span><br>
+<span class="ind8">Family <a href="#Dendrosomidae"><span class="smallcaps">Dendrosomidæ</span></a>.</span><br>
+<span class="ind10">72. <a href="#Trichophrya_salparum"><i>Trichophrya salparum</i></a> Entz.</span><br>
+<br>* This classification includes only the orders and families
+represented at Woods Hole
+</td></tr></table>
+</center>
+
+<br>
+<br>
+<br>
+<h3>Genus AM&OElig;BA Auct.</h3>
+
+<p>The pseudopodia are lobose, sometimes absent, the body then
+progressing by a flowing movement; the body consists of ectoplasm and
+endoplasm, the latter being granular and internal, the former hyaline
+and external. There is always one nucleus and one vacuole, but both
+may be more numerous. Reproduction takes place by division or by
+spore-formation. Fresh-water and marine.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_01.jpg">
+<img src="images/fig_01t.jpg" width="55" border=0
+alt="Amoeba guttala"></a>
+<br>
+<b>Fig. 1.&mdash;<br>
+<i>Amœba guttala</i>.</b><br>
+<a href="images/fig_01.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+<a name="Amoeba_guttala"></a>
+<br>
+<p class="noindent"><b>Amœba guttala</b> Duj.  Fig. 1.</p>
+
+<p>A minute form without pseudopodial processes, extremely hyaline in
+appearance, and characterized by rapid flowing in one direction. The
+body is club-shape and moves with the swollen end in advance. A
+comparatively small number of large granules are found in the swollen
+portion, while the smaller posterior end is quite hyaline.
+Contractile vacuole absent, and a nucleus was not seen.  Frequent in
+decomposing vegetable matter. Length 37&micro;. Traverses a distance of
+160&micro; in one minute.</p>
+
+<p>The fresh-water form of <i>A. guttula</i> has a vacuole, otherwise
+Dujardin's description agrees perfectly with the Woods Hole forms.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_02.jpg">
+<img src="images/fig_02t.jpg" width="200" border=0
+alt="Amoeba sp."></a>
+<br>
+<b>Fig. 2.&mdash;<i>Amœba</i> sp.</b>
+<br>
+<a href="images/fig_02.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<a name="Amoeba_sp"></a>
+<br >
+<p class="noindent"><b>Amœba ?</b>  Fig. 2.</p>
+
+<p>A more sluggish form than the preceding, distinguished by its larger
+size, its dense granulation, and by short, rounded pseudopodia,
+which, as in <i>Amœba proteus</i>, may come from any part of the body. A
+delicate layer of ectoplasm surrounds the granular endoplasm, and
+pseudopodia formation is eruptive, beginning with the accumulation of
+ectoplasm. Movement rapid, usually in one direction, but may be
+backwards or sideways, etc. Contractile vacuole absent; the nucleus
+is spherical and contains many large chromatin granules. Length 80&micro;;
+diameter 56&micro;.</p>
+
+
+<br>
+<br>
+<br>
+<h3>Genus TRICHOSPH&AElig;RIUM Schneider '78</h3>
+
+<p class="syn">Synonym: <i>Pachymyxa hystrix</i> Gruber.</p>
+
+<p>Marine rhizopods, globular or irregular in form, and slow to change
+shape. Dimorphic. Both forms multinucleate during vegetative life.
+Pseudopodia are long, thin, and thread-form, with rounded ends. Their
+function is neither food-getting nor locomotion, but probably
+tasting. The plasm of both forms is inclosed in a soft gelatinous
+membrane. In one form the jelly is impregnated with needles of
+magnesium carbonate (Schaudinn), but these are absent in the other
+form. The membrane is perforated by clearly defined and permanent
+holes for the exit of the pseudopodia. Reproduction occurs by
+division, by budding or by fragmentation, but the parts are
+invariably multinucleate. At the end of vegetative life the
+needle-bearing form fragments into numerous mononucleate parts; these
+develop into adults similar to the parent, but without the spines. At
+the end of its vegetative life this new individual fragments into
+biflagellated swarm-spores which may conjugate, reproducing the form
+with needles. Size up to 2 mm.</p>
+
+
+<a name="Trichosphaerium_sieboldi"></a>
+<br >
+<p class="noindent"><b>Trichosphærium sieboldi</b> Schneider.  Fig. 3.</p>
+
+<p>With the characters of the genus. A form which I have taken to be a
+young stage of this interesting rhizopod is described as follows:</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_03.jpg">
+<img src="images/fig_03t.jpg" width="190" border=0
+alt="Trichosphaerium sieboldi"></a>
+<br>
+<b>Fig. 3.&mdash;<br>
+<i>Trichosphærium sieboldi</i>.</b>
+<br>
+<br>
+<a href="images/fig_03.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+<p>A minute, almost quiescent, form which changes its contour very
+slowly. The membrane is cap-like and extends over the dome-shaped
+body, fitting the latter closely. The  endoplasm is granular and
+contains foreign food-bodies. Nucleus single, spherical, and
+centrally located. Pseudopodia short and finger-form, emerging from
+the edge of the mantle-opening and swaying slowly from side to side
+or quiescent. The most characteristic feature is the presence of a
+broad, creeping sole, membranous in nature and hyaline in appearance.
+This membrane is the only evidence of ectoplasm, and it frequently
+shows folds and wrinkles, while its contour slowly changes with
+movements of body. The pseudopodia emerge from the body between this
+membrane and the shell margin. Contractile vacuole absent. Length
+42&micro;, width 35&micro;. In decomposing seaweeds, etc.</p>
+
+<p>Only one specimen of this interesting form was seen, and I hesitate
+somewhat in placing it on such a meager basis. It is so peculiar,
+however, that attention should be called to it in the hope of getting
+further light upon its structure and mode of life. Its membranous
+disk recalls the genus <i>Plakopus</i>; its mononucleate condition, its
+membranous disk, and the short, sometimes branched, pseudopodia make
+it difficult to identify with any phase in the life-history of
+<i>Trichosphærium</i>. I shall leave it here provisionally, with the hope
+that it may be found more abundantly another time.</p>
+
+<br>
+<br>
+<br>
+<h3>Genus GROMIA Dujardin '35.</h3>
+
+<div class="center"><span class="syn">(Dujardin 1835; M. Schultze '62;
+F. E. Schultze '74;<br>
+Leidy '77; B&uuml;tschli '83; Gruber '84.)</span></div>
+
+<p>The form is ovoid or globular, and the body is covered by a tightly
+fitting, plastic, chitin shell, which, in turn, is covered by a fine
+layer of protoplasm. The flexibility of the shell makes the form
+variable as in the amœboid types. The thickness of the shell is
+quite variable. The pseudopodial opening is single and terminal. The
+pseudopodia are very fine, reticulate, granular, and sharply pointed,
+and form a loose network outside of the shell opening. Nucleus single
+or multiple. Contractile vacuole is usually absent. Fresh and salt
+water.</p>
+
+
+<a name="Gromia_lagenoides"></a>
+<br >
+<p class="noindent"><b>Gromia lagenoides</b> Gruber '84.  Fig. 4.</p>
+
+
+<p>This species is not uncommon about Woods Hole, where it is found upon
+the branches of various types of algæ. The body is pyriform, with the
+shell opening at the larger end. The chitinous shell is hyaline and
+plastic to a slight extent, so that the body is capable of some
+change in shape. The shell is thin and turned inwards at the
+mouth-opening, forming a tube (seen in optical section in fig. 4)
+through which the protoplasm passes to the outside. The walls of this
+tube are thicker than the rest of the shell, and in optical section
+the effect is that of two hyaline bars extending into the body
+protoplasm. A thin layer of protoplasm surrounds the shell and fine,
+branching, pseudopodia are given off in every direction. The
+protoplasm becomes massed outside of the mouth-opening and from here
+a dense network of pseudopodia forms a trap for diatoms and smaller
+Protozoa. The nucleus is spherical and contains one or two large
+karyosomes. The protoplasm is densely and evenly granular, without
+regional differentiation. I have never observed an external layer of
+foreign particles, such as Gruber described in the original species.</p>
+
+<p>Length of shell 245&micro;; largest diameter 125&micro;.</p>
+
+<table class="imagetable" align="center"><tr><td>
+<center>
+<a href="images/fig_04.jpg">
+<img src="images/fig_04t.jpg" width="450" border=0
+alt="Gromia lagenoides"></a>
+<br>
+<b>Fig. 4.&mdash;<i>Gromia lagenoides</i>.</b>&nbsp;&nbsp;
+<a href="images/fig_04.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+<br>
+<br>
+<br>
+<h3>Genus TRUNCATULINA D'Orbigny.</h3>
+
+<p>A group of extremely variable foraminifera in which the shell is
+rotaline; i. e., involute on the lower side and revolute on the upper
+(Brady). The shell is calcareous and coarsely porous in older forms.
+The characters are very inconstant, and Brady gives up the attempt to
+distinguish the group by precise and constant characters.</p>
+
+
+<a name="Truncatulina_lobatula"></a>
+<br >
+<p class="noindent"><b>Truncatulina lobatula</b> Walker &amp; Jacob.</p>
+
+<p class="syn">Synonyms: See Brady '84 for a long list.</p>
+
+<p>"It is impossible to define by any precise characters the
+morphological range of the present species. Its variations are
+infinite." (Brady, p. 660.)</p>
+
+<p>This very common form, which occurs in all latitudes, was found
+frequently among the algæ at Woods Hole. Its characters are so
+difficult to define that for the present I shall limit my record to
+this brief notice. Size of shell 230&micro; by 270&micro;.</p>
+
+
+<br>
+<br>
+<br>
+<h3>Genus ACTINOPHRYS Ehr.</h3>
+
+
+<p>The body is spherical and differentiated into granular endoplasm and
+vacuolated ectoplasm, but the zones are not definitely separated.
+There is one central nucleus and usually one contractile vacuole. The
+pseudopodia have axial filaments that can be traced to the periphery
+of the nucleus.  Fresh and salt water.</p>
+
+
+<a name="Actinophrys_sol"></a>
+<br >
+<p class="noindent"><b>Actinophrys sol</b> Ehr., variety.  Fig. 5.</p>
+
+<p class="syn">Synonyms: See Schaudinn '95.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_05.jpg">
+<img src="images/fig_05t.jpg" width="270" border=0
+alt="Actinophrys sol"></a>
+<br>
+<b>Fig. 5.&mdash;<i>Actinophrys sol</i>.</b>
+<br>
+<br>
+<a href="images/fig_05.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The diameter is about 50&micro;; the vacuolated ectoplasm passes gradually
+into the granular endoplasm. This is the characterization given <i>A.
+sol</i> by Schaudinn, and it applies perfectly to the freshwater forms.
+If I am correct, however, in placing an <i>Actinophrys</i>-like form found
+at Woods Hole in this species, the description will have to be
+somewhat modified. In this form (fig. 5) there is no distinction
+between ectoplasm and endoplasm, and there is an entire absence of
+vacuoles. The nucleus is central, and axial filaments were not seen.
+The single specimen that I found looked much like a Suctorian of the
+genus <i>Sphærophrya</i>, but the absence of a firm cuticle and the
+presence of food-taking pseudopodia with granule-streaming makes it a
+very questionable Suctorian, and 1 place it here until further study
+throws more light upon it.</p>
+
+<p>Diameter of body 40&micro;; length of pseudopodia 120 to 140&micro;.</p>
+
+
+<br>
+<br>
+<br>
+<h3>Genus HETEROPHRYS Archer.</h3>
+
+<p>The body is globular with but slight differentiation into ectoplasm
+and endoplasm; one nucleus in the latter; contractile vacuoles one or
+many; pseudopodia on all sides, thin, and with peripheral
+granule-streaming; surrounded by a globular, rather thick coat of
+jelly, which is hyaline inside and granular on the periphery. Fresh
+and salt water.</p>
+
+
+<a name="Heterophrys_myriapoda"></a>
+<br >
+<p class="noindent"><b>Heterophrys myriapoda</b> Archer.  Fig. 6.</p>
+
+<p class="syn">Synonym: <i>H. marina</i> Hert. &amp; Less. '74.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_06.jpg">
+<img src="images/fig_06t.jpg" width="300" border=0
+alt="Heterophrys myriapoda"></a>
+<br>
+<b>Fig. 6.&mdash;<i>Heterophrys myriapoda</i>.</b>
+<br>
+<a href="images/fig_06.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>Diameter 25 to 80&micro;; pseudopodia twice as long as the body diameter;
+the plasm often contains chlorophyll bodies (Zoochlorella). The
+granular part of the gelatinous layer is thick (up to 10&micro;). The
+spine-like processes are very thin and short. (Schaudinn '95.) The
+marine form found at Woods Hole probably belongs to this species, as
+described by Schaudinn. The short pseudopodia which give to the
+periphery a fringed appearance are quite regularly placed in
+connection with the pseudopodia. The latter are not so long as twice
+the body diameter, the longest being not more than equal to the
+diameter of the sphere. The body inside of the gelatinous covering is
+thickly coated with bright yellow cells similar to those on
+Radiolaria. The animal moves slowly along with a rolling motion
+similar to that described by P&egrave;nard '90, in the case of
+<i>Acanthocystis</i>. Diameter of entire globe 35&micro;; of the body without
+the jelly 18&micro;. The extremely fine granular pseudopodia are 8 to 35&micro;
+long. Common among algæ.</p>
+
+<p>This form was probably meant by Peck '95, when be figured "a
+heliozoön."</p>
+
+
+<br><a name="Flagellidia"></a><a name="Monadida1"></a>
+<br>
+<center>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="2" align="center">
+      <b><i>Key to orders of Flagellidia</i>.</b>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Small, body usually amœboid; 1 or more flagella; no mouth
+    </td>
+    <td valign="top">
+      Order <a href="#Monadida2"><span class="smallcaps">Monadida</span></a>.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Small; plasmic collar around the flagellum
+    </td>
+    <td valign="top">
+      Order <a href="#Choanoflagellida"><span class="smallcaps">Choanoflagellida</span></a>.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      With 2 or more flagella; one trails behind
+    </td>
+    <td valign="top">
+      Order <a href="#Heteromastigida"><span class="smallcaps">Heteromastigida</span></a>.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      With 3 or more flagella, none of which trails
+    </td>
+    <td valign="top">
+      Order <a href="#Polymastigida"><span class="smallcaps">Polymastigida</span></a>.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Large; firm body wall; 1 or 2 flagella; mouth or pharynx, or both
+    </td>
+    <td valign="top">
+      Order <a href="#Euglenida"><span class="smallcaps">Euglenida</span></a>.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Medium size; with chlorophyll, no mouth, usually colonial
+    </td>
+    <td valign="top">
+      Order <span class="smallcaps">Phytoflagellida</span>.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Small; silicious skeleton; parasitic on Radiolaria or free
+    </td>
+    <td valign="top">
+      Order <span class="smallcaps">Silicoflagellida</span>.<br>
+      (One genus,<br>
+      <a href="#Distephanus"><i>Distephanus</i></a> Stöhr)
+    </td>
+  </tr>
+</table>
+<br>
+<a name="Monadida2"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="2" align="center">
+      <b><i>Key to the families of Monadida.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      No mouth; 1 or 2 flagella: amœboid with lobose or ray-like pseudopodia
+    </td>
+    <td valign="top">
+      Family <a href="#Rhizomastigidae"><i>Rhizomastigidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Mouth at base of single flagellum; plastic; no pseudopodia
+    </td>
+    <td valign="top">
+      Family <i>Cercomonadidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      One flagellum; inclosed in gelatinous or membranous cups
+    </td>
+    <td valign="top">
+      Family <a href="#Codonoecidae"><i>Codonœcidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      One flagellum; tentacle like process at base of flagellum; inclosed in cup
+    </td>
+    <td valign="top">
+      Family <i>Bikœcidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      One main flagellum and 1 or 2 accessory flagella
+    </td>
+    <td valign="top">
+      Family <i>Heteromonadidæ</i>
+    </td>
+  </tr>
+</table>
+<br>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to marine genera of Monadida</i>.</b>*
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" valign="top">
+      <a name="Rhizomastigidae"></a>Family <i>Rhizomastigidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Flagellum repeatedly thrown off and reassumed
+    </td>
+    <td valign="top">
+      Genus *<a href="#Mastigamoeba"><i>Mastigamœba</i></a> in part
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      Flagellum never thrown off
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="55%" valign="top">
+      a. Pseudopodia lobose
+    </td>
+    <td valign="top">
+      Genus <a href="#Mastigamoeba"><i>Mastigamœba</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      b. Pseudopodia ray-like
+    </td>
+    <td valign="top">
+      Genus <i>Mastigophrys</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" valign="top">
+      <a name="Codonoecidae"></a>Family <i>Codonœcidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Goblet-shaped cups adherent by stalk
+    </td>
+    <td valign="top">
+      Genus *<a href="#Codonoeca"><i>Codonœca</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" valign="top">
+      Family <i>Heteromonadidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      The long flagellum vibratory
+    </td>
+    <td valign="top">
+      Genus *<a href="#Monas"><i>Monas</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      The long flagellum rigid; shorter one vibrates
+    </td>
+    <td valign="top">
+      Genus <i>Sterromonas</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+<br><a name="Choanoflagellida"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="6" align="center">
+      <b><i>Key to marine genera of Choanoflagellida</i>.</b>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      1.
+    </td>
+    <td valign="top" colspan="4">
+      Without gelatinous or membranous test
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      2.
+    </td>
+    <td valign="top" colspan="4">
+      With gelatinous or membranous test
+    </td>
+    <td valign="top">
+      4
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      3.
+    </td>
+    <td valign="top">
+      a.
+    </td>
+    <td colspan="3">
+      Attached forms:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td valign="top" width="3%">
+      &nbsp;
+    </td>
+    <td width="5%" align="right">
+      &nbsp;
+    <td width="5%" valign="top">
+      1.
+    </td>
+    <td width="40%">
+      Without a stalk, or with a very short one
+    </td>
+    <td valign="top">
+      Genus *<a href="#Monosiga"><i>Monosiga</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      &nbsp;
+    </td>
+    <td valign="top" width="3%">
+      &nbsp;
+    </td>
+    <td width="3%" align="right">
+      &nbsp;
+    <td valign="top">
+      2.
+    </td>
+    <td width="41%">
+      With a long, simple stalk
+    </td>
+    <td valign="top">
+      Genus *<a href="#Codonosiga"><i>Codonosiga</i></a>
+    </td>
+  <tr>
+    <td valign="top" align="right">
+      &nbsp;
+    </td>
+    <td valign="top" width="3%">
+      &nbsp;
+    </td>
+    <td width="3%" align="right">
+      &nbsp;
+    <td valign="top">
+      3.
+    </td>
+    <td width="41%">
+      With a long, branched, stalk
+    </td>
+    <td valign="top">
+      Genus <i>Codonocladium</i>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      &nbsp;
+    </td>
+    <td valign="top">
+      b.
+    </td>
+    <td colspan="3">
+      Free-swimming
+    </td>
+    <td valign="top">
+      Genus <i>Desmarella</i>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      4.
+    </td>
+    <td valign="top" colspan="4">
+      Colonial, and with a gelatinous covering
+    </td>
+    <td valign="top">
+      Genus <i>Proterospongia</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="6" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+<br><a name="Heteromastigida"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to families and marine genera of Heteromastigida.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Two flagella nearly equal in size
+    </td>
+    <td valign="top">
+      Family <i>Bodonidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      One main and 2 accessory flagella
+    </td>
+    <td valign="top">
+      Family <i>Trimastigidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2">
+      Family <i>Bodonidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Body very plastic, almost amœboid
+    </td>
+    <td valign="top">
+      Genus *<a href="#Bodo"><i>Bodo</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Body not plastic; with large anterior cavity, holding flagella
+    </td>
+    <td valign="top">
+      Genus *<a href="#Oxyrrhis"><i>Oxyrrhis</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2">
+      Family <i>Trimastigidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      With an undulatory membrane between accessory flagella
+    </td>
+    <td valign="top">
+      Genus <i>Trimastix</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Without such membrane; flagella contained in a ventral groove
+      while at rest
+    </td>
+    <td valign="top">
+      Genus <i>Costia</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+
+
+<br><a name="Polymastigida"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to marine genera of Polymastigida</i>.</b>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Body flattened; ends rounded; sides hollowed; often with
+      wing-like processes; cross section S-shaped
+    </td>
+    <td valign="top">
+      Genus <i>Trepomonas</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      Body pyriform; one large asymmetrical groove; 4 flagella
+    </td>
+    <td valign="top">
+      Genus <i>Tetramitus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="55%" valign="top">
+      Body spherical; many flagella equally distributed
+    </td>
+    <td valign="top">
+      Genus <i>Multicilia</i>
+    </td>
+  </tr>
+</table>
+<br><a name="Euglenida"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to families and marine genera of Euglenida.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      With deeply-insunk pharynx; no mouth
+    </td>
+    <td valign="top">
+      2
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      With pharynx and distinct mouth
+    </td>
+    <td valign="top">
+      Family <i>Peranemidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2
+    </td>
+    <td width="55%" valign="top">
+      Body plastic; usually with chromatophores and eye-spot
+    </td>
+    <td valign="top">
+      Family <i>Euglenidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Body plastic; no chromatophores; no eye-spot
+    </td>
+    <td valign="top">
+      Family <i>Astastidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2">
+      Family <i>Euglenidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Body <i>Euglena</i>-like, inclosed in shell with round
+      opening for exit of flagellum
+    </td>
+    <td valign="top">
+      Genus <i>Trachelomonas</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2">
+      Family <i>Astastidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Body with one flagellum
+    </td>
+    <td valign="top">
+      Genus *<a href="#Astasia"><i>Astasia</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2">
+      Family <i>Peranemidæ</i>:
+    </td>
+    <td valign="top">
+      &nbsp;
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Body striped; plastic; two diverse flagella
+    </td>
+    <td valign="top">
+      Genus <i>Heteronema</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      Body striped; not plastic; posterior flagellum longer
+      than the other
+    </td>
+    <td valign="top">
+      Genus *<a href="#Anisonema"><i>Anisonema</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="55%" valign="top">
+      Body striped; not plastic; with rod-like organ in
+      pharynx
+    </td>
+    <td valign="top">
+      Genus <i>Entosiphon</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+<br>
+<br>
+<a name="Mastigamoeba"></a>
+<br>
+<h3>Genus MASTIGAM&OElig;BA F. E. Schultze '75.</h3>
+
+<div class="center"><span class="syn">(Kent '81; B&uuml;tschli '86;
+Klebs '92; Senn 1900.)</span></div>
+
+<p>In general the form is oval and either regular in outline or
+irregular through the presence of many pseudopodia. One flagellum
+usually quite large and distinct. Differentiation of ectoplasm and
+endoplasm distinct or wanting. One to several contractile vacuoles.
+The pseudopodia are occasionally withdrawn, and the flagellum is the
+sole means of locomotion. In some cases the flagellum turns into a
+pseudopodium, and, conversely, the pseudopodium at one end may become
+a flagellum (see below). In some rare cases the ectoplasm secretes a
+gelatinous mantle. Reproduction not observed.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Mastigamoeba simplex"></a>
+<br >
+<p class="noindent"><b>Mastigamœba simplex,</b> n. sp.  Fig. 7.</p>
+
+<p>A very small form, first seen in the flagellated stage, aroused my
+interest by reason of the fact that its flagellum lost its regular
+outline and became amœboid, turning to a pseudopodium, while at the
+same time other pseudopodia were protruded from different parts of
+the periphery. In this condition ectoplasm and endoplasm could be
+made out with the clearest definition. After the pseudopodia were
+well formed, the body became flat and closely attached to the glass
+slide. In a short time one of the pseudopodia became longer than the
+rest; the body became more swollen; the pseudopodia were gradually
+drawn in, with the exception of the more elongate one; this became
+active in movement and finer in diameter, until ultimately it formed
+a single flagellum at the anterior of a small monadiform flagellate.
+The process was repeated two or three times under my observation, so
+that I am convinced that it was not a developmental form of some
+rhizopod. Several of them were seen at different times during the
+summer, and they were always of the same size and form in the
+flagellated or amœboid condition. I did not make out their
+reproduction, and I shall not be satisfied that this is a good
+species until their life history is known.</p>
+
+<p>In decaying algæ. Length 10&micro;.</p>
+
+<table class="imagetable" align="center"><tr><td>
+<center>
+<a href="images/fig_07.jpg">
+<img src="images/fig_07t.jpg" width="350" border=0
+alt="Mastigamoeba simplex"></a>
+<br>
+<b>Fig. 7.&mdash;<i>Mastigamœba simplex</i>.</b>
+<br>
+<br>
+<a href="images/fig_07.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<br>
+<br>
+<a name="Codonoeca"></a>
+<br>
+<h3>Genus CODON&OElig;CA James Clark '66.</h3>
+
+<p>(Kent '81.)</p>
+
+<p>Small forms inclosed in cup or "house" of ovoid or goblet shape,
+colorless and probably gelatinous (chitin?) in texture, and borne
+upon a stalk. The monad does not completely fill the test.
+Contractile vacuole single, posterior.</p>
+
+
+<a name="Codonoeca_gracilis"></a>
+<br >
+<p class="noindent"><b>Codonœca gracilis,</b> n. sp.  Fig. 8.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_08.jpg">
+<img src="images/fig_08t.jpg" width="190" border=0
+alt="Codonoecea gracilis"></a>
+<br>
+<b>Fig. 8.&mdash;<br>
+<i>Codonœcea gracilis</i>.</b>
+<br>
+<br>
+<a href="images/fig_08.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The cup is urn-shaped with a well-defined neck or collar borne upon a
+shoulder-like end of the body. It is hyaline, colorless, and carried
+upon a stalk equal in length to the cup or shorter than this. The
+animal does not fill the cup, nor is it attached by a filament to the
+latter. There is a single flagellum. The nucleus is minute and
+lateral in position; the contractile vacuole is in the posterior end
+of the body. Total length of cup and stalk 21&micro;; of cup alone 12&micro;.
+This minute form looked so much like a choanoflagellate that I
+supposed it to be one until I discovered an empty case (Fig. 8).</p>
+
+
+<br>
+<br>
+<a name="Monas"></a>
+<br>
+<h3>Genus MONAS (Ehr.) Stein '78</h3>
+
+<div class="center"><span class="syn">(Kent '81; B&uuml;tschli '86;
+Klebs '97; Senn 1900.)</span></div>
+
+<p>The body is small, globular or oval and either free-swimming or
+fastened by one of the two flagella. The body is sometimes a little
+amœboid, with short pseudopodial processes. In addition to the main
+flagellum, there are usually one or two small flagella at the basis
+of the larger one.  The nucleus is usually anterior, and one or two
+contractile vacuoles are present.</p>
+
+
+<table class="imagetable" align="right" width="100"><tr><td>
+<center>
+<a href="images/fig_09.jpg">
+<img src="images/fig_09.jpg" width="95" border=0
+alt="Monas sp."></a>
+<b>Fig. 9.&mdash;<br>
+<i>Monas</i> sp.</b>
+<br>
+<a href="images/fig_09.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<a name="Monas_sp"></a>
+<br>
+<p class="noindent"><b>Monas sp.</b>  Fig. 9.</p>
+
+<p>An extremely small form (3&micro;) attached by a thread of
+protoplasm&mdash;perhaps a flagellum, to algæ. The body is ovoid and the
+main flagellum is about four times the length of the body. The
+contractile vacuole is posterior. Only one specimen was seen and upon
+this I shall not attempt to name the species.</p>
+
+
+<br>
+<br><a name="Monosiga"></a>
+<br>
+<h3>Genus MONOSIGA Kent '81.</h3>
+
+<div class="center"><span class="syn">(B&uuml;tschli '86;
+Franc&eacute; '97; Senn 1900.)</span></div>
+
+<p>Small colorless forms of Choanoflagellida, always naked and solitary.
+The posterior end is attached directly to the substratum, or there is
+a short stalk not exceeding the body in length. Kent '81
+distinguished nine species, but B&uuml;tschli questioned the accuracy of
+many of these, and in this he was followed by Franc&eacute; '97, who
+recognized three species&mdash;<i>Monosiga ovata</i>, <i>M. fusiformis</i>, and <i>M.
+augustata</i>. Fresh and salt water.</p>
+
+
+
+<table class="imagetable" align="right" width="100"><tr><td>
+<center>
+<a href="images/fig_10.jpg">
+<img src="images/fig_10t.jpg" width="80" border=0
+alt="Monosiga ovata"></a>
+<b>Fig. 10.&mdash;<br>
+<i>Monosiga ovata</i>.</b>
+<br>
+<a href="images/fig_10.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<a name="Monosiga_ovata"></a>
+<br>
+<p class="noindent"><b>Monosiga ovata</b> S. Kent '81.  Fig. 10.</p>
+
+<p class="syn">Synonyms: <i>M. brevipes</i> S. K.; <i>M. consociata</i> S. K.; <i>M. limnobia</i>
+Stokes.</p>
+
+<p>The individuals are unstalked or provided with a very short stalk
+less than the body in length. The form is spherical or ovate,
+broadest at the base and tapering to the extremity. The collar is
+somewhat variable in size. In the Woods Hole forms it was about the
+length of the body. Oil particles present. Contractile vacuole
+posterior, nucleus anterior.</p>
+
+<p>Fresh and salt water. Length of body without the collar 5&micro;.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_11.jpg">
+<img src="images/fig_11.jpg" width="60" border=0
+alt="Monosiga fusiformis"></a>
+<br>
+<b>Fig. 11.&mdash;<br>
+<i>Monosiga<br>fusiformis</i>.</b>
+<br>
+<a href="images/fig_11.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<a name="Monosiga_fusiformis"></a>
+<br>
+<p class="noindent"><b>Monosiga fusiformis</b> S. K.  Fig. 11.</p>
+
+<p class="syn">Synonyms: <i>M. steinii</i> S. K.;
+<i>M. longicollis</i> S. K.</p>
+
+<p>The individuals are unstalked, minute, and of a general flask-shape.
+The body is swollen centrally and tapers slightly at each end. There
+is no stalk, the body being fixed by the attenuate posterior end.
+There are two contractile vacuoles and one nucleus, which is situated
+a little above the body center. Fresh and salt water. Length without
+collar 9&micro;; length of collar 3&micro;.</p>
+
+
+
+<br>
+<br><a name="Codonosiga"></a>
+<br>
+<h3>Genus CODONOSIGA (Jas. Clark '67).</h3>
+
+<div class="center"><span class="syn">(B&uuml;tschli '78; Kent '81;
+Franc&eacute; '97; Senn 1900.)</span></div>
+
+<p>This genus, as modified by Franc&eacute;, is distinguished from the
+preceding by the possession of an unbranched stalk much longer than
+the body length. The body is naked and of various shapes, and the
+individuals are solitary or colonial upon a single stalk. Kent '81
+enumerates no less than 10 species, which were cut down by B&uuml;tschli
+to 1. Franc&eacute; admits 4&mdash;<i>C. botrytis</i> Jas. Clark; <i>C. grossularia</i>;
+<i>C. pyriformis</i>, and <i>C. furcata</i>, all S. Kent&mdash;but regards the
+second and third as merely form varieties of the first.</p>
+
+
+<table class="imagetable" align="right" width="100"><tr><td>
+<center>
+<a href="images/fig_12.jpg">
+<img src="images/fig_12.jpg" width="95" border=0
+alt="Codonosiga botrytis"></a>
+<b>Fig. 12.&mdash;<br>
+<i>Codonosiga botrytis</i>.</b>
+<br>
+<a href="images/fig_12.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<a name="Codonosiga_botrytis"></a>
+<br >
+<p class="noindent"><b>Codonosiga botrytis</b>
+(Ehr. sp.) Jas. Clark '67.  Fig. 12.</p>
+
+<p class="syn">Franc&eacute; gives the following synonyms: <i>Epistylia botrytis</i> Ehr.; <i>E.
+digitalis</i> Stein, <i>Zoothamnium parasitica</i> Stein; <i>Anthophysa
+solitaria</i> Fresenius; <i>Codonosiga pulcherrima</i> Jas. Clark; <i>Monosiga
+gracilis</i> S. Kent; <i>M. globulosa</i> S. Kent; <i>Codonosiga pyriformis</i>
+Kent; <i>C. grossularia</i> Kent; (Franc&eacute;).</p>
+
+<p>The individuals are small and provided with a long unbranched, or
+terminal, simply split stalk. The individuals are single or colonial.
+The Woods Hole form measured 22&micro; over all; the body was 5&micro;, the
+collar 3&micro;, and the stalk 14&micro;. No colonies were seen, and only a few
+individuals upon red algæ.</p>
+
+
+<br>
+<br><a name="Bodo"></a>
+<br>
+<h3>Genus BODO (Ehr.) Stein.</h3>
+
+<div class="center"><span class="syn">(Stein '59, B&uuml;tschli '83;
+Klebs '92; Senn 1900.)</span></div>
+
+<p>The body is naked, usually amœboid in its changes, and provided with
+two flagella, one of which is usually trailed along under and behind
+the animal. The anterior end is usually pointed, with the flagella
+arising from a minute depression; the posterior end is rounded.
+Specific characters very difficult to analyze. Fresh and salt water.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_13.jpg">
+<img src="images/fig_13t.jpg" width="60" border=0
+alt="Bodo globosus"></a>
+</center>
+</td><td>
+<center>
+<b>Fig. 13.&mdash;<br>
+<i>Bodo globosus</i>.</b>
+<br>
+<br>
+<a href="images/fig_13.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<a name="Bodo_globosus"></a>
+<br>
+<p class="noindent"><b>Bodo globosus</b> Stein.  Fig. 13.</p>
+
+<p>The body during movement is globular or ovoid, without any anterior
+process. The trailing flagellum is invariably much longer than the
+vibratory one. The contractile vacuole lies in the anterior half of
+the body. Solid food particles are taken in near base of flagella.</p>
+
+<p>Length of body 9 to 12&micro;; diameter 8 to 11&micro;. Common.</p>
+
+
+<a name="Bodo_caudatus"></a>
+<br>
+<p class="noindent"><b>Bodo caudatus</b> (Duj.) Stein.  Fig. 14.</p>
+
+<p class="syn">Synonyms: <i>Amphimonas caudatus</i> Duj.;
+<i>Diptomastix caudata</i> Kent.</p>
+
+<p>The body is variable in shape, but usually flattened and pointed
+posteriorly. An anterior process is almost always present, and below
+this the flagella are inserted in a minute depression. The
+contractile vacuole is close to the base of the flagella. The
+flagella are about the same size, the anterior one usually somewhat
+longer. Common. Length 12 to 18&micro;.</p>
+
+<p>This species was seen by Peck '95 and described as a small
+flagellate.</p>
+
+
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_14.jpg">
+<img src="images/fig_14t.jpg" width="260" border=0
+alt="Bodo caudatus"></a>
+</td><td align="center">
+<b>Fig. 14.&mdash;<i>Bodo caudatus</i>.</b>
+<br>
+<br>
+<a href="images/fig_14.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr></table>
+
+
+<br>
+<br><a name="Oxyrrhis"></a>
+<br>
+<h3>Genus OXYRRHIS Duj.</h3>
+
+<div class="center"><span class="syn">(Kent '81; B&uuml;tschli '86;
+Klebs '92; Senn 1900.)</span></div>
+
+<p>Medium-sized forms, somewhat oval in shape, with a rounded posterior
+end. The anterior end is continued dorsally in a somewhat attenuate
+pointed process. At the base of this process is a large cavity or
+funnel, on the dorsal wall of which, or on a projection from this
+wall, are two equal-size flagella. When at rest, the flagella are
+directed backwards. The nucleus is central. In moving, the posterior
+end is invariably in advance. This genus is exceptional among
+Mastigophora in that division is transverse instead of longitudinal.</p>
+
+
+<a name="Oxyrrhis_marina"></a>
+<br >
+<p class="noindent"><b>Oxyrrhis marina</b> Duj.  Fig. 15.</p>
+
+<p>With the characters of the genus. Contractile vacuole not seen.
+Length 28 to 40&micro;.</p>
+
+
+<table class="imagetable" align="center"><tr><td>
+<center>
+<a href="images/fig_15.jpg">
+<img src="images/fig_15t.jpg" width="200" border=0
+alt="Oxyrrhis marina"></a>
+</center>
+</td><td>
+<center>
+<b>Fig. 15.&mdash;<br>
+<i>Oxyrrhis marina</i>.</b>
+<br>
+<br>
+<a href="images/fig_15.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<br>
+<br><a name="Astasia"></a>
+<br>
+<h3>Genus ASTASIA Ehr.</h3>
+
+<p>Flagellates with one flagellum, a spindle-form body and a high degree
+of plasticity, the contour constantly changing. A distinct, usually
+striped cuticle is invariably present. "Eye-spots" are absent. Fresh
+and salt water.</p>
+
+
+<a name="Astasia_contorta"></a>
+<br >
+<p class="noindent"><b>Astasia contorta</b> Duj.  Fig. 16.</p>
+
+<p class="syn"><i>Astasia inflata</i> Duj. '41.</p>
+
+<p>The body is colorless, transparent, and flexible. It is largest in
+the center, thence tapering at the two extremities. The surface of
+the cuticle is obliquely striated, giving to the animal a distinctly
+twisted appearance. The contractile vacuole is in the anterior
+neck-like portion of the body. The flagellum is inserted in a
+distinct Å“sophageal tube, into which the contractile vacuole
+empties. This tube is continued into a deeper pharyngeal apparatus of
+unknown function.</p>
+
+<p>Common in decaying algæ. Length 60&micro;; greatest diameter 30&micro;.</p>
+
+
+<table class="imagetable" align="center"><tr><td>
+<center>
+<a href="images/fig_16.jpg">
+<img src="images/fig_16t.jpg" width="310" border=0
+alt="Two aspects of Astasia contorta"></a>
+<br>
+<b>Fig. 16.&mdash;Two aspects of <i>Astasia contorta</i>.</b>
+<br>
+<br>
+<a href="images/fig_16.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<br>
+<br><a name="Anisonema"></a>
+<br>
+<h3>Genus ANISONEMA B&uuml;tschli</h3>
+
+<p>Flagellates with two flagella, of which one is directed forwards and
+is concerned with the locomotion of the animal, while the other is
+directed backwards and drags after the animal when in motion. Body
+slightly compressed dorso-ventrally (fig. 17, section). An oral
+furrow is present on the ventral side and the two flagella originate
+in it (fig. 17, at left). The vacuole is on the left side. Food
+vacuoles are present in the posterior part. The nucleus is central.
+Movement creeping.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Anisonema_vitrea"></a>
+<br >
+<p class="noindent"><b>Anisonema vitrea</b> (Duj.)  Fig. 17.</p>
+
+<p class="syn">Synonyms: <i>Tropidoscyphus octocostatus</i> Stein '83; <i>Sphenomonas</i> Kent
+'81; <i>Plœotia vitrea</i> Senn 1900.</p>
+
+<p>With the characteristics of the genus. It differs from freshwater
+forms in having eight furrowed surfaces running somewhat spirally
+from the posterior to the oral end. Length 50&micro;; width 23&micro;.  This
+attractive flagellate was quite common in decaying algæ at Woods
+Hole; its shaking movement, its peculiar furrowed surfaces, and,
+above all, its perfectly transparent, vitreous appearance, were well
+described by Dujardin. Stein's <i>Tropidoscyphus octocostatus</i> is a
+fresh-water form which may possibly be a distinct species, especially
+as it is described with both flagella directed forwards.</p>
+
+
+<table class="imagetable" align="center"><tr><td>
+<center>
+<a href="images/fig_17.jpg">
+<img src="images/fig_17t.jpg" width="490" border=0
+alt="Anisonema vitrea"></a>
+<br>
+<b>Fig. 17.&mdash;<i>Anisonema vitrea</i>.</b>
+<br>
+<br>
+<a href="images/fig_17.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<br>
+<br><a name="Distephanus"></a>
+<br>
+<h3>Genus DISTEPHANUS  Stöhr.</h3>
+
+<p>An aberrant flagellate bearing a single flagellum and a silicious
+skeleton resembling those of the Radiolaria. The skeleton consists of
+two rings of different diameter parallel with one another and
+connected by silicious bars. From the wider ring half a dozen bars
+radiate outwards and a similar number of short thorn-like bars point
+inwards obliquely. The color is yellow, and except for the flagellum
+the form might easily be mistaken for a Radiolarian, as has been the
+case repeatedly.</p>
+
+
+<a name="Distephanus_speculum"></a>
+<br >
+<p class="noindent"><b>Distephanus speculum</b> Stöhr.</p>
+
+<p class="syn"><i>Dictyocha speculum</i> Stöhr; <i>Dictyocha</i> Auc.</p>
+
+<p>With the characters of the genus.</p>
+
+<p>A single specimen only of this very interesting form was seen at
+Woods Hole. It occurred in a collection of tow made near the end of
+the wharf during the evening.</p>
+
+
+<br><a name="Dinoflagellidia"></a>
+<br>
+<center>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to families of Dinoflagellidia.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      No crossfurrow; two free flagella
+    </td>
+    <td valign="top">
+      Family <a href="#Prorocentridae"><i>Prorocentridæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      One or more cross-furrows
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="55%" valign="top">
+      Cross-furrow nearly central (cf. <i>Oxytoxum</i>)
+    </td>
+    <td valign="top">
+      Family <a href="#Peridinidae"><i>Peridinidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Cross-furrow close to anterior end
+    </td>
+    <td valign="top">
+      Family <a href="#Dinophysidae"><i>Dinophysidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Several cross-furrows and flagella
+    </td>
+    <td valign="top">
+      Family <i>Polydinidæ</i><br>
+      (One genus,<br>
+      <i>Polykrikos</i>.)
+    </td>
+  </tr>
+</table>
+<br><a name="Prorocentridae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to marine genera of Prorocentridæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      <i>Diagnostic characters:</i> The transverse furrow is
+      absent and the two flagella arise from the anterior end
+      of the body. The shell may be bivalved.
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      No tooth-like process dorsal to the flagellum
+    </td>
+    <td valign="top">
+      Genus *<a href="#Exuviaella"><i>Exuviælla</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      With tooth-like process dorsal to the flagellum
+    </td>
+    <td valign="top">
+      Genus <i>Prorocentrum</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+<br><a name="Peridinidae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to marine genera of Peridinidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      <i>Diagnostic characters:</i> The cross-furrow is nearly
+      central (see, however, <i>Oxytoxum</i>); the body may or
+      may not have a shell; the shell may or may not be composed
+      of distinct plates; the plates are distinguished as
+      <i>equatorial</i> (<i>i.e.</i>, bordering the cross-furrow),
+      <i>apical</i>, and <i>antapical</i>, while still another,
+      the "rhombic plate", may be present, extending from the
+      cross-furrow to the apex.
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Without distinct shell
+    </td>
+    <td valign="top">
+      Genus *<a href="#Gymnodinium"><i>Gymnodinium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      With a distinct shell
+    </td>
+    <td valign="top">
+      2
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      Shell not composed of definite plates
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Shell composed of definite plates
+    </td>
+    <td valign="top">
+      4.
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="55%" valign="top">
+      Cross-furrow replaced by thin-skinned band
+    </td>
+    <td valign="top">
+      Genus <i>Ptychodiscus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Cross-furrow well defined; reticulate markings raised
+      on shell-surface
+    </td>
+    <td valign="top">
+      Genus <i>Protoceratium</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Cross-furrow well defined; no markings
+    </td>
+    <td valign="top">
+      Genus *<a href="#Glenodinium"><i>Glenodinium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      4.
+    </td>
+    <td width="55%" valign="top">
+      Two parts of shell equal or nearly equal
+    </td>
+    <td valign="top">
+      5
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Two parts of shell very unequal
+    </td>
+    <td valign="top">
+      11
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      5.
+    </td>
+    <td width="55%" valign="top">
+      With transverse flagellum in a distinct furrow
+    </td>
+    <td valign="top">
+      6
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Transverse flagellum not in a furrow
+    </td>
+    <td valign="top">
+      10
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      6.
+    </td>
+    <td width="55%" valign="top">
+      With horns, or with wing-like processes
+    </td>
+    <td valign="top">
+      7
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Without processes of any kind kind
+    </td>
+    <td valign="top">
+      9
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      7.
+    </td>
+    <td width="55%" valign="top">
+      Processes small, wing-like, around flagellum-fissure
+    </td>
+    <td valign="top">
+      Genus <i>Diplopsalis</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Processes horn-like
+    </td>
+    <td valign="top">
+      8
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      8.
+    </td>
+    <td width="55%" valign="top">
+      Anterior part with 7 equatorial and 1 rhombic plates
+    </td>
+    <td valign="top">
+      Genus *<a href="#Peridinium"><i>Peridinium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Anterior part with 5 equatorial and no rhombic plates
+    </td>
+    <td valign="top">
+      Genus <i>Gonyaulax</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Anterior part with 3 equatorial and no rhombic plates
+    </td>
+    <td valign="top">
+      Genus *<a href="#Ceratium"><i>Ceratium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      9.
+    </td>
+    <td width="55%" valign="top">
+      Anterior part with 14 equatorial and 1 rhombic plates
+    </td>
+    <td valign="top">
+      Genus <i>Pyrophacus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Anterior part with 7 equatorial plates
+    </td>
+    <td valign="top">
+      Genus <i>Goniodoma</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Anterior part with 4 equatorial plates
+    </td>
+    <td valign="top">
+      Genus <i>Amphidoma</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      10.
+    </td>
+    <td width="55%" valign="top">
+      Apical extremity drawn out into a tube
+    </td>
+    <td valign="top">
+      Genus <i>Podolampas</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      pical extremity not drawn out into a tube
+    </td>
+    <td valign="top">
+      Genus <i>Blepharocysta</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      11.
+    </td>
+    <td width="55%" valign="top">
+      Cross-furrow deep, with great ledge-like walls
+    </td>
+    <td valign="top">
+      Genus <i>Ceratocorys</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Cross-furrow wide, no ledge-like walls
+    </td>
+    <td valign="top">
+      Genus <i>Oxytoxum</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+<br><a name="Dinophysidae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to marine genera of Dinophysidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      <i>Diagnostic characters:</i> The cross-furrow is above the
+      center of the body, and its edges, as well as the left edge
+      of the longitudinal furrow, are usually produced into
+      characteristic ledges; those of the cross-furrow usually
+      form great funnel-like anterior processes, while those of
+      the longitudinal furrow usually form great, lateral,
+      wing-like processes ornamented by ribs and other markings.
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td width="55%" valign="top">
+      Without shell; longitudinal furrow may open &amp; close
+    </td>
+    <td valign="top">
+      Genus *<a href="#Amphidinium"><i>Amphidinium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td width="55%" valign="top">
+      With shell; longitudinal furrow unchangeable
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="55%" valign="top">
+      With distinct apical funnel
+    </td>
+    <td valign="top">
+      4
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      No apical funnel
+    </td>
+    <td valign="top">
+      Genus <i>Phalacroma</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      4.
+    </td>
+    <td width="55%" valign="top">
+      With great wing-like ledge
+    </td>
+    <td valign="top">
+      5
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Ledges very small; body long, needle-like
+    </td>
+    <td valign="top">
+      Genus <i>Amphisolenia</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      5.
+    </td>
+    <td width="55%" valign="top">
+      Ledge of longitudinal furrow extends to posterior end
+    </td>
+    <td valign="top">
+      6
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Ledge of longitudinal furrow does not extend to posterior
+      end<br>
+      (Recorded by Peck ('93-'95) as very abundant at Woods Hole
+      and in Buzzards Bay.)
+    </td>
+    <td valign="top">
+      Genus <i>Dinophysis</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      6.
+    </td>
+    <td width="55%" valign="top">
+      Ledge is continued dorsally to the cross-furrow
+    </td>
+    <td valign="top">
+      Genus <i>Ornithocercus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Ledge is not continued dorsally
+    </td>
+    <td valign="top">
+      7
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      7.
+    </td>
+    <td width="55%" valign="top">
+      With deep dorsal cavity; secondary funnel not notched
+    </td>
+    <td valign="top">
+      Genus <i>Citharistes</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      No dorsal cavity; secondary funnel deeply notched
+    </td>
+    <td valign="top">
+      Genus <i>Histioneis</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+<br>
+<br><a name="Exuviaella"></a>
+<br>
+<h3>Genus EXUVI&AElig;LLA Cienkowsky '82.</h3>
+
+<div class="center"><span class="syn">(Klebs '81; Pouchet '83,
+'86.)</span></div>
+
+<p>The form varies from globular to ovoid, with occasionally a sharp
+posterior end. Shells are usually somewhat compressed, and consist of
+two valves, which frequently slide one over the other in such a
+manner as to show the structure with great clearness. The right shell
+may have a distinct indentation in the anterior edge. There are two
+lateral, discoid, brown chromatophores, each of which possesses a
+central amylum granule. The nucleus is posterior. Salt water.</p>
+
+
+<a name="Exuviaella_lima"></a>
+<br>
+<p class="noindent"><b>Exuviælla lima</b> Ehr.  Fig. 18.</p>
+
+
+<p class="syn">Synonyms <i>Pyxidicula</i> Ehr.; <i>Cryptomonas</i>
+Ehr.; <i>Prorocentrum lima</i> Kent; <i>Amphidinium</i> Pouchet.</p>
+
+<p>The shell is ovate, rounded and swollen posteriorly. The anterior
+border of both shells is slightly indented. The shell is quite thick.
+The animal moves through the water very slowly. Dark brown in color.
+Length 48&micro;; width 44&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_18.jpg">
+<img src="images/fig_18t.jpg" width="250" border=0
+alt="Exuviaella lima"></a>
+</td><td align="center">
+<b>Fig. 18.&mdash;<br>
+<i>Exuviælla<br>lima</i>.</b>
+<br>
+<br>
+<a href="images/fig_18.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Exuviaella_marina"></a>
+<br>
+<p class="noindent"><b>Exuviælla marina</b> Cienkowsky.  Fig. 19.</p>
+
+<p>A smaller form than the preceding, more elliptical in outline, with a
+thinner shell and with large granules throughout the endoplasm. The
+nucleus is spherical and subcentral in position and possesses a
+distinct central granule. This may be a small variety of <i>E. lima</i>.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_19.jpg">
+<img src="images/fig_19t.jpg" width="200" border=0
+alt="Exuviaella marina"></a>
+</td><td align="center">
+<b>Fig. 19.&mdash;<br>
+<i>Exuviælla marina</i>.</b>
+<br>
+<br>
+<a href="images/fig_19.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+<br>
+<br><a name="Gymnodinium"></a>
+<br>
+<h3>Genus GYMNODINIUM Stein '78.</h3>
+
+<div class="center"><span class="syn">(Bergh '81; Kent '81; Pouchet
+'83, '85; Entz '84; Sch&uuml;tt '95.)</span></div>
+
+<p>The general structure of these forms is similar to that of
+<a href="#Glenodinium1"><i>Glenodinium</i></a>; the most
+striking and positive difference is the
+absence of a shell. The animals are, as a rule, spherical, yet they
+may be pointed at the two ends or at one of them. They are also
+frequently flattened dorso-ventrally. The transverse furrow may be
+either circular and straight around the body or may describe a spiral
+course, passing even twice around the body. The flagella arise near
+cross-furrow or, in some cases, in longitudinal furrow.
+Chromatophores may or may not be present and food-taking is holozoic,
+in many cases at least. In some cases ectoplasm and endoplasm can be
+distinguished. Fresh and salt water.</p>
+
+
+<a name="Gymnodinium_gracile"></a>
+<br>
+<p class="noindent"><b>Gymnodinium gracile</b> Bergh '82,
+var. sphærica, n.  Fig. 20.</p>
+
+<p>The body is divided by the transverse furrow into a shorter anterior
+and a longer posterior part. The longitudinal furrow is broader at
+the posterior extremity than at the cross-furrow. The structural
+feature upon which this new variety is made is the unvarying
+plumpness of the body, making it almost spherical, except for a
+slight flattening dorso-ventrally. The nucleus is large and
+ellipsoidal, with characteristic longitudinal markings of chromatin.
+The endoplasm is evenly granular, with a number of large ingested
+food bodies. The color is brown, not rose-red as in Bergh's species,
+nor is the Woods Hole form as large as the latter. Length of body
+68&micro;; width 55&micro;. Common.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_20.jpg">
+<img src="images/fig_20t.jpg" width="250" border=0
+alt="Gymnodinium gracile,
+var. sphaerica"></a>
+</td><td align="center">
+<b>Fig. 20.&mdash;<br>
+<i>Gymnodinium gracile</i>,<br>
+var. <i>sphærica</i>.</b>
+<br>
+<br>
+<a href="images/fig_20.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Glenodinium"></a><a name="Glenodinium1"></a><a
+name="Glenodinium2"></a>
+<br>
+<h3>Genus GLENODINIUM (Ehr.), Stein '83.</h3>
+
+<div class="center"><span class="syn">(Bergh '82; B&uuml;tschli
+'86; Pouchet '85; Daday '86.)</span></div>
+
+<p>Small globular forms with two distinct furrows, one transverse around
+the body, the other longitudinal upon the face only. The shell is
+soft and structureless with a distinct aperture near the meeting
+point of the two furrows. The endoplasm usually, but not always,
+contains a bright red eye-spot.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Glenodinium_compressa"></a>
+<br>
+<p class="noindent"><b>Glenodinium compressa</b>, n. sp.
+Fig. 21, a, b, c.</p>
+
+<p>This species resembles <i>G. acuminata</i> of Ehrenberg except that it is
+strongly compressed laterally. The longitudinal furrow extends nearly
+to the extremity of the animal. It begins as a narrow slit and widens
+as it progresses upon the left side; it also becomes much deeper on
+this side and at the bottom of the depression the longitudinal
+flagellum is inserted. The transverse furrow runs evenly around the
+body near the upper pole, giving to the shell almost the aspect of an
+<a href="#Amphidinium1"><i>Amphidinium</i></a>. Brown
+chromatophores may or may not be arranged
+radially about a central amylum granule. One striking characteristic
+is the depth of the two furrows. The nucleus is elongate and somewhat
+curved; it lies against the posterior wall of the rather thick shell.
+Not uncommon.</p>
+
+<p>Length 40&micro;; breadth 32&micro;; width 18&micro;.</p>
+
+<p>The posterior end of the animal is often somewhat pointed and this
+point frequently becomes attached, so that the animal whirls around
+upon it as upon a pivot.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_21.jpg">
+<img src="images/fig_21t.jpg" width="450" border=0
+alt="Glenodinium compressa, n. sp."></a><br>
+<b>Fig. 21 a, b, c.&mdash;<i>Glenodinium compressa</i>, n. sp.</b>
+<br>
+<br>
+<a href="images/fig_21.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Glenodinium_cinctum"></a>
+<br>
+<p class="noindent"><b>Glenodinium cinctum</b> Ehr.  Fig. 22.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_22.jpg">
+<img src="images/fig_22t.jpg" width="150" border=0
+alt="Glenodinium cinctum"></a>
+<br>
+<b>Fig. 22.&mdash;<br>
+<i>Glenodinium cinctum</i>.</b>
+<br>
+<a href="images/fig_22.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The body is globular, smooth, and homogeneous.  Brown chromatophores
+arranged radially, each in the form of a cone, the base of which
+rests against the shell while the points turn inward.  A bright-red
+eye-spot may or may not be present; when present it is placed near
+the junction of the two furrows. The longitudinal furrow is small.
+Fresh water and salt.</p>
+
+<p>Length and diameter the same, 21&micro;.</p>
+
+<p>This species was observed by Peck '93.</p>
+
+
+<p>[Illustration: Fig. 22.&mdash;<i>Glenodinium cinctum</i>.]</p>
+
+
+<br>
+<br><a name="Peridinium"></a>
+<br>
+<h3>Genus PERIDINIUM Ehr. '32, Stein '83.</h3>
+
+<div class="center"><span class="syn">(Clapar&egrave;de &amp;
+Lachmann '58; Bergh '81; Pouchet '83; '85; Gourret '88;
+B&uuml;tschli '86.)</span></div>
+
+<p>The form is globular, ovoid or elongate, the apex frequently drawn
+out into a long tube. The transverse and longitudinal furrows are
+quite distinct, the former having often a spiral course about the
+body. The two halves of the body are similar, the posterior being
+somewhat shorter; the anterior half has seven equatorial plates, an
+oral plate, two lateral apical plates, and one or two dorsal plates.
+The two antapical plates frequently have a tooth-like process. The
+bodies are colorless, green or brown.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Peridinium_digitale"></a>
+<br>
+<p class="noindent"><b>Peridinium digitale</b> Pouchet.  Fig. 23.</p>
+
+<p class="syn">Synonyms: <i>Protoperidinium digitale</i> Pouchet;
+<i>Protoperidinium</i> Bergh p. p.; <i>P. divergens</i> Peck.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_23.jpg">
+<img src="images/fig_23t.jpg" width="200" border=0
+alt="Peridinium digitale"></a>
+<br>
+<b>Fig. 23.&mdash;<br>
+<i>Peridinium digitale</i>.</b>
+<br>
+<br>
+<a href="images/fig_23.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The shell is covered with pits of large size. The posterior part is
+hemispherical and surmounted by a single horn or spine. The
+transverse furrow is very oblique, and its two extremities are united
+by a sigmoid longitudinal furrow. The anterior half bears two spines
+or horns of different size, and variable.  The nucleus is spherical
+or ellipsoidal and placed in the posterior half of the shell.</p>
+
+<p>Length 68&micro;; diameter 54&micro;. Common.</p>
+
+<p>Although the description of Pouchet's <i>P. digitale</i> differs in some
+respects from a careful description of the Woods Hole form, I think
+the species are the same. The chief difference is in the single horn
+of the posterior half; in Pouchet's form this is furrowed by a narrow
+groove which runs to the S-shaped longitudinal furrow. In the Woods
+Hole form I was unable to make out such a furrow. The flagella, also,
+were not seen. This same form was pictured by Peck '95 as <i>P.
+divergens</i>.</p>
+
+
+<a name="Peridinium_divergens"></a>
+<br>
+<p class="noindent"><b>Peridinium divergens</b> Ehr.  Fig. 24.</p>
+
+<p class="syn">Synonym: <i>Ceratium divergens</i> Kent.</p>
+
+<p>The shell is spheroidal, widest centrally, attenuate and pointed
+posteriorly; the anterior portion is armed with two short, pointed
+horns, each of them having a toothed process at the basal portion of
+the inner margin. They are frequently colorless and beautifully
+transparent, the body being free from large opaque granules; again
+they are colored brown or yellow. The nucleus is large and elongate
+and finely granular. 75&micro; long and 68&micro; in diameter. Common.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_24.jpg">
+<img src="images/fig_24t.jpg" width="400" border=0
+alt="Ventral and dorsal aspects
+of Peridinium divergens"></a>
+<br>
+<b>Fig. 24.&mdash;Ventral and dorsal aspects of
+<i>Peridinium divergens</i>.</b>
+<br>
+<br>
+<a href="images/fig_24.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Ceratium"></a>
+<br>
+<h3>Genus CERATIUM (Schrank).</h3>
+
+<div class="center"><span class="syn">(Stein '78; Perty '52; Clap &amp;
+Lach. '58; Bergh '82; Pouchet '83;<br>
+Gourret &amp; Roeser '88; B&uuml;tschli '85; Kent '81;
+Senn 1900; Sch&uuml;tt '98.)</span></div>
+
+<p>The general shape is a flattened sphere with three long processes or
+horns. The cross-furrow is either spiral or circular; the
+longitudinal furrow is usually wide and occupies the greater part of
+the anterior half of the shell. The shell is thick, reticulate or
+striped, and sometimes provided with short spines; often distinctly
+porous. The anterior half is composed of 3 equatorial and 3 apical
+plates, the latter being continued into the horn-like process. The
+posterior half is composed of 3 equatorial and one apical plate
+continued into the posterior horn. The right posterior plate is
+continued into a similar horn which may remain rudimentary or be
+continued into a considerable process. Similarly the left posterior
+horn is usually developed, but remains small. There may be from 2 to
+3, 4, and 5 horns. Chromatophores usually present, green to yellow
+brown.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Ceratium_tripos"></a>
+<br>
+<p class="noindent"><b>Ceratium tripos</b> Ehr.  Fig. 25.</p>
+
+<p>The body is somewhat triangular and bears three horns, two of which
+are shorter than the other one and slightly curved upward.</p>
+
+<p>Length, including the horns, 290&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_25.jpg">
+<img src="images/fig_25t.jpg" width="550" border=0
+alt="Ceratium tripos"></a>
+<br>
+<b>Fig. 25.&mdash;<i>Ceratium tripos</i>.</b> &nbsp; &nbsp;
+<a href="images/fig_25.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Ceratium_fusus"></a>
+<br>
+<p class="noindent"><b>Ceratium fusus</b> Ehr.  Fig. 26.</p>
+
+<p class="syn">Synonym: <i>Peridinium fusus</i> Ehr.</p>
+
+<p>The animal is very elongate, due to the presence of two long horns at
+the extremities of the body. Color, yellow with chromatophores.
+Length 285&micro;; width 23&micro;.</p>
+
+<p>Both of these species are common in the tow and in the algæ at the
+edge of the wharf. Both of them are mentioned by Peck in '93 and '95.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_26.jpg">
+<img src="images/fig_26t.jpg" width="550" border=0
+alt="Ceratium fusus"></a>
+<br>
+<b>Fig. 26.&mdash;<i>Ceratium fusus</i>.</b>
+<br>
+<br>
+<a href="images/fig_26.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Amphidinium"></a><a name="Amphidinium1"></a><a name="Amphidinium2"></a>
+<br>
+<h3>Genus AMPHIDINIUM Clap. &amp; Lach.</h3>
+
+<p>The body is ovoid to globular and usually much flattened
+dorso-ventrally. The anterior portion is very much reduced and is
+somewhat head-like or cap-like. The longitudinal furrow extends
+through the entire posterior body length and is apparently capable of
+widening and narrowing. It is probably naked (see here Klebs,
+Pouchet, B&uuml;tschli), although Stein maintained that there is a
+delicate cuticle-like shell. Chromatophores of brown or green colors
+present and usually grouped radially about a central amylum granule.
+The nucleus is posterior.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Amphidinium_operculatum"></a>
+<br>
+<p class="noindent"><b>Amphidinium operculatum</b>
+Clap. &amp; Lach.  Fig. 27.</p>
+
+<p>The body is oval and flattened. The transverse furrow is at the
+extremity (posterior) of the body and the small portion, which is
+thus apparently cut off, is the cap-like or operculum-like structure
+which gives the name to the species. Klebs maintains that the two
+furrows are not connected, but in this he is certainly mistaken,
+provided we have the same species under consideration.  Very common
+about Woods Hole.</p>
+
+<p>Length from 40 to 50&micro;; width 30&micro;; thickness 15&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_27.jpg">
+<img src="images/fig_27t.jpg" width="250" border=0
+alt="Amphidinium operculatum"></a>
+</td><td align="center">
+<b>Fig. 27.&mdash;<br>
+<i>Amphidinium operculatum</i>.</b>
+<br>
+<br>
+<a href="images/fig_27.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br>
+<center>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="4" align="center">
+      <b><i>Key to Infusoria.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      1.
+    </td>
+    <td colspan="2" valign="top">
+      With cilia
+    </td>
+    <td valign="top">
+      Subclass <i>Ciliata</i>. 3
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      2.
+    </td>
+    <td colspan="2" valign="top">
+      Without cilia (in adult state) tentacles
+    </td>
+    <td valign="top">
+      Subclass <a href="#Suctoria2"><i>Suctoria</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="5%" valign="top" align="right">
+      a.
+    </td>
+    <td width="50%" valign="top">
+      Without a specialized fringe of large cilia (ad. zone)
+    </td>
+    <td valign="top">
+      Order <a href="#Holotrichida1"><i>Holotrichida</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      b.
+    </td>
+    <td width="50%" valign="top">
+      With general covering of cilia + adoral zone
+    </td>
+    <td valign="top">
+      Order <a href="#Heterotrichida1"><i>Heterotrichida</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      c.
+    </td>
+    <td width="50%" valign="top">
+      With cilia on ventral side + adoral zone
+    </td>
+    <td valign="top">
+      Order <a href="#Hypotrichida1"><i>Hypotrichida</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      d.
+    </td>
+    <td width="50%" valign="top">
+      With cilia in region of adoral zone, and about mouth only
+    </td>
+    <td valign="top">
+      Order <a href="#Peritrichida1"><i>Peritrichida</i></a>
+    </td>
+  </tr>
+</table>
+<br><a name="Holotrichida"></a><a name="Holotrichida1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="5" align="center">
+      <b><i>Key to families of the Holotrichida.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      A.
+    </td>
+    <td colspan="3" valign="top">
+      Mouth closed except during food ingestion; no undulating membrane
+    </td>
+    <td valign="top">
+      1
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td colspan="3" valign="top">
+      Mouth always open; with undulating membrane
+    </td>
+    <td valign="top">
+      2
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      1.
+    </td>
+    <td colspan="5" valign="top">
+      <i>Gymnostomina</i>.
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      a.
+    </td>
+    <td width="45%" valign="top">
+      Mouth terminal or subterminal. Food is swallowed and not
+      introduced by currents
+    </td>
+    <td valign="top">
+      Family <a href="#Enchelinidae1"><i>Enchelinidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      b.
+    </td>
+    <td width="45%" valign="top">
+      Mouth terminal or subterminal; body frequently drawn out into
+      long process; mouth may have specialized framework
+    </td>
+    <td valign="top">
+      Family <a href="#Trachelinidae"><i>Trachelinidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      c.
+    </td>
+    <td width="45%" valign="top">
+      Mouth central or posterior; pharynx with supporting
+      framework
+    </td>
+    <td valign="top">
+      Family <a href="#Chlamydodontidae1"><i>Chlamydodontidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      2.
+    </td>
+    <td colspan="5" valign="top">
+      <i>Trichostomina</i>.
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      a.
+    </td>
+    <td width="45%" valign="top">
+      Mouth anterior or central; pharynx short or absent;
+      peristomial depression faint or absent
+    </td>
+    <td valign="top">
+      Family <a href="#Chiliferidae1"><i>Chiliferidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      b.
+    </td>
+    <td width="45%" valign="top">
+      Mouth central; pharynx long, tubular; cilia in two broad zones
+    </td>
+    <td valign="top">
+      Family <i>Urocentridæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      c.
+    </td>
+    <td width="45%" valign="top">
+      Mouth posterior; form asymmetrical; cilia dispersed
+      or limited to oral region
+    </td>
+    <td valign="top">
+      Family <i>Microthoracidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      d.
+    </td>
+    <td width="45%" valign="top">
+      Mouth anterior or central. Peristomial depression
+      clearly marked.
+    </td>
+    <td valign="top">
+      <i>Paramœcidæ</i><br>
+      (One genus, <i>Paramœcium</i>)
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      e.
+    </td>
+    <td width="45%" valign="top">
+      Mouth at end of long peristome running along ventral side;
+      body dorso-ventrally or laterally compressed; left edge
+      of peristome with great, sail-like undulating membrane
+    </td>
+    <td valign="top">
+      Family <a href="#Pleuronemidae1"><i>Pleuronemidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      f.
+    </td>
+    <td width="45%" valign="top">
+      Mouth and pharynx distinct, posterior; cilia uniform.
+      Parasites in ruminants.
+    </td>
+    <td valign="top">
+      Family <i>Isotrichidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top" align="left">
+      g.
+    </td>
+    <td width="45%" valign="top">
+      Mouth absent; body vermiform, cilia uniform. Usually
+      parasites.
+    </td>
+    <td valign="top">
+      Family <a href="#Opalinidae1"><i>Opalinidæ</i></a>
+    </td>
+  </tr>
+</table>
+<br><a name="Enchelinidae"></a><a name="Enchelinidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="4" align="center">
+      <b><i>Key to marine genera of Enchelinidæ</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="left">
+      <i>Diagnostic characters:</i> Form ellipsoid or ovoid; the
+      mouth is invariably terminal and is usually
+      round&mdash;more rarely slit-formed; it is closed except
+      when food is taken. An Å“sophagus when present is a
+	  short, invariably non-ciliated tube which is usually
+	  surrounded by a more or less clearly defined buccal
+	  armature. The anus is usually terminal. Large food
+	  particles are swallowed, never introduced by currents.
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      1.
+    </td>
+    <td valign="top" colspan="2">
+      Body naked
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td valign="top" align="right">
+      2.
+    </td>
+    <td valign="top" colspan="2">
+      Body inclosed in a shell or coat
+    </td>
+    <td valign="top">
+      7
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      3.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Cilia uniform about the entire body; body symmetrical
+    </td>
+    <td valign="top">
+      4
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Cilia in the mouth region longer than the others; body
+      symmetrical
+    </td>
+    <td valign="top">
+      5
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Bristles, or tentacles, in addition to cilia
+    </td>
+    <td valign="top">
+      6
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      4.
+    </td>
+    <td colspan="2" valign="top">
+      Mouth terminal; body ellipsoidal to ovoid
+    </td>
+    <td valign="top">
+      Genus <i>Holophrya</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      5.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Mouth terminal; body elongate, flexible, and elastic
+    </td>
+    <td valign="top">
+      Genus <i>Chænia</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Mouth terminal; "neck" highly elastic; entire body
+      flexible; conical "head"
+    </td>
+    <td valign="top">
+      Genus *<a href="#Lacrymaria"><i>Lacrymaria</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Mouth terminal; "neck" highly elastic; entire body
+      flexible; "head" square
+    </td>
+    <td valign="top">
+      Genus *<a href="#Trachelocerca"><i>Trachelocerca</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      d.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Mouth terminal; "neck" highly elastic; no separate
+      mouth-bearing portion
+    </td>
+    <td valign="top">
+      Genus <i>Lagynus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      6.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Body asymmetrical; bristles in addition to cilia
+    </td>
+    <td valign="top">
+      Genus <i>Stephanopogon</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="50%" valign="top" align="left">
+      Body symmetrical; 4 small tentacles from mouth; cilia
+      and cirri in girdles
+    </td>
+    <td valign="top">
+      Genus *<a href="#Mesodinium"><i>Mesodinium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      7.
+    </td>
+    <td colspan="2" valign="top">
+      Shell composed of small sculptured pieces; cilia long,
+      uniform
+    </td>
+    <td valign="top">
+      Genus *<a href="#Tiarina"><i>Tiarina</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+</table>
+</center>
+
+
+<br>
+<br><a name="Lacrymaria"></a>
+<br>
+<h3>Genus LACRYMARIA Ehr. '30.</h3>
+
+<div class="center"><span class="syn">(Ehrenberg, C. G., 1838;
+Perty '52; Clapar&egrave;de &amp; Lachmann '58;<br>
+Stein 59-83; Quennerstedt '66, '67; Fromentel '74; Kent '81;
+Gruber '84;<br>
+Gourret &amp; Roeser '86; B&uuml;tschli '88;
+Schewiakoff '89.)</span></div>
+
+<p>Body short to very long flask-shape; for the most part contractile,
+especially in the neck region. The posterior end is rounded or
+pointed. The main character is the mouth-bearing apex, which "sets
+like a cork in the neck of the flask." One or more circles of long
+cilia at the base of the mouth portion or upon it. The body is
+spirally striped. Contractile vacuole terminal, with sometimes one or
+two further forward. Macronucleus central, globular to elongate,
+sometimes double. Food mainly bacteria. Fresh and salt water.</p>
+
+
+<a name="Lacrymaria_lagenula"></a>
+<br>
+<p class="noindent"><b>Lacrymaria lagenula</b> Clap. &amp; Lach.
+Fig. 28, a, b.</p>
+
+<p class="syn">Synonym: <i>L. tenuicula</i> Fromentel '74.</p>
+
+<p>Body more or less flask-shape, two or three times as long as broad,
+with conical apex, which is slightly elastic and protrusible; surface
+obliquely striate, with well-defined lines, 14 to 16 in number; cilia
+uniform on the body, with a crown of longer ones at the base of the
+conical proboscis. The body cilia are not thickly placed except
+around the proboscis. The endoplasm is thickly packed with large
+granules (food particles) in the anterior half and with finely
+granular particles in the posterior half. The elongate macronucleus
+lies a little above the center among the larger granules; the
+contractile vacuole is double, one on each side of the median line
+and at the posterior end of the body among the finer granules. The
+anus is posterior. Length 90&micro; to 160&micro;; greatest width assumed 65&micro;.
+When fully expanded the posterior end assumes a curious polyhedral
+form. (Fig. 28 b.)</p>
+
+<p>This form differs slightly from others of the same species as
+described by different observers, the most striking difference being
+the presence of two contractile vacuoles in place of the usual one.
+These are very slow to fill and grow to a large size before diastole.
+The membrane is very tough and retains its form easily under pressure
+of the cover glass. Another characteristic feature is the flattening
+of the surfaces between the striæ. Decaying algæ.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_28.jpg">
+<img src="images/fig_28t.jpg" width="300" border=0
+alt="Lacrymaria lagenula"></a>
+</td><td align="center">
+<b>Fig. 28.&mdash;<br>
+<i>Lacrymaria lagenula</i>.</b>
+<br>
+<br>
+<a href="images/fig_28.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Lacrymaria_coronata"></a>
+<br>
+<p class="noindent"><b>Lacrymaria coronata</b> Cl. &amp; Lach. '58.  Fig. 29.</p>
+
+
+<table class="imagetable" align="right" ><tr><td>
+<center>
+<a href="images/fig_29.jpg">
+<img src="images/fig_29t.jpg" width="200" border=0
+alt="Lacrymaria coronata"></a>
+<br>
+<b>Fig. 29.&mdash;<br>
+<i>Lacrymaria coronata</i>.</b>
+<br>
+<br>
+<a href="images/fig_29.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p class="syn">Synonyms: <i>L. lagenula</i> Cohn '66; Möbius '88;
+<i>L. cohnii</i> ? Kent '81; <i>L. versatilis</i> Quen. '67.</p>
+
+<p>Form flask-like and similar to <i>L. lagenula</i>, contractile but tough.
+The contractile vacuole is terminal, the proboscis is short, slightly
+raised and separated from the body by a deep cleft; the buccal cilia
+are inserted part way up on the proboscis. Form changeable, from
+short, sac-like to elongate and vermiform. Length 85&micro;.</p>
+
+<p>This species is not very different from <i>L. lagenula</i>,
+but I noted that
+in addition to the elongate nucleus, the body striæ are much more
+apparent here and seem to sink into the cuticle, giving the
+periphery, especially at the collar region, a curious crenulated
+effect. The endoplasm is very densely granular and colored a
+blue-green, probably from food particles. The number of striæ is much
+larger than in the preceding species. The membrane is very tough and
+retains the shape of the body, even with the full pressure of the
+cover glass. Micronucleus and trichocysts were not observed.</p>
+
+
+<br>
+<br><a name="Trachelocerca"></a>
+<br>
+<h3>Genus TRACHELOCERCA (Ehr. '83) Cohn '66.</h3>
+
+<div class="center"><span class="syn">(Quennerstedt '67;
+Gruber '87; Entz '84; Kent '81; Gourret &amp; Roeser '88;<br>
+B&uuml;tschli '88; Schewiakoff '89; Shevyakov '96.)</span></div>
+
+<p>The only well-known representative is very elongate, large (up to 3
+mm. Van Beneden), and very contractile. The main feature of
+importance in distinguishing it is the 4-part structure of the mouth
+region, which, however, may not be obvious. Pharynx faint and smooth.
+Contractile vacuole terminal. Macronucleus in one central body or in
+numerous pieces scattered throughout the cell.  Salt water.</p>
+
+
+<a name="Trachelocerca_phoenicopterus"></a>
+<br>
+<p class="noindent"><b>Trachelocerca phœnicopterus</b>
+Cohn '66.  Fig. 30.</p>
+
+<p class="syn">Synonyms: <i>T. sagitta</i> Ehr. '40, Stein '59;
+<i>T. tenuicollis</i> Quennerstedt '67, Kent '81;
+<i>T. minor</i> Gruber '87, Shevyakov '96.</p>
+
+<p>The body is extremely elongate and ribbon-like, and this, combined
+with its wonderful power of extension and retraction, makes it one of
+the most curious and interesting of microscopic forms. The anterior
+end is square or cylindrical; the type species has a four-sided
+mouth, but many specimens may be found which have a plain cylindrical
+mouth region. One reason for this may be the fact that the extremity
+gets broken off. In one instance I noticed a very large form with the
+anterior end under some debris, which evidently held it tight, for
+the body of the ciliate was thrashing back and forth and twisting
+itself into knots, etc., like a nematode worm. Finally, the anterior
+end broke off with about one-tenth of the body; the remainder, in an
+hour, had regenerated a new anterior end with long cilia, but with no
+indication of four sides. The small anterior piece was also very
+lively, moving about and eating like the normal animal; its history,
+however; was not followed. This species appears to be variable in
+other ways as well; thus, in some cases the posterior end is rounded
+(cf. Entz '84); in others it is pointed (cf. Kent '81, Cohn '66, et
+al.).</p>
+
+<p>Again, the macronucleus may be a single round body (Entz '84,
+B&uuml;tschli '88) or in two parts (Kent '81), or in many parts scattered
+about the body (Gruber). In the Woods Hole forms the tail is
+distinctly pointed and turned back sharply, forming an angle at the
+extremity. The cilia on this angular part are distinctly longer than
+the rest. The function of this posterior part is apparently to anchor
+the animal while it darts here and there upon the tail as a pivot,
+contracting and expanding the while. The body is finely striated with
+longitudinal markings; when contracted there are no transverse
+markings nor annulations. The nucleus is in the form of many
+fragments scattered throughout. Length of large specimen 1.7 mm.</p>
+
+
+<center>
+<table class="imagetable"><tr><td align="center">
+<a href="images/fig_30.jpg">
+<img src="images/fig_30t.jpg" width="550" border=0
+alt="Trachelocerca phoenicopterus"></a>
+<br>
+<b>Fig. 30.&mdash;<i>Trachelocerca phœnicopterus</i>.</b>
+&nbsp; &nbsp;
+<a href="images/fig_30.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Mesodinium"></a>
+<br>
+<h3>Genus MESODINIUM Stein '62.</h3>
+
+<div class="center"><span class="syn">(Maupas '82, '84;
+Entz '84; Shevyakov '96.)</span></div>
+
+<p>The main part of the body is globular or conical, with a short,
+platform-like oral region, and a deep annular groove about the middle
+of the body. The Å“sophagus is rather long, and smooth or
+longitudinally striped. One or more rings of cirri rise in the
+groove. If more than one ring of cirri are present, the anterior set
+usually point forward and lie close to the anterior part of the body.
+The posterior set, on the other hand, cling close to the posterior
+region of the body and give to it a peculiar encapsuled appearance.
+The most characteristic feature is the presence of four short
+tentacle-like processes which can be protracted and retracted from
+the oral region. (Mereschowsky says that the entire anterior half is
+more or less contractile.) The macronucleus is horseshoe-shaped or
+ovoid and is situated in the posterior half of the body. The
+contractile vacuole is also posterior.</p>
+
+<p>Movement consists in rapid swimming, with rotation on its axis, or in
+creeping by means of its anterior cirri, or in sudden jumping, by
+which it apparently clears a distance of 20 times its diameter in one
+bound. Mouth parts may also be used for attachment to foreign bodies.
+The moving periods alternate with quiescent periods, during which the
+organisms with their outstretched and radiating cirri resemble the
+heliozoön <i>Actinophrys</i>.</p>
+
+
+<a name="Mesodinium_cinctum"></a>
+<br>
+<p class="noindent"><b>Mesodinium cinctum</b>, n. sp.  Fig. 31.</p>
+
+<p>Body spherical to pyriform, constricted near the middle, the
+constriction dividing the body into dissimilar parts. The anterior
+part is broadly pyriform, somewhat plastic and hyaline, with an oral
+extremity which is sometimes hollow, sometimes evaginated and convex.
+Upon this flexible anterior part there are four short but distensible
+tentacles. The posterior part is granular and usually filled with
+food particles; it is well rounded and holds the nucleus and
+contractile vacuole. The entire body is surrounded by a fine cuticle.
+The nucleus is elongate and extends through the greater part of the
+posterior half. The contractile vacuole lies on one side, near the
+girdle. The mouth is on the anterior pole in the tentacle region. The
+motile organs are cirri and cilia, all inserted in the constriction.
+There are two sets of cirri and one of cilia; the latter stand out
+radially from the girdle and are usually in motion. The cirri of one
+set, the anterior, extend forward about twice the length of the
+anterior half; those of the posterior set closely engirdle the lower
+half, reaching not quite to the posterior extremity. These are
+somewhat hyaline and are closely approximated, giving the impression
+of a tight-fitting crenulate casing about the lower half. The cirri
+are sharply pointed, much broader at the base, and the two sets are
+so placed that, looked at from above, they have the appearance of a
+twisted cord. (Fig. 31 b.) Movement erratic; sometimes the animal
+swims steadily forward with mouth in front; again it shoots across
+the field of the microscope, either backward or forward or sideways,
+through the action of its powerful cirri. It is often quiet, usually
+mouth downward, and is held in place by adhesion of the tentacles. In
+this position it looks strikingly like a heliozoön.</p>
+
+<p>Length 35&micro;; greatest width 30&micro;. Not uncommon.</p>
+
+<p>The chief features by which this species is distinguished from the
+frequently described <i>M. pulex</i> of Europe are the number of anterior
+cirri and the ring of true cilia in place of the central girdle of
+cirri. The European form is described with four anterior bristles;
+the present form has from 28 to 32. The radial cilia differ decidedly
+from the more powerful cirri and they are not in one plane, so that
+counting is difficult; they are not closely set. The presence of
+tentacles makes these forms of especial theoretical interest,
+especially in the light of the origin of <i>Suctoria</i>.</p>
+
+
+<center>
+<table class="imagetable"><tr><td align="center">
+<a href="images/fig_31.jpg">
+<img src="images/fig_31t.jpg" width="400" border=0
+alt="Side and top views of Mesodinium cinctum"></a>
+<br>
+<b>Fig. 31.&mdash;Side and top views of <i>Mesodinium cinctum</i>.</b>
+<br>
+<br>
+<a href="images/fig_31.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Tiarina"></a>
+<br>
+<h3>Genus TIARINA R. S. Bergh '79.</h3>
+
+<div class="center"><span class="syn">(Clapar&egrave;de &amp;
+Lachmann '58.)</span></div>
+
+<p>Body subcylindrical, pointed posteriorly, two and one-half times as
+long as broad; encased in covering composed of separate pieces
+arranged in five girdles. The pieces bear processes which rest
+against neighboring pieces of the girdle. Mouth large, anus terminal
+near contractile vacuole. The macronucleus is simple and round. Salt
+water.</p>
+
+
+<a name="Tiarina_fusus"></a>
+<br>
+<p class="noindent"><b>Tiarina fusus</b> (Cl. &amp; Lach.)
+emend R. S. Bergh.</p>
+
+<p class="syn">Synonyms: <i>Coleps fusus</i> Cl. &amp; Lach. '58;
+Daday '86; Möbius '88,
+Lauterborn '94; Shevyakov '86.</p>
+
+<p>This form, which resembles <i>Coleps</i> rather closely, was placed as a
+separate genus by R. S. Bergh. The skeletal parts consist of five
+zones of needles composed of an organized substance and embedded in
+the cortical plasm, the last zone coming to a point at the posterior
+end. The needles have lateral processes, which give a latticed
+appearance to the casing. The cilia are long, with a specialized
+crown of still longer ones at the oral end; they arise outside of the
+skeletal elements and do not pass between them, as in <i>Coleps</i>.</p>
+
+
+<br><a name="Trachelinidae"></a><a name="Trachylinidae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="4" align="center">
+      <b><i>Key to marine genera of Trachelinidae.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="left">
+      <i>Diagnostic characters:</i> Body bilateral, or asymmetrical
+         by local prolongations; usually compressed or flattened
+         laterally, the left side more convex than the right. The
+         essential feature is the position and character of the
+         mouth. This is either a long slit extending from the
+         anterior end well down the ventral surface, or the
+         posterior part only of a ventral furrow remains open as
+         a round or elongate mouth some distance from the anterior
+         end. The entire mouth region of the body is usually drawn
+         out into an elongate tapering proboscis which is generally
+         curved dorsally at the extremity. An Å“sophagus is
+         short or absent altogether; when present it is supported
+         by a stiff buccal armature. Cilia are uniform about entire
+         body or limited to the flat right side. Food is swallowed.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      1.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top" align="left">
+      Proboscis easily distinguished from the main body
+    </td>
+    <td valign="top">
+      2
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top" align="left">
+      Proboscis not marked off from main body; body flat;
+      both surfaces striated
+    </td>
+    <td valign="top">
+      Genus *<a href="#Loxophyllum"><i>Loxophyllum</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      2.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top" align="left">
+      Mouth runs the entire length of proboscis; entire body
+      uniformly ciliated
+    </td>
+    <td valign="top">
+      Genus <i>Amphileptus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top" align="left">
+      Mouth runs the entire length of proboscis; body flat;
+      right side only is ciliated
+    </td>
+    <td valign="top">
+      Genus *<a href="#Lionotus"><i>Lionotus</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="55%" valign="top" align="left">
+      Proboscis much drawn out, flexible; mouth at its base
+    </td>
+    <td valign="top">
+      Genus <i>Dileptus</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+</table>
+
+
+<br>
+<br><a name="Loxophyllum"></a><a name="Loxophyllum1"></a>
+<br>
+<h3>Genus LOXOPHYLLUM Dujardin '41.</h3>
+
+<div class="center"><span class="syn">(Duj. '41; Wrzesniowski '69;
+Quennerstedt '65; '67; Cohn '66;<br>
+Entz '84; Gourret &amp; Roeser '88;
+B&uuml;tschli '88; Shevyakov '96.)</span></div>
+
+<p>The body is flat and somewhat leaf-shape, flexible, and elastic. The
+anterior end is somewhat proboscis-like and flexible, but is not
+sharply demarcated as in <a href="#Lionotus1"><i>Lionotus</i></a>.
+The central portion of the body
+is developed into a more or less arched dorsal mass, which usually
+contains the nuclei and contractile vacuoles. As a result of this
+local thickening, the body is surrounded by a thin hyaline margin.
+This, however, may be absent on the right side in some species. The
+mouth reaches from the anterior extremity to a short distance from
+the end, and usually approaches the left edge. An anus is present
+near the posterior end of the dorsal swelling. Trichocysts are
+numerous on the ventral surface, and often on the dorsal surface,
+where they are inclosed in minute papilla-like swellings.
+Cilia-distribution controverted. Maupas and B&uuml;tschli hold that
+ventral surface alone is ciliated; others (Kent and Dujardin) that
+cilia are uniformly distributed. The entire body, dorsal and ventral
+surfaces alike, are uniformly striated. The contractile vacuole lies
+posteriorly, on the right side and in the dorsal swelling. In the
+fresh-water form <i>L. meleagris</i>, it is connected with a long canal
+whose swellings are frequently taken for additional contractile
+vesicles (B&uuml;tschli); in the marine form described below the canal is
+not developed and a series of vacuoles takes its place; these are all
+contractile. The macronucleus may be single, double, quadruple,
+band-formed, or rosette-formed. Movement is steadily progressive and
+peculiarly gliding. Fresh and salt water.</p>
+
+
+<a name="Loxophyllum_setigerum"></a>
+<br>
+<p class="noindent"><b>Loxophyllum setigerum</b> Quenn. '67.</p>
+
+<p class="syn">Synonyms: <i>Litosolenus armatus</i> Stokes '93;
+<i>Litosolenus verrucosa</i>
+Stokes '93.</p>
+
+<p>The body is flattened, irregular in outline, obtusely pointed
+anteriorly, the point being turned to the right; rounded posteriorly.
+The left edge is nearly straight, the right considerably arched with
+a few setæ on the posterior half. Contractile vacuoles are numerous,
+dorsal in position and on the right side. The macronueleus is beaded,
+the several spheres connected.</p>
+
+
+<br>
+<p class="noindent">Variety <b>armatum</b> (Cl. &amp; Lach.) Fig. 32.</p>
+
+<p>Under the name <i>Litosolenus armatus</i>, Stokes described a form from
+brackish water near New York, which should unquestionably be referred
+to the genus <a href="#Loxophyllum1"><i>Loxophyllum</i></a>,
+and I believe to Quennerstedt's species
+<i>setigerum</i>. While the latter possesses only a few setæ, the former
+has a number of them, and Stokes described his species as having a
+variable number. For this reason I include the Woods Hole form under
+the tentative name <i>armatum</i>, as a variety of Quennerstedt's <i>L.
+setigerum</i>. The flat margins are distinctly striated longitudinally,
+and faintly marked radially, on the dorsal surface. Longitudinal
+elevated striæ also run the length of the dorsal hump and upon the
+entire ventral surface. The ventral surface is alone ciliated. Upon
+the edges of the flat border are sharp-pointed, colorless, spine-like
+processes, situated at equal distances around the entire periphery
+except at the anterior end. Each spine is thick at the base and
+tapers to a full point which is curved upward&mdash;<i>i. e.</i>, dorsally
+(fig. 32, a, b). The entire body is plastic and contractile, turning
+its leaf-like edge readily over objects upon which it creeps. The
+cilia are fine and uniform, with a tendency to lengthen in the oral
+region.</p>
+
+<p>Length 100&micro;; greatest width assumed on contraction 85&micro;; when normal
+about 50&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_32.jpg">
+<img src="images/fig_32t.jpg" width="400" border=0
+alt="Loxophyllum setigerum, var. armatum.
+a, b, c, ventral, dorsal, and lateral aspects."></a>
+<br>
+<b>Fig. 32.&mdash;<i>Loxophyllum setigerum</i>, var. <i>armatum</i>.<br>
+a, b, c, ventral, dorsal, and lateral aspects.</b>
+<br>
+<br>
+<a href="images/fig_32.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Lionotus"></a><a name="Lionotus1"></a>
+<br>
+<h3>Genus LIONOTUS Wrzesniowski '70.</h3>
+
+<div class="center"><span class="syn">(Incorrectly called
+<i>Litonotus</i> by many. Entz '84; Gruber '84;<br>
+B&uuml;tschli '88; Kent '81; Schewiakoff '89; Shevyakov '96.)</span></div>
+
+<p>The body is elongate and somewhat lance-shaped, widest at the central
+part and tapering to a point at the anterior end. The posterior end
+may be similarly tapered or rounded. The anterior end frequently
+proboscis-like, flat, and flexible, while the entire body is more or
+less elastic and contractile.  The right side is flattened and alone
+provided with cilia, while the left side of the body proper is
+arched; on the left side of the proboscis is a row of coarse cilia
+resembling an adoral zone, and a row of trichocysts. A long peristome
+stretches down the thin, ventral side of the proboscis, and the mouth
+proper is situated at the junction of the proboscis and body; the
+mouth, as a rule, is invisible. The ciliated right side alone is
+striated in the majority of species. The contractile vacuole may be
+single or multiple, usually in the posterior region of the body and
+dorsal in position. The macronucleus is usually double, rarely single
+or quadruple, but may occasionally break into numerous smaller
+pieces.  Movement, free-swimming or gliding, with especial tendency
+to get under clumps of foreign matter.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Lionotus_fasciola"></a>
+<br>
+<p class="noindent"><b>Lionotus fasciola</b> Ehr.  Fig. 33.</p>
+
+<p class="syn">Synonyms. <i>Amphileptus fasciola</i> Ehr. '38;
+Dujardin '41; Lachmann '56;  Cohn '66, Diesing '65.<br>
+<i>Loxophyllum fasciola</i> Clapar&egrave;de &amp; Lachmann '58;
+Balbiani '61.<br>
+<i>Loxophyllum duplostriatum</i> Maupas '83. Shevyakov '96.</p>
+
+<p>Body frequently brown or brilliant yellow in color, somewhat sigmoid
+in form with tapering anterior end, the extremity of which is turned
+dorsally. The proboscis is about half the entire length and is not
+sharply marked from the rest of the body but tapers gradually, its
+base being equal to the diameter of the body at its middle point. The
+body is slightly contractile and the posterior end is carried to a
+rounded point, but not into a distinct tail. Unlike the fresh-water
+variety, this one has no hyaline margin nor hyaline caudal region,
+and the contractile vacuole is double or multiple on the dorsal side
+near the posterior end. Cilia are present only on the under (right)
+side, with, however, a row of large cilia marking the course of the
+elongate mouth, upon its left side. The right side is striated, the
+left arched and without markings. The endoplasm is finely granular
+with, however, larger food particles in the process of digestion,
+while specimens are occasionally seen with the natural form
+completely lost through distortion caused by over-large captures (Cf.
+also Wrzesniowski '70, p. XXIII, fig. 32). Movement continuous, slow,
+and gliding; very little tendency to jerking movements. Macronucleus
+double, both parts spherical, and placed in about the center of the
+larger part of the body; closely approximated but not, as Schewiakoff
+described, connected. In conjugation, a large form unites with a
+smaller one, the mouth parts being connected. Details of conjugation
+and macronuclei not made out. Length 200&micro; to 600&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_33.jpg">
+<img src="images/fig_33t.jpg" width="500" border=0
+alt="Lionotus fasciola"></a>
+<br>
+<b>Fig. 33.&mdash;<i>Lionotus fasciola</i>.</b>
+&nbsp; &nbsp;
+<a href="images/fig_33.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<center>
+<br><a name="Chlamydodontidae"></a><a name="Chlamydodontidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="4" align="center">
+      <b><i>Key to marine genera of Chlamydodontidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="left">
+      <i>Diagnostic characters:</i> Form usually ellipsoid, never
+      very elongate. Transverse section of body circular or
+      elliptical. The mouth is usually some distance from the
+      anterior end and may be in the posterior part. Sometimes it
+      is in the center of the ventral surface, again on the right
+      side. The Å“sophagus invariably has a well-developed
+      buccal armature, or a smooth peculiarly built
+      Å“sophageal tube. Food particles of large size.
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      1.
+    </td>
+    <td colspan="2" valign="top">
+      Body cylindrical. Cilia about entire body
+    </td>
+    <td valign="top">
+      Genus *<a href="#Nassula"><i>Nassula</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      &nbsp;
+    </td>
+    <td colspan="2" valign="top">
+      Body flat
+    </td>
+    <td valign="top">
+      2
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      2.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top">
+      Without a caudal process
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top">
+      With a caudal process
+    </td>
+    <td valign="top">
+      5
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      3.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top">
+      Anterior end angular
+    </td>
+    <td valign="top">
+      4
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top">
+      Anterior end rounded
+    </td>
+    <td valign="top">
+      Genus <i>Chlamydodon</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      4.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top">
+      Dorsal striæ and cilia present, ventral cilia longer
+    </td>
+    <td valign="top">
+      Genus <i>Orthodon</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top">
+      Dorsal striæ and cilia absent; posterior end not
+      pointed
+    </td>
+    <td valign="top">
+      Genus *<a href="#Chilodon"><i>Chilodon</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="55%" valign="top">
+      Dorsal striæ and cilia absent; posterior end pointed
+    </td>
+    <td valign="top">
+      Genus <i>Scaphidiodon</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      5.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top">
+      Caudal spine with posterior bristle-like cilia
+    </td>
+    <td valign="top">
+      6
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top">
+      Caudal spine without posterior bristle-like cilia;
+      ventral cilia reduced
+    </td>
+    <td valign="top">
+      Genus <i>Trochilia</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      6.
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top">
+      With pigment spot on anterior angle
+    </td>
+    <td valign="top">
+      Genus <i>&AElig;gyria</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top">
+      Without such pigment spot
+    </td>
+    <td valign="top">
+      Genus <i>Onychodactylus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="55%" valign="top">
+      Cilia on right edge only of greatly reduced ventral surface
+    </td>
+    <td valign="top">
+      Genus *<a href="#Dysteria"><i>Dysteria</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Nassula"></a>
+<br>
+<h3>Genus NASSULA Ehr. '33</h3>
+
+<div class="center"><span class="syn">(Dujardin '41; Stein '67;
+Cienkowsky '55; Cohn '66; Clap. et Lach. '58;<br>
+Kent '81; Maupas '83; Entz '84; Fabre-Domergue '88; B&uuml;tschli
+'88; Shevyakov '96.)</span></div>
+
+<p>The body is ovoid or cylindrical, with well-rounded ends, and in some
+cases slightly flattened. The mouth is ventral and placed some
+distance from anterior end (1/4 to 1/3 total length). A slight
+depression on the ventral surface marks the mouth region, which is
+further indicated by larger and more powerful cilia. The rest of the
+body is uniformly ciliated. The entire body is marked by clearly
+defined spiral stripes. The mouth is circular and the Å“sophagus is
+supported by a considerable armature, which usually extends dorsally
+and to the left, rarely to the right. In some cases the structure of
+this armature is indistinct; again it can be clearly seen to consist
+of definite rods (St&auml;bchen). The anus is probably always terminal.
+Contractile vacuoles are variable in different species. In some cases
+there is but one, which is placed at the posterior end or centrally
+on the ventral side; in others there may be four&mdash;two dorsal and two
+ventral. In many cases trichocysts are uniformly distributed.
+Sometimes the body is colorless; again, and more often, it is
+brightly colored with red, blue, brown, or black pigment. The
+macronucleus is globular and central, occasionally band-form and with
+numerous attached micronuclei. Food substance varied, usually
+vegetable matter, see, however, below. Cysts are globular. Movement
+is a steady progression, combined with rolling.</p>
+
+
+<a name="Nassula_microstoma"></a>
+<br>
+<p class="noindent"><b>Nassula microstoma</b> Cohn '66.  Fig. 34.</p>
+
+<p class="syn">Synonyms: <i>Paramœcium microstomum</i> Cl. et Lach. '58, Gourret et
+Roeser '88; <i>Isotricha microstomum</i> Kent '81.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_34.jpg">
+<img src="images/fig_34t.jpg" width="300" border=0
+alt="Nassula microstoma"></a>
+<br>
+<b>Fig. 34.&mdash;<i>Nassula microstoma</i>.</b>
+<br>
+<br>
+<a href="images/fig_34.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>Body subcylindrical, rounded at each extremity, not quite twice as
+long as broad. A slight depression on one surface marks the position
+of the mouth, this depression being indicated by a row of longer
+cilia. The mouth is extremely small and is surrounded by a curious
+buccal armature. This is not made up of bars or rods, as in most
+species of <i>Nassula</i>, but appears perfectly smooth and uniform except
+for the considerable swelling at the inner end. The cuticle is firm
+and unyielding and marked by longitudinal and somewhat spiral rows of
+cilia and trichocysts. Under the microscope this is one of the most
+pleasing forms found at Woods Hole. Its color is yellowish brown from
+the presence of brilliant particles of coloring matter held in the
+cortical plasm, and, as it slowly rolls along, these particles and
+the black trichocysts give to the organism a peculiar sparkling
+effect. The macronucleus is almost central; the contractile vacuole
+posterior. The endoplasm appears well filled with food bodies, some
+of which could be distinguished as
+<a href="#Amphidinium2"><i>Amphidinium</i></a> and
+<a href="#Glenodinium2"><i>Glenodinium</i></a>.</p>
+
+<p>Length 55&micro;; greatest diameter 30&micro;.</p>
+
+
+<br>
+<br><a name="Chilodon"></a>
+<br>
+<h3>Genus CHILODON Ehr.</h3>
+
+<div class="center"><span class="syn">(Dujardin '41; Engelmann '78;
+Stein '54, '58; Kent '81; B&uuml;tschli '88;<br>
+Gruber '83; Cienkowsky '55; Möbius '88;<br>
+Clap. et Lach '58; Wrzesniowksi '65; Shevyakov '96.)</span></div>
+
+<p>Small forms, greatly flattened dorso-ventrally and almost egg-form in
+outline. The anterior end is bent distinctly to the left and forms a
+characteristic process, which, together with the entire margin of the
+body, is soft and flexible. The posterior end is, as a rule, broadly
+rounded. The ventral surface is finely striate, and this surface
+alone is ciliated. The lines of cilia converge at the mouth, and at
+this region the cilia are somewhat larger and more distinct, thus
+forming a functional adoral zone. The mouth is median and is situated
+in the anterior half of the body. It is surrounded by a well-defined
+armature, composed usually of from 10 to 16 rods. The contractile
+vacuoles are quite varied and from one to many in number, the number
+increasing with the size of the individual. The macronucleus is
+usually single, elliptical in form, and centrally placed; one
+micronucleus. Reddish granular pigment and trichocysts are
+occasionally present.</p>
+
+
+<a name="Chilodon_cucullulus"></a>
+<br>
+<p class="noindent"><b>Chilodon cucullulus</b> M&uuml;ll., sp.  Fig. 35.</p>
+
+<p class="syn">Synonyms; <i>Colpoda cucullus</i> O. F. M&uuml;ller;
+<i>Loxodes cucullulus</i>; <i>Chilodon uncinatus</i> Ehr. '58,
+Perty '52, Dujardin '41; <i>L. dentatus</i> Duj., etc.</p>
+
+<p>This extremely variable form has received so many different names
+that it hardly pays to enumerate them. It is one of the commonest and
+most widely spread ciliates known, although at Woods Hole I was
+surprised to see it so rarely. It is the type species of the genus
+and needs no further description. The specimens observed at Woods
+Hole had numerous contractile vacuoles and were 42 to 45&micro; long and
+from 28 to 32&micro; wide.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_35.jpg">
+<img src="images/fig_35t.jpg" width="350" border=0
+alt="Chilodon cucullulus"></a>
+</td><td align="center">
+<b>Fig. 35.&mdash;<br>
+<i>Chilodon cucullulus</i>.</b>
+<br>
+<br>
+<a href="images/fig_35.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Dysteria"></a>
+<br>
+<h3>Genus DYSTERIA Huxley '57.</h3>
+
+<div class="center"><span class="syn">(Cl. et Lach. '58;
+Entz '84; Möbius '88; Shevyakov '96.)</span></div>
+
+<p>Small forms, firm in outline, and colorless or slightly colored. The
+body is somewhat clam-shaped, flattened, slightly curved or straight
+on the right side, the other more convex. The true ventral side is
+only a narrow strip along the right and anterior edge of the body,
+the apparent ventral side being a fold of the very large dorsal
+surface which comes around ventrally, forming a valved structure
+somewhat analogous to a clam shell. Cilia are limited to the outer
+edge of the small ventral surface, which also bears a peculiar spine
+at the posterior end. Behind this spine are larger cilia. The mouth
+opening lies in the anterior widened portion of the ventral surface
+and is connected with a smooth tubular pharynx. The right half of the
+dorsal side, <i>i.e.</i>, the apparent dorsal side, is arched and bears
+longitudinal ridges. Two to four contractile vacuoles are placed on
+the ventral side. The macronucleus is usually dorsal, elliptical, and
+cleft, with one micronucleus attached. Fresh and salt water.</p>
+
+
+<a name="Dysteria_lanceolata"></a>
+<br>
+<p class="noindent"><b>Dysteria lanceolata</b> Cl. et Lach.  Fig. 36.</p>
+
+<p class="syn">Synonym: <i>Cypridium lanceolatum</i> Kent '81.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_36.jpg">
+<img src="images/fig_36t.jpg" width="125" border=0
+alt="Dysteria lanceolata"></a>
+<br>
+<b>Fig. 36.&mdash;<br>
+<i>Dysteria lanceolata</i>.</b>
+<br>
+<br>
+<a href="images/fig_36.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>Outline of the flattened body ovoid; body consists of two valve-like
+portions; the edge of the right valve is nearly straight, that of the
+left valve more or less sinuous; anteriorly it is cut away, obliquely
+and posteriorly it has a deep indentation in which the seizing spine
+rests. The cilia are confined to the ventral surface, here reaching,
+however, from the anterior dorsal extremity to below the posterior
+indentation. Posteriorly the cilia become larger, corresponding to
+the larger cirri of <i>D. armata</i>, which are posterior to the spine.
+The mouth lies between the two valves and is surrounded by a long and
+smooth buccal armature which passes downward and backward to the left
+a distance equal to about half the entire body length. The
+macronucleus is situated in the dorsal region in the central part of
+the body. There are two contractile vacuoles, one behind the center
+of the buccal armature, the other near the inner end of this organ.
+Movement is in circles, the animal moving around quite rapidly when
+not attached by its posterior process. It is colorless and measures
+45&micro; in length by 27&micro; in width. Clapar&egrave;de &amp; Lachmann and Shevyakov
+describe it as 70&micro; long.</p>
+
+
+<center>
+<br><a name="Chiliferidae"></a><a name="Chiliferidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to marine genera of Chiliferidæ</i>.</b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" valign="top">
+      <i>Diagnostic characters:</i> Mouth never lies behind the
+      middle of the body; the Å“sophagus is but slightly
+      developed. The undulating membranes are placed either on
+      the edge of the mouth or in the Å“sophagus. A
+      peristomial depression leading to the mouth is absent
+      or very slightly indicated.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      1.
+    </td>
+    <td width="60%" valign="top">
+      Mouth in the anterior half, undulating membrane on left edge
+      only; right edge continued in a long ventral furrow
+    </td>
+    <td valign="top">
+      Genus *<a href="#Frontonia"><i>Frontonia</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      2.
+    </td>
+    <td width="60%" valign="top">
+      Two undulating membranes; mouth central; no caudal bristles
+    </td>
+    <td valign="top">
+      Genus *<a href="#Colpidium"><i>Colpidium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      3.
+    </td>
+    <td width="60%" valign="top">
+      Two undulating membranes; caudal bristle
+    </td>
+    <td valign="top">
+      Genus *<a href="#Uronema"><i>Uronema</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Frontonia"></a>
+<br>
+<h3>Genus FRONTONIA Ehr. (Cl. &amp; Lach. '58?).</h3>
+
+<div class="center"><span class="syn">(Ehrenberg, subgenus of
+<i>Bursaria</i> '38; Clapar&egrave;de &amp; Lachmann '58;<br>
+B&uuml;tschli '88; Shevyakov '96.)</span></div>
+
+<p>Form elongate and cylindrical, or often flattened dorso-ventrally,
+with round or pointed ends. It is usually plastic and contractile.
+Cilia are evenly distributed about the body and are similar in
+length. The large, open mouth lies on the anterior half of the
+ventral surface, and is elongate and oval in outline. On its left
+edge is a well-defined membrane which stretches across to the right
+side of the mouth. On the right edge is a small, longitudinally
+striped tract which is free from trichocysts and smooth in
+appearance. This tract is continued posteriorly in a long furrow,
+which in some cases reaches the posterior end of the animal. A few
+rows of cilia in this furrow vibrate differently from the others and
+give the effect of a membrane (B&uuml;tschli). The Å“sophagus is extremely
+short and hard to make out. The body is usually covered uniformly
+with trichocysts, often of considerable size. There are 1 or 2
+vacuoles with long canals radiating throughout the endoplasm. The
+macronucleus is oval and centrally placed. Micronuclei vary from one
+to many. An anal opening is placed at the end of the long ventral
+furrow. The plasm is colorless or green by the presence of
+Zoochlorella, or colored brown or black by pigments. In these cases
+there is a considerable pigment mass on the anterior end. Movement is
+regular, forward, and combined with rotation. Food consists of
+foreign objects, diatoms, other protozoa and the like. Fresh and salt
+water.</p>
+
+
+<a name="Frontonia_leucas"></a>
+<br>
+<p class="noindent"><b>Frontonia leucas</b> Ehr.  Fig. 37.</p>
+
+<p class="syn">Synonyms: <i>Frontonia vernalis</i> Ehr. '38;
+<i>Bursaria leucas</i> Allman '55, Carter '56; <i>Panophrys
+leucas</i> Duj. '41, Stein '67; <i>Panophrys vernalis</i>
+Dujardin '41, Stein '67; <i>P. chrysalis</i> Duj. '41, Fromentel
+'74; <i>Cyrtostomum leucas</i> Stein '67, Kent '81.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_37.jpg">
+<img src="images/fig_37t.jpg" width="190" border=0
+alt="Frontonia leucas"></a>
+<br>
+<b>Fig. 37.&mdash;<br>
+<i>Frontonia leucas</i>.</b>
+<br>
+<br>
+<a href="images/fig_37.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>Form ovoid, elongate, occasionally a little flattened
+dorso-ventrally. Mouth in the anterior third of the body. The left
+edge of the mouth carries a distinct undulating membrane; the right
+edge is plain, longitudinally striated and bears cilia. It is
+slightly depressed and the depression is carried posteriorly in the
+form of a shallow furrow which reaches to the posterior end. The
+contractile vacuole is on the left side, the spheroidal nucleus on
+the right side of the furrow. The body is uniformly covered with fine
+cilia, and the periphery is uniformly studded with large trichocysts,
+except along the furrow. Food consists of dinoflagellates and other
+small forms. Color dark brown to black.</p>
+
+<p>Length 330&micro;; width 200&micro;.</p>
+
+<p>This form differs considerably from the fresh-water <i>Frontonia
+leucas</i> as described by Schewiakoff '89, especially in the extreme
+length of the peristomial furrow, in the position of the nucleus and
+contractile vacuole, and in the nature of the water canals. These in
+the Woods Hole form are very irregular in size and very much
+branched, not uniform as in Lieberk&uuml;hn's (see B&uuml;tschli) figure of
+<i>Frontonia leucas</i>, nor radiating as in Schewiakoff's description.
+This may be the same species as <i>Frontonia marina</i>, of Fabre-Domergue
+'91, whose description and figure I have not seen.</p>
+
+
+<br>
+<br><a name="Colpidium"></a>
+<br>
+<h3>Genus COLPIDIUM Stein '60</h3>
+
+<div class="center"><span class="syn">(B&uuml;tschli '88;
+Maupas '83.)</span></div>
+
+<p>The general form is oval, slightly compressed laterally with the
+dorsal side strongly arched. The ventral side is slightly incurved.
+The anterior end is somewhat smaller than the posterior end, which is
+broadly rounded. The mouth is placed some distance from the anterior
+end in an oral depression and opens into a tubular Å“sophagus. There
+are usually two undulating membranes which do not extend beyond the
+mouth borders. The right undulating membrane extends down into the
+Å“sophagus and appears to be attached to the walls of the latter. The
+body stripes in front of the mouth are twisted to the left. The anus
+is terminal and the contractile vacuole may be terminal or situated
+forwards in the dorsal region. The macronucleus is spherical and has
+one  micronucleus attached. Food consists mainly of bacteria.
+Movement rapid, but interrupted.</p>
+
+<p>Fresh and salt water, common in infusions.</p>
+
+
+<a name="Colpidium_colpoda"></a>
+<br>
+<p class="noindent"><b>Colpidium colpoda</b> Ehr., sp.  Fig. 38.</p>
+
+<p class="syn">Synonyms: <i>Colpidium cucullus</i> Kent '81; <i>C. striatus</i> Stokes '85;
+<i>Kolpoda cucullus</i> Duj. '41; <i>Paramœcium colpoda</i> Ehr. '38,
+Quennerstedt '67; <i>Plagyiopyla nasula</i> Kent '81, G. &amp; R. '86;
+<i>Glaucoma pyriformis</i> G. &amp; R. '86; <i>Tillina campyla</i> Stokes '85, '88.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_38.jpg">
+<img src="images/fig_38t.jpg" width="130" border=0
+alt="Colpidium colpoda"></a>
+<br>
+<b>Fig. 38.&mdash;<br>
+<i>Colpidium colpoda</i>.</b>
+<br>
+<br>
+<a href="images/fig_38.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The body is oval, somewhat larger posteriorly, and a little
+compressed dorso-ventrally. The anterior end is twisted a little from
+the right to the left (more evident in fresh-water forms), and leans
+somewhat toward the ventral side. Under this portion, on the ventral
+side, lies the mouth in a large depression just above the middle of
+the body. The entire body is covered with uniform and delicate cilia,
+which are placed in longitudinal rows. These rows are almost straight
+on the dorsal side, but bend on the ventral surface, following the
+contour of the twisted anterior portion. The endoplasm is finely
+granular; the Å“sophagus leading into it is very distinct.
+Schewiakoff ('89) describes two membranes, an inner and an outer;
+Maupas ('83) describes them as right and left. In the present species
+I was able to make out only one. The macronucleus is central,
+spherical in form, and bears a single minute micronucleus. The
+contractile vacuole is posterior and dorsal to the long axis of the
+body. The anus is ventral to this axis and also posterior. Length
+45&micro;, width 20&micro;. Common.</p>
+
+<p>This marine variety is much smaller than the fresh-water form and the
+form differs in a number of respects, viz, in the anterior torsion
+and in the structure of the mouth. These may be, however, only
+individual variations of a widely spread species, and I believe it is
+perfectly safe to describe this as <i>Colpidium colpoda</i>.</p>
+
+<br>
+<br><a name="Uronema"></a><a name="Uronema1"></a>
+<br>
+<h3>Genus URONEMA Duj. '41.</h3>
+
+<div class="center"><span class="syn">(Quennerstedt '69; Cohn '66;
+Kent '81; B&uuml;tschli '81; Schewiakoff '89;
+Shevyakov '96.)</span></div>
+
+
+<p>Minute forms; colorless and constant in body form. The form is oval,
+slightly compressed on the ventral side, while the dorsal side is
+distinctly arched. The membrane is distinctly marked by rather widely
+separated striæ. These occasionally have a spiral course about the
+body; in all cases they can be easily counted. The mouth is large and
+placed near the center of the ventral surface. It is sometimes
+approached by a very shallow depression or peristome from the
+anterior end, and marked by two rows of cilia. An undulating membrane
+extends down the mouth. Oesophagus absent. A long, stiff bristle
+extends outwards from the posterior end. The contractile vacuole is
+terminal or subterminal and near the anal opening. The macronucleus
+is spherical, centrally placed, and with one micronucleus closely
+applied. Movement is rapid and usual forwards in a straight line,
+often found resting, however, with outstretched cilia in contact with
+some foreign body. Food mainly bacteria. Fresh and saltwater, usually
+in decomposing vegetable substances.</p>
+
+
+<a name="Uronema_marina"></a><a name="Uronema_marina1"></a>
+<br>
+<p class="noindent"><b>Uronema marina</b> Duj.  Fig. 39.</p>
+
+<p class="syn">Synonyms: <i>Enchelys triquetra</i> Dujardin;
+<i>E. corrugata</i> Duj.;
+<i>Cryptochilum griseolum</i> Maupas '83; <i>Philaster digitiformis</i>
+Fabre-Domergue '85.</p>
+
+
+<p>Small animals with ellipsoidal form and about twice as long as broad.
+The mouth lies in the upper half of the body and bears a
+well-developed undulating membrane upon its left edge. The membrane
+is longitudinally striped and covered with long and vibratile cilia.
+The right edge of the mouth bears cilia which are about the same in
+size as the body cilia, but are more closely inserted (Schewiakoff).
+The most characteristic feature is the long caudal bristle, which is
+extremely delicate and about two-thirds the length of the body.
+Schewiakoff thinks this bristle has a sensory function. I could not
+make this out, for although other protozoa ran against this bristle,
+often bending it well over to one side, the animal showed no sign of
+irritability but lay quiescent. A spherical macronucleus with
+attached micronucleus lies in the center of the body. The contractile
+vacuole is posterior in front of the bristle. The macronucleus was
+found to be double, as though just divided, in a large percentage of
+cases. This may be a precocious division of the nucleus long before
+signs of the body division are evident. Such a phenomenon, however,
+is rare, the macronucleus usually dividing at a late stage of cell
+division. Length 30 to 50&micro;; width 15 to 20&micro;. Common in decomposing
+algæ.</p>
+
+
+<center>
+<table class="imagetable"><tr><td align="center">
+<a href="images/fig_39.jpg">
+<img src="images/fig_39t.jpg" width="130" border=0
+alt="Uronema marina"></a>
+</td><td align="center">
+<b>Fig. 39.&mdash;<br>
+<i>Uronema marina</i>.</b>
+<br>
+<br>
+<a href="images/fig_39.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<center>
+<br><a name="Pleuronemidae"></a><a name="Pleuronemidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="2" align="center">
+      <b><i>Key to marine genera of Pleuronemidæ</i>.</b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" valign="top">
+      <i>Diagnostic characters:</i> The mouth is at the end of a
+      long peristome running along the ventral side; the body is
+      dorso-ventrally or laterally compressed. The entire left
+      edge of the peristome is provided with an undulating
+      membrane which occasionally runs around the posterior end
+      of the peristome to form a "pocket" leading to the mouth.
+      The right edge of the peristome is provided with a
+      less-developed membrane. There may or may not be a
+      well-developed pharynx.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Body small; not produced into neck-like elongation
+    </td>
+    <td valign="top">
+      Genus *<a href="#Pleuronema"><i>Pleuronema</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Body medium-sized; anterior end produced into neck-like
+      elongation
+    </td>
+    <td valign="top">
+      Genus *<a href="#Lembus"><i>Lembus</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Pleuronema"></a>
+<br>
+<h3>Genus PLEURONEMA Dujardin '41.</h3>
+
+<div class="center"><span class="syn">(Perty '52; Clap. &amp;
+Lach. '58; Stein '59, vol. I; Quennerstedt '67;<br>
+Kent '81;
+B&uuml;tschli '88; Schewiakoff '89; Shevyakov '96.)</span></div>
+
+<p>Small to medium-sized ciliates, with an unchanging form. They are
+somewhat lens-shape and laterally compressed, the two surfaces about
+equally arched. The ventral surface is nearly straight or but
+slightly arched; the dorsal is quite convex.  The anterior and
+posterior extremities are equally rounded.  The peristome begins as a
+small depression, but becomes larger until it takes in nearly all of
+the ventral surface. The depression becomes much deeper at about the
+center of the body, and is especially marked on the left side of the
+peristome. In this deeper portion is the mouth, with an almost
+imperceptible Å“sophagus. Upon the left edge of the peristome is a
+high, undulating membrane, sail-like in appearance when extended.
+This may stretch around the posterior edge of the peristome and upon
+the right aide, thus forming a pocket by means of which the food
+particles are directed into the mouth. The rest of the right edge of
+the peristome is occupied by closely approximated powerful cilia
+(B&uuml;tschli) or a second undulating membrane (Stein). The body cilia
+are relatively long. Trichocysts and caudal bristles may be present.
+The contractile vacuole is subterminal and dorsal; it is questionable
+whether there are canals leading to it. A round macronucleus with one
+micronucleus is in the anterior half of the body. The anus is
+terminal. Food is chiefly bacteria. Movement combines springing with
+swimming and rotation. Fresh and salt water.</p>
+
+
+<a name="Pleuronema_chrysalis"></a>
+<br>
+<p class="noindent"><b>Pleuronema chrysalis</b> Ehr., sp.  Fig. 40.</p>
+
+<p class="syn">Synonyms: <i>Pleuronema crassa</i> Dujardin '41;
+<i>P. marina</i> Duj. '41; Fabre-Domergue '85; <i>P. coronata</i>
+Kent '81; <i>Paramœcium chrysalis</i> Ehr. '38; <i>Lembadion
+orale</i> G. &amp; R. '88; <i>Histiobalantium agile</i>
+Stokes '85, '88.</p>
+
+<p>The body is ovoid, slightly flattened, rounded at both ends, the
+anterior end sharper than the posterior. The ventral surface is
+almost entirely taken up by a peristome which extends from the
+anterior end posteriorly three-quarters of the body length. The
+posterior end of the peristome is straight, the left curved,
+following the depressed portion. The body is covered with fine cilia
+in longitudinal lines, except on the peristome. The mouth is small
+and situated in the hollow of the peristome near the left border. On
+the left peristome edge is a large undulating membrane. It begins
+near the anterior end of the body and increases in height posteriorly
+following the peristome edge around on the right side. This posterior
+bend of the membrane causes the appearance of a full sail, so often
+seen. It can be entirely withdrawn and folded together in the
+peristome. On the right edge of the peristome are large, powerful
+cilia. The contractile vacuole is central and dorsal; the
+macronucleus is in the anterior half of the body, with one attached
+micronucleus. Food consists of bacteria. Not very common. Fresh and
+salt water. It often remains quiet, with membrane and cilia
+outstretched, as though dead, but suddenly gives a spring and is
+gone.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_40.jpg">
+<img src="images/fig_40t.jpg" width="340" border=0
+alt="Pleuronema chrysalis"></a>
+</td><td align="center">
+<b>Fig. 40.&mdash;<br>
+<i>Pleuronema chrysalis</i>.</b>
+<br>
+<br>
+<a href="images/fig_40.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Pleuronema_setigera"></a>
+<br>
+<p class="noindent"><b>Pleuronema setigera</b>, n. sp.  Fig. 41.</p>
+
+<p>Body colorless, elongate, and with the general form of a cucumber,
+the posterior end being somewhat pointed. The mouth and relatively
+small peristome are situated in the lower third of the body. The
+peristome begins as a shallow furrow at the center of the ventral
+surface and dips sharply into the buccal depression, which is deep
+and turned toward the posterior end. The left edge of the peristome
+bears a high undulating membrane, which extends anteriorly only as
+far as the center of the body; posteriorly it passes around to the
+right edge of the peristome, thus forming the characteristic
+membranous pocket. Inside the oral depression is a second undulating
+membrane, running down to the mouth. This is small and without an
+Å“sophagus. The body is clothed with long setose cilia which are
+frequently fully outstretched when the animal is resting, a slight
+tremor of the large membrane alone indicating vitality. Posteriorly
+these appendages are drawn out into long filiform setæ, the number
+varying in different individuals from three to nine or ten. These are
+extremely fine and difficult to see without a high power (<i>e.g.</i> 1/12
+oil) and careful focussing of the substage condensor. Like <i>P.
+chrysalis</i>, the resting periods are terminated by sudden springs,
+otherwise the movements are steady and forward. The macronucleus is
+central, and the contractile vacuole posterior and terminal. Length
+45&micro; to 50&micro;; greatest diameter 17&micro;. In decaying algæ.</p>
+
+<p>It was this form, I believe, that Peck '95 described as a "ciliate."</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_41.jpg">
+<img src="images/fig_41t.jpg" width="400" border=0
+alt="Pleuronema setigera"></a>
+</td><td align="center">
+<b>Fig. 41.&mdash;<br>
+<i>Pleuronema setigera</i>.</b>
+<br>
+<br>
+<a href="images/fig_41.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Lembus"></a>
+<br>
+<h3>Genus LEMBUS Cohn '66.</h3>
+
+<div class="center"><span class="syn">(Cohn '66; Quennerstedt '69;
+Kent '81; Fabre-Domergue '85;<br>
+Gourret &amp;
+Roeser '88; B&uuml;tschli '88; Shevyakov '96.)</span></div>
+
+<p>Free-swimming animals of elongate form, more or less elastic, and
+flexible, bending readily to avoid obstacles, etc. The anterior half
+is usually drawn out into a slightly curved neck-like portion. The
+peristome is a small groove leading from the anterior end to the
+mouth about midway down the ventral side of the body. B&uuml;tschli,
+following Quennerstedt, describes an undulating membrane on each side
+of the peristome groove. Other observers, however, usually describe
+but one, the left, which is clearly defined and stretches out some
+distance from the body, while the right border is described as having
+smaller but very active cilia. The general body surface is clothed
+with fine, uniform cilia, and body striæ are usually absent. One or
+more caudal bristles may be present. The contractile vacuole is
+posterior and terminal, and may be multiple. The macronucleus is
+spherical and perhaps double (Kent). Food is chiefly bacteria, and
+the animals are frequently found with the anterior end embedded in
+zooglœa masses. Salt water, usually in infusions.</p>
+
+
+<a name="Lembus_infusionum"></a>
+<br>
+<p class="noindent"><b>Lembus infusionum</b>, n. sp. Fig. 42.</p>
+
+<p>The body is elongate, lancet-shaped, with a tapering anterior
+extremity. The dorsal outline is concave through the bending of the
+anterior end, while the ventral outline presents an even, convex
+curve. The mouth lies slightly above the center of the body and marks
+the posterior limit of the ventral peristomial groove, which curves
+slightly from the anterior extremity. Each side of this groove bears
+an undulating membrane, the left being much larger and conspicuously
+striated. The general form of this left membrane is triangular, the
+widest part is anterior, the narrowest at the mouth. The right
+membrane is similar in form, but smaller and more active. The
+endoplasm is colorless and finely granular, not regionally
+differentiated. The ectoplasm consists of a relatively thick cortical
+plasm specially noticeable in the posterior half of the body and a
+delicate cuticle which bears almost imperceptible longitudinal
+markings&mdash;the insertion points of the fine cilia. The body is covered
+with uniform cilia except at the anterior extremity. Here they are
+much larger and bristle-like. I was unable to find any cilia in the
+peristome. One long caudal bristle, one-quarter of the length of the
+body, trails out behind. The macronucleus is spheroidal and placed
+near the center of the body; a conspicuous micronucleus lies near it.
+A row of contractile vacuoles extends from the posterior end. I have
+seen as many as six of nearly equal size and one or two smaller ones.
+The intervals of contraction are quite long. Length 70 to 75&micro;;
+greatest diameter 10 to 12&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_42.jpg">
+<img src="images/fig_42t.jpg" width="500" border=0
+alt="Lembus infusionum"></a>
+<br>
+<b>Fig. 42.&mdash;<i>Lembus infusionum</i>.</b>
+<br>
+<br>
+<a href="images/fig_42.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p><i>L. infusionum</i> resembles <i>L. elongatus</i> in its general form and in
+its mode of life, for it excavates a retreat in zooglœa masses and
+lies there for considerable periods perfectly quiet. It differs from
+<i>L. elongatus</i> and from <i>L. velifer</i> (probably the same as <i>L.
+elongatus</i> of Clapar&egrave;de &amp; Lachmann) in the presence of the caudal
+bristle, in the absence of annular markings, number of contractile
+vacuoles, and in the slightly smaller size. It resembles <i>Lembus
+verminus</i> (M&uuml;ller) as described by Kent (<i>Proboscella vermina</i>), and
+<i>L. intermedius</i> as described by Gourret &amp; Roeser (<i>Lembus verminus</i>
+syn.)in the absence of annular markings and in the presence of a
+caudal bristle. It differs from the former, however, in the absence
+of a tentacle-like process, and from both in the absence of a double
+nucleus and in the presence of many vacuoles. These features are so
+characteristic of all the specimens examined that I have concluded,
+somewhat reluctantly, to give it a specific name. It is common in old
+infusions of algæ, especially after decomposition is well advanced.
+Its food consists of bacteria.</p>
+
+
+<a name="Lembus_pusillus"></a>
+<br>
+<p class="noindent"><b>Lembus pusillus</b> Quennerstedt 1869.  Fig. 43.</p>
+
+<p class="syn">Synonym: <i>L. subulatus</i> Kent 81.</p>
+
+<p>This species is much smaller than the preceding, and might easily be
+mistaken for <a href="#Uronema_marina1"><i>Uronema marina</i></a>.
+It is subcylindrical in form, the
+anterior end bluntly pointed, the posterior end rounded. The oral
+apparatus is quite different from
+<a href="#Uronema1"><i>Uronema</i></a>. The mouth, as in the
+preceding species, is at the end of a long peristomial groove
+extending from the anterior end to the middle of the body. The edges
+of the peristome bear undulating membranes as in <i>L. infusionum</i>.
+Like the latter, there is one caudal bristle, but unlike it there is
+only one posterior contractile vacuole, while the endoplasm is filled
+with large granules or food balls. The cuticle is distinctly striated
+with longitudinal markings, and the cilia are uniform in length.</p>
+
+<p>Habitat similar to that of <i>L. infusionum</i>, in zooglœa masses.
+Length 26 to 30&micro;; diameter 7 to 8&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_43.jpg">
+<img src="images/fig_43t.jpg" width="500" border=0
+alt="Lembus pusillus"></a>
+<br>
+<b>Fig. 43.&mdash;<i>Lembus pusillus</i>.</b>
+<br>
+<br>
+<a href="images/fig_43.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p>Although Quennerstedt's description of <i>L. pusillus</i> makes no mention
+of a caudal bristle, the size and other characters are so closely
+similar that I hesitate to make a new species. The bristle is
+extremely delicate, scarcely thicker than a cilium, and easily
+overlooked, yet with proper focussing of the condenser I found it on
+every specimen examined.</p>
+
+
+<center>
+<a name="Opalinidae"></a><a name="Opalinidae1"></a><a name="Opalinidae2"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="2" align="center">
+      <b><i>Key to marine genera of Opalinidæ</i>.</b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" valign="top">
+      <i>Diagnostic characters:</i> The form is oval, and
+      the body may be short or drawn out to resemble a worm.
+      They are characterized mainly by the absence of mouth
+      and pharynx.
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Anterior end not pointed; body cylindrical; tapering
+    </td>
+    <td valign="top">
+      Genus *<a href="#Anoplophrya"><i>Anoplophrya</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="65%" valign="top">
+      Anterior end pointed; body elongate; cylindrical; tapering
+    </td>
+    <td valign="top">
+      Genus <i>Opalinopsis</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Anoplophrya"></a>
+<br>
+<h3>Genus ANOPLOPHRYA Stein '60.</h3>
+
+<div class="center"><span class="syn">(Stein '60;
+Clapar&egrave;de '60; Leidy '77; Vejdovsky '79;<br>
+Kent '81; Balbiani '85; B&uuml;tschli '88;
+Shevyakov '96.)</span></div>
+
+<p>The general form is elongate, cylindrical or slightly flattened, with
+rounded ends, the posterior end tapering. The body is striated with
+clearly defined, often depressed lines, which run longitudinally and
+sometimes spirally. The contractile vacuoles are usually placed in
+rows upon the edges. The macronucleus is almost always long and
+band-formed, rarely oval, and generally extending through the entire
+length of the body. Micronuclei have been made out in one case.
+Reproduction is effected by simple cross division or by budding at
+the posterior end, and is frequently combined with chain formation.
+The main characteristic is the entire absence of mouth and
+Å“sophagus, the animals being parasitic in the digestive tract of
+various annelids. Parasites, salt-water forms.</p>
+
+
+<a name="Anoplophrya_branchiarum"></a>
+<br>
+<p class="noindent"><b>Anoplophrya branchiarum</b>. Stein '52.  Fig. 44.</p>
+
+<p class="syn"><i>A. circulans</i> Balbiani.</p>
+
+<p>The body is cylindrical to pyriform, in the latter case broadened
+anteriorly. Cuticle distinctly marked by longitudinal striations
+which take the form of depressions and give to the body a
+characteristic melon shape. The endoplasm contains a number of large
+refringent granules&mdash;probably body products. The nucleus is elongate,
+somewhat curved, and coarsely granular. A micronucleus lies in the
+concavity. The cilia are long, inserted rather widely apart along the
+longitudinal markings. The contractile vacuole is single and is
+located at the pointed end, which is directed backwards during
+locomotion. One specimen found free swimming among some algæ.</p>
+
+<p>Length 104&micro;; greatest diameter 36&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_44.jpg">
+<img src="images/fig_44t.jpg" width="400" border=0
+alt="Anoplophrya branchiarum"></a>
+<br>
+<b>Fig. 44.&mdash;<i>Anoplophrya branchiarum</i>.</b>
+<br>
+<br>
+<a href="images/fig_44.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p>I was much surprised to find this form swimming about freely in the
+water; its mouthless condition showed it to belong to the family of
+parasites, the <a href="#Opalinidae"><i>Opalinidæ</i></a>.
+As the name indicates, however, this
+species is an ectoparasite upon the gills, and Stein gave the name
+<i>branchiarum</i> to a fresh-water form parasitic upon <i>Gammarus pulex</i>.
+The Woods Hole form is so strikingly similar to the figure of <i>G.
+branchiarum</i> that, although the name was given to a fresh-water form,
+it obviously applies to this marine variety. One important difference
+is the presence of only one contractile vacuole in the marine form.</p>
+
+
+<center>
+<br><a name="Heterotrichida"></a><a name="Heterotrichida1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="4" align="center">
+      <b><i>Key to families of Heterotrichida.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      Cilia cover the body
+    </td>
+    <td>
+      1
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      Cilia reduced to certain localized areas
+    </td>
+    <td>
+      2
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      1.
+    </td>
+    <td colspan="3" valign="top">
+      <i>Polytrichina</i>.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top">
+      The mouth terminates a long peristomial furrow having an
+      adoral zone along the entire left edge
+    </td>
+    <td valign="top">
+      Family <a href="#Plagiotomidae"><i>Plagiotomidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top">
+      Peristomial area a broad triangular area ending in mouth
+    </td>
+    <td valign="top">
+      Family <a href="#Bursaridae"><i>Bursaridæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="55%" valign="top">
+      Peristomial depression short; limited to the anterior end; its
+      plane at right angles to the long axis of body; surface of
+      peristome striated and ciliated; no undulating membranes
+    </td>
+    <td valign="top">
+      Family <a href="#Stentoridae"><i>Stentoridæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      2.
+    </td>
+    <td colspan="3" valign="top">
+      <i>Oligotrichina</i>.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="55%" valign="top">
+      Peristome without cilia; cilia limited to one or more
+      girdles about body
+    </td>
+    <td valign="top">
+      Family <i>Halteriidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="2" valign="top">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      One marine genus
+    </td>
+    <td valign="top">
+      *<a href="#Strombidium"><i>Strombidium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="55%" valign="top">
+      Thecate forms; the body is attached by a stalk to the cup;
+      within the adoral zone is a ring of cilia.
+    </td>
+    <td valign="top">
+      Family <a href="#Tintinnidae"><i>Tintinnidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="55%" valign="top">
+      The peristomial depression is deep and funnel-like; cuticle
+      thick, with posterior spine-like processes.
+    </td>
+    <td valign="top">
+      Family <i>Ophryoscolecidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+<br><a name="Plagiotomidae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to the marine genera of Plagiotomidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      <i>Diagnostic characters:</i> The peristome is a narrow
+      furrow which begins, as a rule, close to the anterior
+      end and runs backward along the ventral side, to the
+      mouth, which is usually placed between the middle of
+      the body and the posterior end. A well-developed adoral
+      zone stretches along the left side of the peristome,
+      and is usually straight.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      1.
+    </td>
+    <td width="60%" valign="top">
+      Body cylindrical; size medium; peristome long and turns
+      sharply to the left at the extremity
+    </td>
+    <td valign="top">
+      Genus <i>Metopus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      2.
+    </td>
+    <td width="60%" valign="top">
+      No torsion in the peristome; undulating membrane is
+      confined to the posterior part of peristome
+    </td>
+    <td valign="top">
+      Genus <i>Blepharisma</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      3.
+    </td>
+    <td width="60%" valign="top">
+      No peristomial torsion; body highly contractile;
+      no undulating membrane
+    </td>
+    <td valign="top">
+      Genus <i>Spirostomum</i>
+    </td>
+  </tr>
+</table>
+<br><a name="Bursaridae"></a><a name="Bursaridae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to the marine genera of Bursaridæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      <i>Diagnostic characters:</i> The body is usually short
+      and pocket-like, but may be elongate. The chief
+      characteristic is the peristome, which is not a furrow,
+      but a broad triangular area deeply insunk and ending in
+      a point at the mouth. The adoral zone is usually
+      confined to the left peristome edge, or it may cross
+      over to the right anterior edge.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      1.
+    </td>
+    <td width="60%" valign="top">
+      The anterior half of the body tapers to nearly a point in
+      front; the peristome is narrowest at the apex; the mouth
+      is the entire peristome base.
+    </td>
+    <td valign="top">
+      Genus <i>Balantidium</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      2.
+    </td>
+    <td width="60%" valign="top">
+      The anterior end does not taper; the peristome is widest
+      at the end of the body; the mouth is clearly defined.
+    </td>
+    <td valign="top">
+      Genus *<a href="#Condylostoma"><i>Condylostoma</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Condylostoma"></a>
+<br>
+<h3>Genus CONDYLOSTOMA<br>
+(KONDYLOSTOMA Bory de St. Vincent 1824) Dujardin
+'41</h3>
+
+<div class="center"><span class="syn">(Dujardin '41;
+Clapar&egrave;de &amp; Lachmann '58; Stein '59, '67; Cohn '66;
+Quennerstedt '67;<br>
+Wrzesniowski '70; B&uuml;tschli '76, '88; Kent '81;
+Maupas '83; Shevyakov '96.)</span></div>
+
+<p>Colorless and more or less flexible animals of medium size. The
+general form is elongate and cylindrical or somewhat smaller
+anteriorly. The posterior end is broadly rounded, the anterior end
+somewhat truncate and oblique. The peristome is broad and triangular,
+the base of the triangle being the entire anterior end of the body.
+The entire length of the peristome is one-fourth or less of the body
+length. The mouth is large and placed at the apex of the peristomial
+triangle and opens into a comparatively small Å“sophagus. The right
+edge of the peristome is lamellate and bears a clearly defined
+undulating membrane. The adoral zone is well developed upon the left
+edge of the peristome, from which it passes around anteriorly to the
+right edge. The surface of the peristome is free from cilia, but the
+rest of the body is uniformly coated with small active cilia.
+Contractile vacuoles are not safely determined. B&uuml;tschli thinks there
+is probably one terminal vacuole, but some observers deny this
+(<i>e.g.</i> Maupas). Others describe them on the dorsal side of the
+posterior end (Quennerstedt). The macronucleus is long and beaded and
+placed upon the right side. Micronuclei are numerous and scattered
+along the macronucleus. The anus is terminal and dorsal. Food
+consists of large and small particles. Movement rapid, free swimming,
+alternating with resting periods; in some cases an undulating or
+wriggling movement is seen, showing clearly the flexibility of the
+body. Fresh and salt water.</p>
+
+
+<a name="Condylostoma_patens"></a>
+<br>
+<p class="noindent"><b>Condylostoma patens</b> M&uuml;ller.  Fig. 45.</p>
+
+<p>The body is elongate, somewhat sac-like, five or six times as long as
+broad, plastic, and frequently contains brightly colored food
+granules. The triangular peristome takes up the greater part of the
+anterior end, and the mouth is situated at the sharper angle of the
+triangle, about one-fourth of the total length from the anterior end.
+The cuticle is longitudinally striated, the lines having a slightly
+spiral course. They are not closely set, and fine cilia are thickly
+inserted along their edges. The endoplasm is granular and viscous.
+The motile organs consist of an adoral zone of membranelles, which
+stretch along the left edge of the peristome and the front edge of
+the body. The right edge of the peristome supports an undulating
+membrane. The nucleus is moniliform and extends the full length of
+the left side; a number of micronuclei are distributed along its
+course (Maupas).</p>
+
+<p>Length 400&micro;; diameter at widest part 105&micro;. Maupas gives the length
+from 305&micro; to 495&micro;; and Stein 376&micro; to 564&micro;. Very common.</p>
+
+<p>For a more extended account of the structures, see the excellent
+description by Maupas '83.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_45.jpg">
+<img src="images/fig_45t.jpg" width="450" border=0
+alt="Condylostoma patens"></a>
+<br>
+<b>Fig. 45.&mdash;<i>Condylostoma patens</i>.</b>
+<br>
+<br>
+<a href="images/fig_45.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<center>
+<br><a name="Stentoridae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to the marine genera of Stentoridæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      <i>Diagnostic characters:</i> The peristome is
+      relatively short and limited to the front end of the
+      animal, so that its plane is nearly at right angles to
+      that of the longitudinal axis of the body. The adoral
+      zone of cilia either passes entirely around the
+      peristome edge or ends at the right-hand edge. The
+      surface of the peristome is spirally striated and
+      provided with cilia. Undulating membranes are absent.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      1.
+    </td>
+    <td width="60%" valign="top">
+      Peristome circular in outline; limited to the anterior end
+    </td>
+    <td valign="top">
+      Genus <i>Stentor</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      2.
+    </td>
+    <td width="60%" valign="top">
+      The peristome is drawn out into two wing-like processes;
+      tube-dwelling
+    </td>
+    <td valign="top">
+      Genus <i>Folliculina</i>
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Strombidium"></a>
+<br>
+<h3>Genus STROMBIDIUM Cl. &amp; Lach. '58.</h3>
+
+<div class="center"><span class="syn">(Stein '67;
+B&uuml;tschli '73; Fromentel '74; Kent '81;<br>
+Gruber '84; Entz '84; Maupas '83. B&uuml;tschli '88.)</span></div>
+
+<p>Small, colorless (except for ingested food) animals with
+characteristic springing movements. The form is usually constant, but
+in some cases may be plastic like <i>Astasia</i>; it is usually globular
+or conical, the posterior end being more or less pointed, the
+anterior end broadest. The latter is surrounded by a complete circle
+of the adoral zone, the oral end of which passes into a peristomial
+depression which extends deep into the middle of the body. The mouth,
+with a very small Å“sophagus, lies at the bottom of the inturned
+peristome. The region surrounded by the adoral zone is frequently
+drawn out into an anterior process, occasionally bearing a pigment
+mass. The ventral surface in some cases bears cilia, which may be
+distributed or restricted to a row of large cilia. Trichocysts are
+usually present and may be widely spread, limited to the posterior
+region, or arranged in a girdle about the middle. The contractile
+vacuole is simple, and posterior in position. The macronucleus is
+spherical and usually central in position. Movement is rapid
+swimming, combined with resting and floating periods, the latter
+usually terminated by a sudden leap.</p>
+
+<p>Fresh and salt water; more common in the latter.</p>
+
+
+<a name="Strombidium_caudatum"></a>
+<br>
+<p class="noindent"><b>Strombidium caudatum</b> Fromentel '74.  Fig. 46, a, b, c.</p>
+
+<p>Fromentel described a fresh-water form of this genus with a caudal
+appendage. The body is pyriform, broadly truncate on the anterior
+end, in the middle of which rises a papilliform process (Schnabel).
+On this process is a heap of pigment granules, which, however, are
+not constant. A ring of long cirri surround the anterior end and pass
+into the peristome, and from the left edge of this line of cirri a
+large adoral zone continues down to the mouth. The peristome is
+elongate and sac-form, and the mouth lies at the posterior extremity.
+With the exception of a caudal filament there are no other motile
+organs; this is about half as long as the body, structureless,
+hyaline, and sharply pointed. It splits up into a bundle of fine
+fibers upon treatment with caustic potash (c). The cirri emerge from
+minute hollows in the edge of the anterior border. The cortical plasm
+contains peculiar rod-like bodies, which look more like lines or
+markings than like rods or trichocysts. The nucleus is large,
+spherical, and placed in the center of the body. The contractile
+vacuole is posterior.</p>
+
+<p>Length without appendage is about 35&micro;; greatest diameter 15 to 18&micro;.
+In decaying vegetable matter. Common.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_46.jpg">
+<img src="images/fig_46t.jpg" width="500" border=0
+alt="Strombidium caudatum"></a>
+<br>
+<b>Fig. 46.&mdash;<i>Strombidium caudatum</i>.</b>
+<br>
+<br>
+<a href="images/fig_46.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p>Although Fromentel's species is incompletely described, it is very
+evident that the organism corresponds fairly well with the Woods Hole
+variety. His was a fresh-water type; this is marine, but the caudal
+filament and the contractile vacuole are similar. Certainly in this
+case the organism can not be regarded as a Vorticella broken off its
+stalk, as Kent '81 suspected. The anterior process with its pigment
+spot; the cirri, the spherical nucleus, the position of the vacuole,
+etc., are all opposed to such an interpretation which Kent applied to
+the original species. Neither can it be a Tintinnoid. I place it
+provisionally as <i>S. caudatum</i>.</p>
+
+
+<center>
+<br><a name="Tintinnidae"></a><a name="Tintinnidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to the marine genera of Tintinnidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="left">
+      <i>Diagnostic characters:</i> Body attached by a stalk to a
+      cup. Inside the zone of membranelles is a ring of cilia
+      (par-oral).
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      1.
+    </td>
+    <td width="60%" valign="top">
+      The test is gelatinous and more or less covered by
+      foreign particles
+    </td>
+    <td valign="top">
+      Genus <i>Tintinnidium</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      <a name="Tintinnus"></a>
+      2.
+    </td>
+    <td width="60%" valign="top">
+      The test is chitinous and clear. No foreign particles.
+    </td>
+    <td valign="top">
+      Genus <i>Tintinnus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      3.
+    </td>
+    <td width="60%" valign="top">
+      The test is chitinous; covered by foreign particles,
+      growth rings frequent
+    </td>
+    <td valign="top">
+      Genus *<a href="#Tintinnopsis"><i>Tintinnopsis</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      4.
+    </td>
+    <td width="60%" valign="top">
+      The test is chitinous, often covered by foreign particles.
+      The test is marked by discoid, circular, or hexagonal spots.
+    </td>
+    <td valign="top">
+      Genus <i>Codonella</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      5.
+    </td>
+    <td width="60%" valign="top">
+      The test is perforated by pores of circular or hexagonal form.
+    </td>
+    <td valign="top">
+      Genus <i>Dictyocysta</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+</table>
+</center>
+
+
+<br>
+<br><a name="Tintinnopsis"></a>
+<br>
+<h3>Genus TINTINNOPSIS Stein '67.</h3>
+
+<div class="center"><span class="syn">(Stein '67; Kent '81;
+Daday '87; B&uuml;tschli '88.)</span></div>
+
+<p>Medium-sized ciliates, inclosed in a chitinous lorica with embedded
+sand crystals. The form of the house, or lorica, varies greatly. In
+some cases the mouth opening is wide, giving the lorica a bell form;
+it may be long and tubular, short and spherical, or variously
+indented. The animal is attached, as in the closely allied genus
+<a href="#Tintinnus"><i>Tintinnus</i></a>, by a peduncle
+to the bottom of the lorica. The anterior
+end of the animal is inclosed by two complete circles of cilia; one,
+the outer, forming the adoral zone, is composed of thick
+tentacle-like membranelles, the other consists of shorter cilia
+within the adoral zone. The mouth leads into a curved Å“sophagus
+containing rows of downward-directed cilia (Daday). The entire body
+is covered with cilia, but as the lorica is always opaque these can
+be made out only when the animal is induced to leave the house. The
+only difference between this genus and <i>Tintinnus</i> is the covering of
+foreign bodies&mdash;usually sand crystals. Movement is rapid and
+restless, and peculiarly vibratory, owing to the apparent awkwardness
+in moving the house.  Salt water.</p>
+
+
+<a name="Tintinnopsis_beroidea"></a>
+<br>
+<p class="noindent"><b>Tintinnopsis beroidea</b> Stein,
+var. plagiostoma Daday.  Fig. 47.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_47.jpg">
+<img src="images/fig_47t.jpg" width="200" border=0
+alt="Tintinnopsis beroidea"></a>
+<br>
+<b>Fig. 47.&mdash;<br>
+<i>Tintinnopsis beroidea</i>.</b>
+<br>
+<br>
+<a href="images/fig_47.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+<p class="syn">Synonym: <i>Codonella beroidea</i> Entz '84.</p>
+
+<p>The shell is colorless, thimble-shaped, with a broadly rounded
+posterior end. The body is cylindrical. The internal organs were not
+observed. Membranelles 24 in number. Length 50&micro;; greatest diameter
+40&micro;.</p>
+
+
+<br>
+<p class="noindent">Var. compressa Daday '87.</p>
+
+<p>The posterior end of the shell is pointed, the lower third of the
+shell is swollen, the upper third is uniform in diameter and without
+oral inflation or depression. Nucleus not seen.</p>
+
+<p>Length 70&micro;; greatest diameter 48&micro;.</p>
+
+
+<a name="Tintinnopsis_davidoffi"></a>
+<br>
+<p class="noindent"><b>Tintinnopsis davidoffi</b> Daday.  Fig. 48.</p>
+
+<p>The shell is large, elongated, and provided with a considerable
+spine. The chitin of the shell is covered with silicious particles of
+diverse size. The internal structures were not observed.</p>
+
+<p>Length of shell and spine 230&micro;; diameter of the oral aperture 54&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_48.jpg">
+<img src="images/fig_48t.jpg" width="400" border=0
+alt="Tintinnopsis davidoffi"></a>
+<br>
+<b>Fig. 48.&mdash;<i>Tintinnopsis davidoffi</i>.</b>
+<br>
+<br>
+<a href="images/fig_48.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p>The variations of these species are considerable, and as the internal
+structures, such as the nucleus, are essential in fixing their
+systematic position, I place them as above, provisionally, and until
+further observations can be made.</p>
+
+
+<center>
+<br><a name="Hypotrichida"></a><a name="Hypotrichida1"></a><a name="Peritromidae"></a><a name="Peritromidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to families of Hypotrichida.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      a.
+    </td>
+    <td width="60%" valign="top">
+      Peristome indistinct; cilia on ventral surface uniform
+      and not differentiated into cirri
+    </td>
+    <td valign="top">
+      Family <i>Peritromidæ</i><br>
+      One genus, *<a href="#Peritromus"><i>Peritromus</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      b.
+    </td>
+    <td width="60%" valign="top">
+      Peristome more or less indistinct; cilia reduced to a few
+      rows on the ventral surface; anal and frontal cirri present
+    </td>
+    <td valign="top">
+      Family <a href="#Oxytrichidae1"><i>Oxytrichidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      c.
+    </td>
+    <td width="60%" valign="top">
+      Cilia entirely reduced; frontal and anal cirri present or
+      reduced; macronucleus band-formed or spherical
+    </td>
+    <td valign="top">
+      Family <a href="#Euplotidae1"><i>Euplotidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      d.
+    </td>
+    <td width="60%" valign="top">
+      Peristome reduced to left edge and does not reach over the
+      anterior margin
+    </td>
+    <td valign="top">
+      Family <i>Aspidiscidæ</i><br>
+      One genus, *<a href="#Aspidisca"><i>Aspidisca</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+</table>
+</center>
+
+
+<br>
+<br><a name="Peritromus"></a>
+<br>
+<h3>Genus PERITROMUS Stein '62.</h3>
+
+<div class="center"><span class="syn">(Stein '62, '67;
+Maupas '83.)</span></div>
+
+<p>The body is flat, colorless or tinged with yellow, and contractile.
+It is elliptical in outline, with broadly rounded ends; in some cases
+the left edge is slightly incurved, the right edge convex. The
+ventral surface is flat, the dorsal surface is arched in the middle
+region of the body. The edges being flat are somewhat more
+transparent than the remainder of the body. The ventral surface is
+striated by longitudinal straight or slightly curved lines, the
+dorsal surface is smooth and without cilia. (Maupas describes
+bristles on the back, but this is not corroborated.) The adoral zone
+is fairly well developed, but not distinctly marked off from the
+remaining ventral surface. It begins on the right side and extends
+entirely around the frontal margin and down the left side below the
+middle of the body, where it turns suddenly to the right, entering
+the slightly insunk peristome. The mouth leads into a short,
+indistinct Å“sophagus. One contractile vacuole is situated in the
+dorsal swelling at the posterior end of the animal. Macronucleus
+double, one in each side of the dorsal swelling. Movement is slow and
+creeping, with a peculiar method of contracting the more hyaline
+edge, which may turn upward or around a foreign object.</p>
+
+<p>Fresh (?) and salt water.</p>
+
+
+<a name="Peritromus emmae"></a>
+<br>
+<p class="noindent"><b>Peritromus emmæ</b> Stein.  Fig. 49.</p>
+
+<p>With the characters of the genus.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_49.jpg">
+<img src="images/fig_49t.jpg" width="280" border=0
+alt="Peritromus emmae,
+ventral and lateral aspects."></a>
+</td><td align="center">
+<b>Fig. 49.&mdash;<br>
+<i>Peritromus emmæ</i>,<br>
+ventral and lateral aspects.</b>
+<br>
+<br>
+<a href="images/fig_49.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<center>
+<br><a name="Oxytrichidae"></a><a name="Oxytrichidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to the marine genera of Oxytrichidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3">
+      <i>Diagnostic characters:</i> The peristome is not always
+      marked off from the frontal area. In the most primitive
+      forms the cilia on the ventral surface are similar to
+      those of the preceding family
+      (<a href="#Peritromidae1"><i>Peritromidæ</i></a>). Usually
+      some of the anterior and some of the posterior cilia are
+      fused into cirri, distinguished as the frontal and anal
+      cirri, respectively. In the majority of forms all of the
+      cilia are thus differentiated; strong marginal cirri are
+      formed in perfect rows, and ventral cirri in imperfect
+      rows. In addition to the adoral zone there is an
+      undulating membrane on the right side of the peristome,
+      and in some cases a row of cilia between the membrane and
+      the adoral zone. These are the par-oral cilia and they
+      form the par-oral zone.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      1.
+    </td>
+    <td width="60%" valign="top">
+      The posterior end is pointed or tail-like
+    </td>
+    <td valign="top">
+      2
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      The posterior end is rounded; not tail-like
+    </td>
+    <td valign="top">
+      5
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      2.
+    </td>
+    <td width="60%" valign="top">
+      The front end is pointed
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      The front end is rounded
+    </td>
+    <td valign="top">
+      4
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      3.
+    </td>
+    <td width="60%" valign="top">
+      Frontal and anal cirri absent; often tube-forming
+    </td>
+    <td valign="top">
+      Genus <i>Stichotricha</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      Eight frontal and 3 caudal cirri; not tubiculous
+    </td>
+    <td valign="top">
+      Genus <i>Gonostomum</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      4.
+    </td>
+    <td width="60%" valign="top">
+      Anal cirri present; with or without short lateral bristles
+    </td>
+    <td valign="top">
+      Genus *<a href="#Epiclintes"><i>Epiclintes</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      Anal cirri absent; no bristles
+    </td>
+    <td valign="top">
+      Genus <i>Uroleptus</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      5.
+    </td>
+    <td width="60%" valign="top">
+      With frontal cirri
+    </td>
+    <td valign="top">
+      6
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      No frontal cirri; 2 to 3 rows of ventral cirri;
+      anal cirri small
+    </td>
+    <td valign="top">
+      Genus <i>Holosticha</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      6.
+    </td>
+    <td width="60%" valign="top">
+      Right margin of peristome straight as far as the anterior
+      end; 5 rows ventral cirri; 5 anal cirri
+    </td>
+    <td valign="top">
+      Genus <i>Oxytricha</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      Right margin of peristome curved
+    </td>
+    <td valign="top">
+      7
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      7.
+    </td>
+    <td width="60%" valign="top">
+      Five rows or less of ventral cirri
+    </td>
+    <td valign="top">
+      8
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      More than 5 rows of ventral cirri
+    </td>
+    <td valign="top">
+      Genus <i>Urostyla</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      8.
+    </td>
+    <td width="60%" valign="top">
+      Membranelles normal; 5-10 anal cirri; no caudal cirri
+    </td>
+    <td valign="top">
+      Genus *<a href="#Amphisia"><i>Amphisia</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      Membranelles normal; 5 to 10 anal cirri; 3 caudal cirri
+    </td>
+    <td valign="top">
+      Genus <i>Stylonychia</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      Membranelles very large and powerful; adoral zone not
+      continued to mouth; 5 anal cirri
+    </td>
+    <td valign="top">
+      Genus <i>Actinotricha</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Epiclintes"></a>
+<br>
+<h3>Genus EPICLINTES Stein '62.</h3>
+
+<div class="center"><span class="syn">(Stein '62, '64, '67;
+Mereschowsky '79; Gruber '87; B&uuml;tschli '88.)</span></div>
+
+<p>Very active, contractile, colorless forms of rather small size. In
+the fully expanded condition the body is oval and long, with its
+greatest width in the center or at the front half of the body. The
+posterior end is always drawn out into a relatively long tail, which
+is extremely elastic. The peristome is short and stretches around the
+front end of the animal. In the frontal region are from one to three
+rows of cirri. The ventral surface is covered with longitudinal rows
+of cilia, the number of rows being in dispute (6 to 7 according to
+Stein; 9 according to Mereschowsky and Rees) Some of these cilia
+project from the lateral edges and from the posterior end, where they
+are slightly elongated. The anus is dorsal and placed at the
+beginning of the posterior process. Macronucleus probably double.
+Movement is rapid and restless, the tail process contracting to jerk
+the body backward. Salt water.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_50.jpg">
+<img src="images/fig_50t.jpg" width="250" border=0
+alt="Epiclintes radiosa"></a><br>
+<b>Fig. 50.&mdash;<br>
+<i>Epiclintes radiosa</i>.</b>
+<br>
+<a href="images/fig_50.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<a name="Epiclintes_radiosa"></a>
+<br>
+<p class="noindent"><b>Epiclintes radiosa</b> Quenn.  Fig. 50.</p>
+
+<p class="syn">Synonym: <i>Metra radiosa</i> Quenn.</p>
+
+<p>The body is elongate, slightly narrowed anteriorly, and drawn out
+posteriorly into a long, retractile, tail-like portion. Five large
+cirri extend outward from the anterior extremity. The caudal portion
+may be extended to a distance equal to twice the length of the body
+or contracted to half the length. The peculiar nervousness of this
+form made it extremely difficult to study, and the oral region was
+imperfectly made out. The anterior cirri appear to line the upper
+left border of the peristome, which is marked by a row of large
+cilia. The peristome begins upon the right side of the anterior end
+and passes backward and to the left, narrowing at this point. The
+mouth is very small and difficult to see. It is apt to stay in one
+locality under zooglœa, switching back and forth with great
+vivacity, or hanging on by the posterior cilia while the anterior end
+stretches out in the surrounding medium. Nucleus and contractile
+vacuole were not observed. Length 45&micro;.</p>
+
+
+<br>
+<br><a name="Amphisia"></a>
+<br>
+<h3>Genus AMPHISIA Sterki '78.</h3>
+
+<div class="center"><span class="syn">(Sterki '78; Kent '81;
+B&uuml;tschli '88.)</span></div>
+
+<p>The body is plastic and soft, colorless or slightly tinged with
+yellow or red. In form it is oval or elongate, the posterior end is
+rounded and slightly reduced in diameter, but does not form a
+distinct tail. The anterior end is also rounded and similarly reduced
+in width. There are two rows of marginal cirri (<i>Randcirren</i>), which
+may be placed some distance from the edge, and two or three rows of
+ventral cirri between them. There are from 3 to 5 frontal cirri of
+larger size than those of the ventral rows, and from 5 to 10 anal
+cirri. (The genus <i>Holosticha</i> is similar in all respects save the
+presence of frontal cirri.) The macronucleus is double; the
+contractile vacuole is central and on the left side. The peristome is
+long and rather narrow and carries an undulating membrane on its
+right margin. Fresh and salt water.</p>
+
+
+<a name="Amphisia_kessleri"></a>
+<br>
+<p class="noindent"><b>Amphisia kessleri</b> Wrzes. '77.  Fig. 51.</p>
+
+<p class="syn">Synonyms: <i>Trichoda gibba</i> M&uuml;ller; <i>Oxytricha gibba</i> Stein '59; <i>O.
+velox?</i> Quen. '69; <i>O. kessleri</i> Wrzes. '77.</p>
+
+<p>Body elongate, slightly sigmoid and swollen in the center, about
+3-1/2 times as long as broad; the rounded anterior end is turned to
+the left, the similarly rounded posterior end to the right; both ends
+taper slightly. The peristome is long and narrow, with a distinct
+adoral zone which appears broken in its course. To the right of this
+adoral zone is a single line of preoral cilia. On the right border of
+the peristome is an undulating membrane. The three frontal cirri form
+a triangle and the five smaller anal cirri form a continuous line
+with the broken row of ventral cirri. There are two and one-half rows
+of ventral cirri and the marginal cirri are drawn in until they are
+ventral in position.</p>
+
+<p>Length 135&micro;; greatest width 40&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_51.jpg">
+<img src="images/fig_51t.jpg" width="450" border=0
+alt="Amphisia kessleri"></a>
+<br>
+<b>Fig. 51.&mdash;<i>Amphisia kessleri</i>.</b>
+<br>
+<br>
+<a href="images/fig_51.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p>This variety differs from <i>O. kessleri</i> as described by Wrzesniowski
+in having three frontal cirri instead of four. Another difference is
+in the structure of the nuclei and in their position. These
+differences are too minute to warrant a specific name. <i>O. velox</i> of
+Quennerstedt is probably the same as <i>0. kessleri</i>, but differs in
+having three complete rows of ventral cirri. <i>O. velox</i> has three
+frontal cirri in a line, thus differing from the Woods Hole form.</p>
+
+
+<center>
+<br><a name="Euplotidae1"></a><a name="Euplotidae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to the marine genera of Euplotidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3">
+      <i>Diagnostic characters:</i> Cilia, as well as the
+      frontal, marginal, and ventral cirri, very much reduced;
+      the anal cirri, on the other hand, are always present.
+      The macronucleus is band-form.
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      1.
+    </td>
+    <td width="60%" valign="top">
+      Frontal cirri more than 8
+    </td>
+    <td valign="top">
+      2
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      Frontal cirri less than 8
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      2.
+    </td>
+    <td width="60%" valign="top">
+      Eleven marginal cirri on the left side; 11 frontal cirri
+    </td>
+    <td valign="top">
+      Genus <i>Certesia</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      Four marginal cirri, 2 on each side; 9 to 10 frontal cirri
+    </td>
+    <td valign="top">
+      Genus *<a href="#Euplotes"><i>Euplotes</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      3.
+    </td>
+    <td width="60%" valign="top">
+      Seven frontal, 5 anal, 3 right marginal, and 2 left
+      marginal cirri
+    </td>
+    <td valign="top">
+      Genus *<a href="#Diophrys"><i>Diophrys</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      &nbsp;
+    </td>
+    <td width="60%" valign="top">
+      No frontal, 5 anal, 3 right, and 2 left marginal cirri
+    </td>
+    <td valign="top">
+      Genus *<a href="#Uronychia"><i>Uronychia</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Euplotes"></a><a name="Euplotes1"></a><a name="Euplotes2"></a><a name="Euplotes3"></a>
+<br>
+<h3>Genus EUPLOTES (Ehr. 1831) Stein '59.</h3>
+
+<div class="center"><span class="syn">(Ehrenberg '31, '38;
+Stein '59; Cl. &amp; Lach. '58; Quennerstedt '65, '67, '69;<br>
+B&uuml;tschli '88; Kent '81; Gourret &amp; Roeser '88;
+Möbius '88.)</span></div>
+
+<p>Small to medium-sized forms. Rigid in form, colorless, or green by
+chlorophyl. They are quite flat on the ventral surface but decidedly
+arched dorsally, and the contour is usually oval. The anterior end is
+broadly rounded to truncate; the posterior end is similarly rounded,
+or may be somewhat pointed. The mouth is placed centrally or near the
+left margin, and from it the right edge of the peristome forms a
+curved line to the left, which bends forward, thus making the greater
+part of the left edge the peristomial area. In front the peristome
+bends sharply to the right and extends as far as the right end of the
+adoral zone. Upon the frontal and median ventral surface are 9 to 10
+great cirri (<i>Bauchwimpern</i> of Stein). Posteriorly five great anal
+cirri stretch out beyond the posterior body margin. In addition to
+these there are two smaller marginal cirri upon the left body edge,
+and two similar ones on the hinder part of the body. The dorsal
+surface is rarely smooth, but usually is marked by longitudinal
+ridges, and rows of dorsal bristles have been described. The single
+contractile vacuole lies on the right side in the region of the anal
+cirri, sometimes just above them, sometimes below. The anus is
+posterior and on the right side. The characteristic macronucleus is
+long and band-form, its main portion being usually on the left side
+with an anterior and a posterior arm toward the right. Movement is
+rapid swimming, which, however, is frequently broken by creeping
+periods, during which the animals appear to be examining the foreign
+body on which they creep.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Euplotes_charon"></a>
+<br>
+<p class="noindent"><b>Euplotes charon</b> Ehr.  Fig. 52.</p>
+
+<p class="syn">Synonyms: <i>Trichoda charon</i> M&uuml;ller;
+<i>Plœsconia charon</i>; <i>P.
+affinis</i>, <i>subrotunda</i>, <i>radiosa</i>, <i>longiremis</i>, Dujardin '41.</p>
+
+<p>The body is oval, small, and somewhat variable in length. The
+carapace is strongly marked upon the dorsal side by deep longitudinal
+grooves, 6 to 8 in number; the grooves may be absent, however. The
+adoral zone extends to the posterior third of the body, the mouth and
+Å“sophagus are directed anteriorly. There are 10 ventral cirri, 7 of
+which are on or near the frontal border and 3 near the right edge.
+There are 5 posterior cirri and 4 anal cirri, of much smaller size.
+The cirri may or may not be fimbriated, the latter condition
+indicating the approaching disintegration of the body and is
+abnormal. The macronucleus is long and band-formed or horseshoe
+shape. The contractile vacuole lies on the right side dorsal to the
+posterior cirri.</p>
+
+<p>Fresh and salt water. Length 45&micro;; diameter 25&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_52.jpg">
+<img src="images/fig_52t.jpg" width="400" border=0
+alt="Euplotes charon,
+dorsal and ventral aspects"></a>
+</td><td align="center">
+<b>Fig. 52.&mdash;<br>
+<i>Euplotes charon</i>,<br>
+dorsal and<br>
+ventral aspects.</b>
+<br>
+<br>
+<a href="images/fig_52.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Euplotes_harpa"></a>
+<br>
+<p class="noindent"><b>Euplotes harpa</b> Stein.  Fig. 53.</p>
+
+
+<table class="imagetable" align="right" ><tr><td align="center">
+<a href="images/fig_53.jpg">
+<img src="images/fig_53t.jpg" width="230" border=0
+alt="Euplotes harpa"></a>
+</td><td align="center">
+<b>Fig. 53.&mdash;<br>
+<i>Euplotes harpa</i>.</b>
+<br>
+<br>
+<a href="images/fig_53.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr></table>
+
+
+<p>The body is elongate, oval, somewhat widened anteriorly, and has
+rounded ends. The frontal margin is three-toothed. Ten ventral cirri.
+Dorsal surface provided with 8 longitudinal markings. The peristome
+is long and broad, with considerable variation. The adoral zone
+consists of powerful membranelles arranged in a continuous curve from
+the mouth to the extreme right frontal margin. Seven of the 10
+ventral cirri are situated at the anterior extremity; the remainder
+are arranged in a triangle on the right edge. The anal cirri, 5 in
+number, are long and stiff; the marginal cirri smaller and finer. The
+nucleus and contractile vacuole are similar to those of the preceding
+species.</p>
+
+<p>Length 95&micro;; width 54&micro;.</p>
+
+
+<br>
+<br><a name="Diophrys"></a>
+<br>
+<h3>Genus DIOPHRYS Dujardin '41.</h3>
+
+<div class="center"><span class="syn">(B&uuml;tschli '88.)</span></div>
+
+<p>Medium size, colorless to yellow, rigid in form. The body contour is
+oval, the anterior end being rounded or slightly reduced, the
+posterior end usually cut in on the right side. The peristome is
+broad but less extensive than in
+<a href="#Euplotes1"><i>Euplotes</i></a>, and may extend beyond
+the middle of the body. Its right edge is convex toward the right
+side, extends forward and does not turn again to the right. The
+anterior ventral surface has 7 to 8 scattered cirri and just behind
+the mouth is a transverse row of large anal cirri. In the sharp
+in-cut of the posterior end are three great angular cirri. Two
+lateral cirri are placed on the left of the median line between the
+mouth and the anal cirri, and usually in a slight hollow. The
+contractile vacuole is on the right side in the vicinity of the anal
+cirri. The macronucleus is in two parts, each band-form, one
+anterior, the other posterior in position. Movement is rapid and
+steady. Salt water.</p>
+
+
+<a name="Diophrys_appendiculatus"></a>
+<br>
+<p class="noindent"><b>Diophrys (Styloplotes) appendiculatus</b>
+Stein '59.  Fig. 54.</p>
+
+<p class="syn">Synonyms: <i>Styloplotes appendiculatus</i> Stein '59; Kent '81;
+Quennerstedt '67, etc.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_54.jpg">
+<img src="images/fig_54t.jpg" width="230" border=0
+alt="Diophrys appendiculatus"></a>
+<br>
+<b>Fig. 54.&mdash;<br>
+<i>Diophrys appendiculatus</i>.</b>
+<br>
+<br>
+<a href="images/fig_54.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The general form resembles <a href="#Euplotes2"><i>Euplotes</i></a>.
+Its outline is oval and
+regular except at the posterior end on the right side, where there is
+a considerable indentation. The frontal margin is characterized by a
+row of powerful membranelles, which become smaller at the peristome
+and at the mouth they are of characteristically small size. The
+ventral cirri are 7 in number. Five of them are in one row from the
+anterior end down the right side nearly to the anal cirri; 1 is on
+the frontal border between the first two; 1 lies just anterior to the
+second anal cirrus from the right side. The 5 anal cirri are large
+and powerful and extend some distance beyond the posterior end of the
+body. In all specimens observed these cirri curve to the left. Dorsal
+to the anal cirri and placed deep into the dorsal pit are 3 large,
+sharply curved cirri, which in most cases are fimbriated, but when
+the specimens are normal these are pointed and curve abruptly to the
+right. Two smaller cirri lie to the left of the group of anal cirri.
+The peristome is well-marked by the adoral zone, and upon its right
+border there is a row of cilia, and a similar row of cilia runs along
+the base of the oral membranelle. The macronucleus is double and
+consists of two elongate cylindrical masses lying parallel with one
+another. One of these is in the anterior region; the other is
+posterior. The contractile vacuole lies dorsal to the anal cirri and
+anterior to the three dorsal cirri. The movement and general
+activities resemble those of <i>Euplotes</i>.</p>
+
+<p>Length 50&micro;; diameter 25&micro;.</p>
+
+
+<br>
+<br><a name="Uronychia"></a>
+<br>
+<h3>Genus URONYCHIA Stein '52.</h3>
+
+<div class="center"><span class="syn">(Stein '59, '67;
+Quennerstedt '67; Kent '81; B&uuml;tschli '88.)</span></div>
+
+<p>Medium-sized colorless ciliates of usually constant body form. The
+body is somewhat short and oval in outline. The anterior end is
+broadly truncate, the posterior end rounded or slightly pointed. The
+ventral and dorsal surfaces are considerably arched and the latter
+usually has a number of rows of longitudinal stripes. The open
+peristome is broad and reaches back to the middle of the ventral
+surface and beyond. According to Stein, the two edges can approach
+each other, thus opening and closing the peristomial area. Its right
+edge forms a greater angle with the front edge than in the genus
+<a href="#Euplotes3"><i>Euplotes</i></a>,
+and the left edge forms a greater angle with the front
+edge than in that genus. The left edge also appears to cover over the
+adoral zone slightly. There are no ventral cirri in front, but on the
+posterior ventral surface are 7 great springing cirri. Five of these
+are inserted on the right aide in a deep in-sinking, and the other 2
+in a similar depression on the left ventral surface. Above the 5
+right-side cirri, <i>i.e.</i>, dorsal to them, but in the same depression,
+are 3 angular cirri. A few edge cirri are found to the left of them
+and another to the right of the 5 cirri. The contractile vacuole is
+on the left side between the main groups of cirri. The macronucleus
+is band-form or spherical, and is situated in the middle region of
+the body. Movement consists in forward swimming with sudden springs.</p>
+
+<p>Salt water.</p>
+
+
+<a name="Uronychia_setigera"></a>
+<br>
+<p class="noindent"><b>Uronychia setigera</b>, n. sp.  Fig. 55.</p>
+
+<p>This species is very common in the Woods Hole waters. It is small,
+colorless, and very active. The most characteristic feature is the
+posterior end with its relatively enormous cirri, which are
+apparently large enough for an animal four times its size. The form
+is ovoid, widened posteriorly.</p>
+
+
+<table class="imagetable" align="right" ><tr><td>
+<center>
+<a href="images/fig_55.jpg">
+<img src="images/fig_55t.jpg" width="240" border=0
+alt="Uronychia setigera"></a>
+<br>
+<b>Fig. 55.&mdash;<br>
+<i>Uronychia setigera</i>.</b>
+<br>
+<br>
+<a href="images/fig_55.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The ventral surface is flat and has two excavations in the posterior
+end. The right hollow is larger and contains 5 great cirri of unequal
+size, the extreme right one being the largest. The left hollow
+contains 2 cirri, also of dissimilar size. Dorsal to the 5 right
+cirri are 3 sickle-formed cirri, which are usually fimbriated. These
+are pointed and curve regularly to the left. The peristome is wide
+and open, and a small pocket-like hollow on its left border indicates
+the region of the mouth. The adoral zone runs into this pocket and
+the mouth is located in its lower right-hand corner. In <i>U.
+transfuga</i> the right border is generally described as having a
+membrane of extreme delicacy. I was unable to see such a membrane in
+this form, but in its place there are 2 flagella-like cirri extending
+from the margin of the mouth-opening into the peristome, and these
+vibrate slowly. I do not believe these could be the moving edge of an
+undulating membrane, for they are quite distinct. The macronucleus is
+spherical instead of band-form, and a single micronucleus is closely
+attached. This is unlike the European species <i>U. transfuga</i>, in
+which the nucleus is elongate. The contractile vacuole lies between
+the two sets of posterior cirri. There are no marginal folds like
+those of the European species.</p>
+
+<p>Length 40&micro;; width 25&micro;. Common.</p>
+
+
+<br>
+<br><a name="Aspidisca"></a>
+<br>
+<h3>Genus ASPIDISCA Ehr. 1830.</h3>
+
+<div class="center"><span class="syn">(Perty '52; Cl &amp; Lach. '58;
+Stein '59; Quennerstedt '65, '67, '69;<br>
+Mereschowsky '79; Kent '81; B&uuml;tschli '88.)</span></div>
+
+<p>Small, colorless, and rigid forms, with nearly circular to oval
+contour. The left side is usually straight, or at least but slightly
+convex. The right side is much more convex, and the right margin is
+considerably thickened. The ventral side is flat, the dorsal surface
+convex, with from one to several longitudinal ridges which run more
+or less parallel with the right edge. The peristome is limited to the
+left edge, where it forms a small depression which may or may not
+reach the anterior border, but which in no case runs around the
+anterior margin. The left peristome margin in some cases grows over
+the peristome depression toward the right, thus making a sort of
+cover for the peristome. In the posterior region is a deep
+depression, from which 5 to 12 cirri take their origin. Seven or 8
+cirri are placed in the anterior half of the ventral surface and are
+arranged more or less in rows. The anus is on the right side in the
+region of the anal cirri (Stein). The contractile vacuole is
+generally on the right side and similarly located. The macronucleus
+is a horseshoe-shaped body. Movement rapid, somewhat in circles, and
+rather uniform.</p>
+
+<p>Fresh and salt water.</p>
+
+
+<a name="Aspidisca_hexeris"></a><a name="A_hexeris"></a>
+<br>
+<p class="noindent"><b>Aspidisca hexeris</b> Quennerstedt '67.
+Fig. 56.</p>
+
+<p>The carapace is elliptical, about 1-1/2 times as long as broad,
+rounded at the extremities. The left border of the carapace bears a
+spur-like projection. The ventral cirri are short and thick, and are
+very characteristic of the species. When moving slowly they look much
+like nicely-pointed paint brushes, but when the animal is compressed
+they quickly become fibrillated, and then look like extremely old and
+worn brushes. These cirri are placed in depressions in the ventral
+surface and each one appears to come from a specific shoulder. At the
+posterior end an oblique hollow bears 6 unequal cirri placed side by
+side. The extreme right cirrus is the largest, and they become
+progressively smaller to the opposite end. Dorsal to these lies the
+contractile vacuole. The peristome is in the posterior half of the
+body and an undulating membrane extends from it into the Å“sophagus.
+The dorsal surface is longitudinally striated by 5 or 6 lines, which
+are usually curved. The nucleus is horseshoe-shaped and lies in the
+posterior half of the body. Length 68&micro;; diameter 48&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_56.jpg">
+<img src="images/fig_56t.jpg" width="400" border=0
+alt="Aspidisca hexeris"></a>
+</td><td align="center">
+<b>Fig. 56.&mdash;<br>
+<i>Aspidisca hexeris</i>.</b>
+<br>
+<br>
+<a href="images/fig_56.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+<p>This form was incorrectly mentioned as <i>Mesodinium</i> sp. by Peck '95:</p>
+
+<p>In the figure given by Quennerstedt there are only 7 ventral cirri.
+In the Woods Hole form there are 8, 7 of which are anterior, 6 of
+them about one central one. The eighth cirrus is by itself, near the
+base of the largest posterior cirrus. These cirri, in spite of their
+size, are easily overlooked and more easily confused, but by using
+methylene blue they can be seen and counted.</p>
+
+
+<a name="Aspidisca_polystyla"></a>
+<br>
+<p class="noindent"><b>Aspidisca polystyla</b> Stein.  Fig. 57.</p>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_57.jpg">
+<img src="images/fig_57t.jpg" width="150" border=0
+alt="Aspidisca polystyla"></a>
+<br>
+<b>Fig. 57.&mdash;<br>
+<i>Aspidisca polystyla</i>.</b>
+<br>
+<br>
+<a href="images/fig_57.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>This species is similar to
+<a href="#A_hexeris"><i>A. hexeris</i></a>, but is smaller, very
+transparent, and without the spur-like process on the left edge of
+the carapace. The chief difference, however, lies in the number of
+anal cirri. These are 10 in number and they are arranged obliquely as
+in the preceding species, with the largest one on the right and the
+smallest on the left. The ventral cirri are 8 in number, and are
+arranged in two rows, one of which, the right, has 4 cirri closely
+arranged, the other having 3 cirri close together and one at some
+distance, near the largest anal cirrus. The peristome, contractile
+vacuole, and nucleus are similar to the preceding. Length 36&micro;; width
+22&micro;.</p>
+
+<p>Stein assigns only 7 ventral cirri to this species, but he also
+describes 2 very fine bristle like cilia (p. 125) and pictures them
+in figs. 18, 19, 20, and 21 of his Taf. III in the same relative
+position as my eighth cirrus. I am positive that cilia do not occur
+on the ventral face of this form, and that the characteristic cirri
+are the sole locomotor organs.</p>
+
+
+<center>
+<br><a name="Peritrichida"></a><a name="Peritrichida1"></a><a name="Lichnophoridae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to families of Peritrichida.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      a.
+    </td>
+    <td width="60%" valign="top">
+      Peristome drawn out into funnel-like process; parasitic
+    </td>
+    <td valign="top">
+      Family <i>Spirochonidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      b.
+    </td>
+    <td width="60%" valign="top">
+      Adoral zone and circlet of cilia at opposite end. Adoral
+      zone left-wound. Parasitic.
+    </td>
+    <td valign="top">
+      Family <i>Lichnophoridæ</i><br>
+      (one genus, *<a href="#Lichnophora"><i>Lichnophora</i>)</a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      c.
+    </td>
+    <td width="60%" valign="top">
+      Adoral zone a left-wound spiral. Attached or unattached
+      forms.
+    </td>
+    <td valign="top">
+      Family <a href="#Vorticellidae1"><i>Vorticellidæ</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Lichnophora"></a><a name="Lichnophora1"></a>
+<br>
+<h3>Genus LICHNOPHORA Clapar&egrave;de '67.</h3>
+
+<div class="center"><span class="syn">(Gruber '84; Fabre-Domergue '88;
+B&uuml;tschli '88; Wallengren '94;
+Stevens 1901.)</span></div>
+
+<p>Small or medium-sized colorless animals, extremely elastic and
+flexible. The anterior part, bearing the adoral zone, is round or
+oval in ventral view, and has a flat ventral and a highly arched
+dorsal surface. The posterior end of the animal is reduced to a
+stalk-like structure which is broadened at the extremity to form a
+sucking disk. The surface of this disk and the surface of the
+peristome may be brought into the same plane by the characteristic
+bending of the stalk portion. A ciliated girdle is placed at the edge
+of the sucking disk. A well-developed adoral zone incloses the
+peristome; it begins at the mouth on the left side and includes
+nearly all of the peristome in its left-wound spiral, the extremity
+approaching closely the end near the mouth. The macronucleus is a
+long-beaded structure, or it may be in several parts connected by
+strands (Gruber). The contractile vacuole is on the left side in the
+region of the mouth. Salt water.</p>
+
+
+<a name="Lichnophora_macfarlandi"></a>
+<br>
+<p class="noindent"><b>Lichnophora macfarlandi</b> Stevens.  Fig. 58.</p>
+
+<p>The body is elongate; oral disk variable in form, attachment disk
+clearly defined and constant. The stalk is very contractile and
+elastic, constantly changing in shape. When detached from the host
+the animal moves with a very irregular and indefinite motion. When
+attached it moves freely over the surface on its pedal disk. The
+latter is bordered by four membranes composed of cilia. A distinct
+axial fiber extends from the pedal disc to the peristome and gives
+off a number of branches. This fiber is analogous to the myonemes in
+<i>Vorticella</i>. An indistinct longitudinal furrow can be made out
+occasionally. The nucleus is in 5 or 6 separate pieces, of which 1 is
+found in the pedal disk and 1 or 2 in the neck.</p>
+
+<p>On the egg capsules of <i>Crepidula plana</i>; also reported upon annelids
+at Woods Hole.</p>
+
+<p>Length 60&micro; from disk to extremity of the peristomial disk.</p>
+
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_58.jpg">
+<img src="images/fig_58t.jpg" width="375" border=0
+alt="Lichnophora macfarlandi"></a>
+</td><td align="center">
+<b>Fig. 58.&mdash;<br>
+<i>Lichnophora macfarlandi</i>.</b>
+<br>
+<br>
+<a href="images/fig_58.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p>This form does not agree in all respects with Stevens's species, but
+the agreement is so close in other respects that I believe it can be
+safely identified as <i>L. macfarlandi</i>. The mode of life is different,
+and the macronucleus is different, there being from 25 to 30
+fragments in Stevens's form and only 5 or 6 in the present one. There
+is, however, the same evidence of chain formation in both of them.
+The length of the oral cilia in  Stevens's form is 18&micro; in fixed and
+30&micro; in living forms. In the Woods Hole form the cilia are not more
+than half that length.</p>
+
+
+<center>
+<br><a name="Vorticellidae"></a><a name="Vorticellidae1"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="4" align="center">
+      <b><i>Key to the marine genera of Vorticellidæ.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="left">
+      <i>Diagnostic characters:</i> Attached or unattached forma of
+      peritrichous ciliates in which the adoral zone seen from above
+      forms a right-wound spiral. A secondary circlet of cilia around
+      the posterior end may be present either permanently or
+      periodically.
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      1.
+    </td>
+    <td colspan="2" valign="top">
+      Posterior ciliated girdle permanent around an attaching disk
+    </td>
+    <td valign="top">
+      3
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      2.
+    </td>
+    <td colspan="2" valign="top">
+      Posterior ciliated girdle, temporary during motile stage
+    </td>
+    <td width="55%" valign="top">
+      4
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      3.
+    </td>
+    <td colspan="3" valign="top">
+      Body cylindrical:
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      (a)
+    </td>
+    <td width="55%" valign="top">
+      With ring of stiff bristles above the ciliated girdle
+    </td>
+    <td valign="top">
+      Genus <i>Cyclochæta</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      (b)
+    </td>
+    <td width="55%" valign="top">
+      Without accessory ring of bristles; with velum
+    </td>
+    <td valign="top">
+      Genus <i>Trichodina</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="5%" valign="top">
+      &nbsp;
+    </td>
+    <td width="55%" valign="top">
+      Body conical; general surface ciliated
+    </td>
+    <td valign="top">
+      Genus <i>Trichodinopsis</i>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      4.
+    </td>
+    <td colspan="2" valign="top">
+      No test and no stalk
+    </td>
+    <td valign="top">
+      Genus <i>Scyphidia</i>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      5.
+    </td>
+    <td colspan="2" valign="top">
+      No test; with stalk containing contractile thread
+    </td>
+    <td valign="top">
+      8
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      6.
+    </td>
+    <td colspan="2" valign="top">
+      No test; with stalk but without contractile thread
+    </td>
+    <td valign="top">
+      Genus <i>Epistylis</i>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      7.
+    </td>
+    <td colspan="2" valign="top">
+      With a test; with or without a stalk
+    </td>
+    <td valign="top">
+      Genus *<a href="#Cothurnia"><i>Cothurnia</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      8.
+    </td>
+    <td colspan="2" valign="top">
+      Individuals solitary
+    </td>
+    <td valign="top">
+      Genus *<a href="#Vorticella"><i>Vorticella</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      &nbsp;
+    </td>
+    <td colspan="2" valign="top">
+      Individuals colonial; entire colony contractile
+    </td>
+    <td valign="top">
+      Genus *<a href="#Zoothamnium"><i>Zoothamnium</i></a>
+    </td>
+  </tr>
+  <tr>
+    <td valign="top">
+      &nbsp;
+    </td>
+    <td colspan="2" valign="top">
+      Individuals colonial; parts only of the colony contractile
+    </td>
+    <td valign="top">
+      Genus <i>Carchesium</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="4" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Vorticella"></a><a name="Vorticella1"></a><a name="Vorticella2"></a>
+<br>
+<h3>Genus VORTICELLA (Linnæus 1767) Ehr. '38</h3>
+
+<div class="center"><span class="syn">(Bell Animalcule Leeuwenhoek 1675;
+Ehrenberg '38; Dujardin '41;<br>
+Stein '51; Cl. &amp; Lach. '58; Greeff '70; B&uuml;tschli '88;
+Kent '81; Stokes '88; etc.)</span></div>
+
+<p>Medium-sized ciliates of general bell-like form. They may be
+colorless, or yellow and green through the presence of Zoochlorella.
+When not contracted, the peristome end is widespread, rarely
+narrowed. The adoral zone and peristome agree with the details given
+in the family characteristics. The chief character is the attachment
+of the posterior end by means of a single, longer or shorter, stalk,
+which contains a highly contractile thread easily distinguished in
+the living animal. Another character is the absence of colony
+formation. Contractile vacuole, single or double, usually connected
+with a sac-like reservoir. The macronucleus is invariably long and
+band-formed, with attached micronucleus. Fresh and salt water.</p>
+
+<p>So many species of <i>Vorticella</i> have been described that the task of
+collecting data and of arranging the synonyms is extremely irksome
+and difficult. Stokes enumerates 66 species, inhabiting fresh and
+salt water, and several other new species have been added since his
+work. I am impressed with the fact that new species have been created
+without proper regard for the manifold variations which nearly all of
+the <i>Ciliata</i> show, and I believe the 66 species might be safely
+reduced to 12 or 15.</p>
+
+
+<a name="Vorticella_patellina"></a>
+<br>
+<p class="noindent"><b>Vorticella patellina</b> M&uuml;ller.  Fig. 59.</p>
+
+<p>Body campanulate, widest at anterior border, from which it tapers
+directly to the pedicle. The diameter of the peristome is a little
+larger than the length of the body. The ciliary disk is but little
+elevated. The cuticle is not striated and the body plasm is quite
+transparent. Length 52&micro;.</p>
+
+
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_59.jpg">
+<img src="images/fig_59t.jpg" width="270" border=0
+alt="Vorticella patellina"></a>
+</td><td align="center">
+<b>Fig. 59.&mdash;<br>
+<i>Vorticella patellina</i>.</b>
+<br>
+<br>
+<a href="images/fig_59.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr></table>
+
+
+<a name="Vorticella_marina"></a>
+<br>
+<p class="noindent"><b>Vorticella marina</b> Greeff.  Fig. 60.</p>
+
+<p>The body is conical but variable, and may he short or elongate, so
+that relative length and breadth offer no chance of identification.
+In general the body is campanulate. The distinguishing feature is the
+transverse annulation of the bell.</p>
+
+<p>Small, but common, and grows in small social groups. Length 35&micro;.</p>
+
+
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_60.jpg">
+<img src="images/fig_60t.jpg" width="200" border=0
+alt="Vorticella marina"></a>
+</td><td align="center">
+<b>Fig. 60.&mdash;<br>
+<i>Vorticella marina</i>.</b>
+<br>
+<br>
+<a href="images/fig_60.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr></table>
+
+
+<br>
+<br><a name="Zoothamnium"></a>
+<br>
+<h3>Genus ZOOTHAMNIUM (Bory de St. Vincent 1824) Stein '38, '54.</h3>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_61.jpg">
+<img src="images/fig_61t.jpg" width="180" border=0
+alt="Zoothamnium elegans"></a>
+<br>
+<b>Fig. 61.&mdash;<br>
+<i>Zoothamnium elegans</i>.</b>
+<br>
+<a href="images/fig_61.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>Colorless and highly contractile forms growing in small or large
+colonies. The form and structure of the individuals is not different
+from <a href="#Vorticella2"><i>Vorticella</i></a>. The colonies
+are usually richly branched upon the
+dichotomous plan and the entire colony is contractile. The main
+character is that with each division of the individual the stalk also
+divides, each daughter cell getting one-half of the parent stem. The
+stems therefore remain in communication, so that a simultaneous
+contraction results, and the colony as a whole is withdrawn. In some
+species so-called macrogonidia, or larger sexual individuals, are
+developed alongside the usual ones. Fresh and salt water.</p>
+
+
+<a name="Zoothamnium_elegans"></a>
+<br>
+<p class="noindent"><b>Zoothamnium elegans</b> D'Udekem '64?  Fig. 61.</p>
+
+<p>The bodies are variable&mdash;peristomial border widely dilated, tapering
+and attenuate posteriorly. The pedicle is slender, smooth, and
+transparent, and branches sparsely at its distal extremity. There are
+but few zooids (3 to 4). The ciliary disk projects conspicuously
+beyond the peristomial border. The pharyngeal cleft is very distinct
+and extends beyond center of body. Length of body 80&micro;.</p>
+
+
+<br>
+<br><a name="Cothurnia"></a>
+<br>
+<h3>Genus COTHURNIA (Ehr. '31) Clap. &amp; Lach. '58.</h3>
+
+<p>Colorless forms of medium size-in some cases they may be green by
+Zoochlorella. The general structure is similar to that of
+<a href="#Vorticella1"><i>Vorticella</i></a>,
+but the individuals are elongate and occupy houses. The
+macronucleus is invariably long and band-form. The distinguishing
+character is the colorless or brownish lorica of quite variable form
+but always attached. These houses may be finger-formed, with widened
+center, or widened mouth, or constricted mouth, and the like.
+Ring-formed swellings are frequently developed. Sometimes the mouth
+becomes twisted and the lorica is therefore bilateral. The houses are
+attached either directly to some foreign object or by means of a
+short stalk. The animals are similarly fastened to the lorica,
+sometimes directly, sometimes by means of a short stalk. When they
+contract they draw back to the bottom of the lorica; when expanded
+they usually stretch out of the mouth opening. In some forms there is
+an operculum, by means of which the opening of the shell can be
+closed when the animal is retracted. Fresh and salt water.</p>
+
+<p>The number of species of <i>Cothurnia</i> has become so great that the
+difficulty in placing forms is almost sufficient to discourage the
+systematist; as B&uuml;tschli well remarks, the variations in the theca
+have been made the basis of new species so many times that the genus
+is almost as confused as <i>Difflugia</i> among the rhizopods or
+<i>Campanularia</i> among the hydroids. The length of cup, of stalk, the
+presence of annulations on stalk or cup, etc., have given rise to
+many specific names, the majority of which I believe can be
+discarded. According to such differentials the same branch of an alga
+holding a hundred specimens of
+<a href="#Cothurnia_crystallina1"><i>Cothurnia crystallina</i></a>
+yield 10 or 12
+species, whereas they are merely growth stages of one and the same
+form.</p>
+
+
+<a name="Cothurnia_crystallina"></a><a name="Cothurnia_crystallina1"></a>
+<br>
+<p class="noindent"><b>Cothurnia crystallina</b> Ehr.  Fig. 62.</p>
+
+<p class="syn">Synonyms: <i>Vaginicolla crystallina</i>
+Ehr., Perty, Eichwald; <i>V.
+grandis</i> Perty; <i>V. pedunculata</i> Eichwald; <i>Cothurnia
+crystallina</i> Clapar&egrave;de &amp; Lachmann, D'Udek.;
+<i>C. gigantea</i> D'Udek; <i>C. maritima</i>,
+<i>C. crystallina</i> Cohn; <i>C. grandis</i> Meresch.</p>
+
+<p>The form of the cup shows the greatest differences; sometimes it is
+cylindrical, sometimes elongate thimble-shape, sometimes pouch-shape,
+corrugated or smooth on the sides, and wavy or smooth on border.
+Frequently the basal part becomes stalk-like, but this is very short.
+When present, the stalk may or may not have a knob-like swelling. The
+animal within the cup may or may not be borne on a stalk, and this
+stalk may or may not be knobbed. The cups are colorless or brown. The
+animal is very contractile and may stretch half its length out of the
+cup or retract well into it. There is no operculum. The length of the
+cup varies from 70&micro; to 200&micro; (<i>C. gigantea</i>; <i>Vag. grandis</i>, etc.).
+From Entz.</p>
+
+<p>There is nothing to add to Entz's characterization of this species,
+which is found both in fresh and salt water. The variability of the
+cup and stalk is quite noticeable in the Woods Hole forms.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td align="center">
+<a href="images/fig_62.jpg">
+<img src="images/fig_62t.jpg" width="500" border=0
+alt="Cothurnia crystallina"></a><br>
+<b>Fig. 62.&mdash;<i>Cothurnia crystallina</i>.</b>
+<br>
+<br>
+<a href="images/fig_62.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Cothurnia_imberbis"></a>
+<br>
+<p class="noindent"><b>Cothurnia imberbis</b> Ehrenberg,
+var. curvula Entz.  Fig. 63.</p>
+
+<p class="syn">Synonyms: <i>C. imberbis</i> Kent et al.;
+<i>C. curvula</i> Entz; <i>C. socialis</i> Gruber?</p>
+
+<p>The lorica is swollen posteriorly, narrowest at the oral margin, bent
+on its axis and is supported on a short stalk. It is perfectly smooth
+and without annulations. The animal itself has no definite stalk.
+When fully expanded the animal emerges but slightly from the margin
+of the cup. Fresh and salt water. On red algæ. Dimensions of Woods
+Hole form: Cup 50 to 55&micro; long; greatest diameter 22&micro;; length of stalk
+4 to 5&micro;.</p>
+
+
+<center>
+<table class="imagetable"><tr><td align="center">
+<a href="images/fig_63.jpg">
+<img src="images/fig_63t.jpg" width="190" border=0
+alt="Cothurnia imberbis"></a>
+</td><td align="center">
+<b>Fig. 63.&mdash;<i>Cothurnia imberbis</i>.</b>
+<br>
+<br>
+<a href="images/fig_63.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<a name="Cothurnia_nodosa"></a>
+<br>
+<p class="noindent"><b>Cothurnia nodosa</b> Clapar&egrave;de &amp; Lachmann.  Fig. 64.</p>
+
+
+<center>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td width="10%" valign="top" align="right">
+      A.
+    </td>
+    <td valign="top">
+      Smooth cup.&mdash;<i>Cothurnia maritima</i> Ehr., Eichwald,
+      Stein, Kent.
+    </td>
+  </tr>
+  <tr>
+    <td width="10%" valign="top" align="right">
+      B.
+    </td>
+    <td valign="top">
+      Cross-ringed cup.&mdash;<i>C. pupa</i> Eichwald, Stein, Cohn;
+      <i>C. nodosa</i> Cl &amp; L.; <i>V. crystallina</i> Entz '78;
+      <i>C. pontica</i> Meresch., Kent; <i>C. cohnii</i> and
+      <i>pupa</i> Kent; <i>C. longipes</i> Kellicott '94.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<p>The cup is elongated, swollen centrally, tapering at oral end and
+conical at base or rounded. Oral opening either circular or
+elliptical. Cross rings may or may not be present, and the cup is
+either smooth or annulate. Length of cup 70&micro; to 80&micro;. The stalk which
+supports the cup is extremely variable in length. The animal is borne
+upon a stalk of variable length within the cup.</p>
+
+<p>Entz states that the many variations which this species exhibits run
+into each other so gradually that he does not believe it wise to
+separate them. The Woods Hole forms which I found on algæ of various
+kinds were nearly of a size, and did not vary much from the one
+figured. Kellicott '94 described a <i>Cothurnia</i> from Woods Hole under
+the name of <i>C. longipes</i>, which I believe is only a long-stemmed
+variety of <i>C. nodosa</i>. My form has the following dimensions: Cup
+75&micro;; cup stalk 38&micro;; animal stalk 14&micro;.</p>
+
+
+<center>
+<table class="imagetable"><tr><td align="center">
+<a href="images/fig_64.jpg">
+<img src="images/fig_64t.jpg" width="150" border=0
+alt="Cothurnia nodosa"></a>
+</td><td align="center">
+<b>Fig. 64.&mdash;<i>Cothurnia nodosa</i>.</b>
+<br>
+<br>
+<a href="images/fig_64.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+<center>
+<br><a name="Suctoria"></a><a name="Suctoria1"></a><a name="Suctoria2"></a><a name="Podophryidae"></a><a name="Acinetidae"></a><a name="Dendrosomidae"></a>
+<br>
+<table class="classtable" cellpadding=5 width="100%">
+  <tr>
+    <td colspan="3" align="center">
+      <b><i>Key to families of Suctoria.</i></b>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      a.
+    </td>
+    <td width="60%" valign="top">
+      Unattached forms; ventral cilia present; one suctorial
+      tentacle
+    </td>
+    <td valign="top">
+      <i>Hypocomidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      b.
+    </td>
+    <td width="60%" valign="top">
+      Attached forms; thecate and athecate tentacles simple,
+      one or two in number
+    </td>
+    <td valign="top">
+      <i>Urnulidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      c.
+    </td>
+    <td width="60%" valign="top">
+      Thecate; posterior end of cup drawn out into stalk; walls
+      perforated for exit of tentacles
+    </td>
+    <td valign="top">
+      <i>Metacinetidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      d.
+    </td>
+    <td width="60%" valign="top">
+      Stalked or unstalked; globular; tentacles of different kinds,
+      some knobbed, others pointed
+    </td>
+    <td valign="top">
+      <i>Podophryidæ</i><br>
+      (2 genera<br>
+      *<a href="#Ephelota"><i>Ephelota</i></a>, *<a href="#Podophrya"><i>Podophrya</i>)</a>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      e.
+    </td>
+    <td width="60%" valign="top">
+      Naked or thecate; stalked or not; tentacles numerous,
+      usually knobbed and all alike
+    </td>
+    <td valign="top">
+      <i>Acinetidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      f.
+    </td>
+    <td width="60%" valign="top">
+      Naked; athecate; tentacles numerous, all alike, knobbed
+      and grouped in tufts. They may be simple or branched.
+    </td>
+    <td valign="top">
+      <i>Dendrosomidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      g.
+    </td>
+    <td width="60%" valign="top">
+      Sessile forms resting on basal surface or on a portion
+      raised like a stalk; tentacles many; short and knobbed;
+      distributed on apical surface or localized on branched
+      arms
+    </td>
+    <td valign="top">
+      <i>Dendrocometidæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td width="5%" valign="top" align="right">
+      h.
+    </td>
+    <td width="60%" valign="top">
+      Stalked or sessile; tentacles long, rarely knobbed,
+      supported on proboscis-like processes
+    </td>
+    <td valign="top">
+      <i>Ophryodendridæ</i>
+    </td>
+  </tr>
+  <tr>
+    <td colspan="3" align="center">
+      * Presence at Woods Hole indicated by asterisk.
+    </td>
+  </tr>
+</table>
+</center>
+
+
+<br>
+<br><a name="Podophrya"></a>
+<br>
+<h3>Genus PODOPHRYA Ehr. '33.</h3>
+
+<div class="center"><span class="syn">(B&uuml;tschli '88; Stein '59;
+Perty '52; Cienkowsky '55;<br>
+Quenn. '69; Hertwig '77; Maupas '81.)</span></div>
+
+
+<table class="imagetable" align="right" width="140"><tr><td>
+<center>
+<a href="images/fig_65.jpg">
+<img src="images/fig_65.jpg" width="100" border=0
+alt="Podophrya gracilis"></a>
+<br>
+<b>Fig. 65.&mdash;<br>
+<i>Podophrya gracilis</i>.</b><br>
+<a href="images/fig_65.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>The body is globular, with tentacles radiating in all directions. The
+tentacles may be very short or very long. The stalk also is either
+short or long, and some species form stalks but rarely (<i>P. libera</i>).
+The macronucleus is centrally placed and globular to ovoid in form.
+The contractile vacuole is usually single. Reproduction takes place
+by division; the distal half developing cilia and becoming a
+swarm-spore. Fresh and salt water.</p>
+
+
+<a name="Podophrya_gracilis"></a>
+<br>
+<p class="noindent"><b>Podophrya gracilis</b>, n. sp.  Fig. 65.</p>
+
+<p>Of all the <i>Podophrya</i> that have been described not one approaches
+this minute form in the relative length of the stalk. The body is
+spherical and is covered with short capitate tentacles. The stalk is
+extremely slender, bent, and without obvious structure. There are one
+or two contractile vacuoles in the distal half of the body. The
+nucleus is small and is situated near the insertion-point of the
+stalk. Reproduction not observed. Diameter of body 8&micro;; length of
+stalk 40&micro;. Only one specimen seen.</p>
+
+
+<br>
+<br><a name="Ephelota"></a>
+<br>
+<h3>Genus EPHELOTA Str. Wright '78.</h3>
+
+<div class="center"><span class="syn">(B&uuml;tschli '88;
+Ishikawa '96; Sand '98.)</span></div>
+
+<p>Small to medium-sized and large forms; colorless to brown. The body
+is globular or oval or wedge-shape, sometimes quadrangular. The stalk
+is variable, sometimes 1 mm. in length. The diameter of the stalk
+increases from the point of attachment to the body of the animal; it
+is usually striated either longitudinally or transversely, or both.
+The tentacles are of two kinds and are usually confined to the
+anterior half of the body. Some are long and sharp-pointed and
+adapted for piercing; others are short, cylindrical, usually
+retracted and capitate, adapted for sucking. Contractile vacuoles
+vary from one to many. The macronucleus is nearly central in position
+and usually of horseshoe shape, but is frequently branched and
+irregular. Reproduction is accomplished by external multiple budding,
+usually from the anterior half of the body. Salt water.</p>
+
+
+<a name="Ephelota_coronata"></a>
+<br>
+<p class="noindent"><b>Ephelota coronata</b> Str. Wright.  Fig. 66.</p>
+
+<p>Synonyms: <i>Hemiophrya gemmipara</i> S. K.; <i>Podophrya gemmipara</i>
+Hertwig.</p>
+
+<p>The body is spheroidal, ovate, or pyriform, with numerous
+sharp-pointed tentacles and a few straight, uniform tentacles. The
+stalk is about three times the length of the body and tapers from its
+widest part at the insertion in the body to the narrowest part at the
+point of attachment. It may or may not be longitudinally striated.
+This is one of the commonest of the <i>Suctoria</i> found at Woods Hole.
+It is usually present on Campanularian hydroids, but may be found on
+algæ and Bryozoa.</p>
+
+<p>Length of body 90&micro; to 200&micro;.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_66.jpg">
+<img src="images/fig_66t.jpg" width="300" border=0
+alt="Ephelota coronata"></a>
+</td><td align="center">
+<b>Fig. 66.&mdash;<br>
+<i>Ephelota coronata</i>.</b>
+<br>
+<br>
+<a href="images/fig_66.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<br>
+<br>
+<br>
+<h3>Genus ACINETA Ehr. '33, B&uuml;tschli '88.</h3>
+
+<div class="center"><span class="syn">(Stein '54, '59;
+Clapar&egrave;de &amp; Lachman '58; Quennerstedt '67;<br>
+Hertwig '76; Mereschowsky '79; Entz '84; Kent '81; Maupas '83;<br>
+Gruber '84;
+Gourret &amp; Roeser '86, and others.)</span></div>
+
+
+<table class="imagetable" align="right"><tr><td>
+<center>
+<a href="images/fig_67.jpg">
+<img src="images/fig_67t.jpg" width="270" border=0
+alt="Acineta divisa"></a><br>
+<b>Fig. 67.&mdash;<i>Acineta divisa</i>.</b>
+<br>
+<br>
+<a href="images/fig_67.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a></center>
+</td></tr></table>
+
+
+<p>Small to medium-sized forms. The distinguishing feature is that the
+stalk is swollen at the distal extremity to form a cup or basin in
+which the animal rests. The cup may be developed until the body is
+nearly inclosed. The macronucleus is spherical or band form. The
+contractile vacuole is usually single. Budding, so far as known, is
+endogenous. Fresh and salt water.</p>
+
+
+<a name="Acineta_divisa"></a>
+<br>
+<p class="noindent"><b>Acineta divisa</b> Fraipont '79.  Fig. 67.</p>
+
+<p>This extremely graceful form is common on Bryozoa at Woods Hole. The
+cup is shaped like a wine glass and is specifically characterized by
+a cup-formed membrane upon which the animal rests. The animal thus
+has the appearance of being suspended on the edge of the cup. The
+stalk is slender and about 4 times the length of the body. The
+tentacles are all capitate and distributed, and about 2-1/2 times the
+body length. They sway back and forth very slowly. The nucleus is
+spherical and central in position. The contractile vacuole lies near
+the periphery.</p>
+
+<p>Length of body 27&micro;; of stalk 100&micro;; of extended tentacle 65&micro;.</p>
+
+
+<a name="Acineta_tuberosa"></a>
+<br>
+<p class="noindent"><b>Acineta tuberosa</b> Ehr.  Fig. 68.</p>
+
+
+<table class="imagetable" align="right"><tr><td align="center">
+<a href="images/fig_68.jpg">
+<img src="images/fig_68t.jpg" width="240" border=0
+alt="Acineta tuberosa"></a>
+</td><td align="center">
+<b>Fig. 68.&mdash;<br>
+<i>Acineta tuberosa</i>.</b>
+<br>
+<br>
+<a href="images/fig_68.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr></table>
+
+
+<p>Large forms of <i>Suctoria</i> with tentacles arranged in fascicles. The
+stalk is variable in length and the cup is frequently so delicate
+that it can barely be made out. A specific characteristic is the
+break in continuity of the cup at different points, and through these
+places the tentacles emerge in bundles. The tentacles are capitate
+and in the Woods Hole form, 15 in number in each of the two bundles.
+The endoplasm is granular and yellowish in color. The coloring matter
+is frequently arranged in patterns. The nucleus is spheroidal. The
+contractile vacuole is in the anterior third of the body about midway
+between the bundles of tentacles. Reproduction not observed.</p>
+
+<p>Length of body 330&micro;.</p>
+
+
+<br>
+<br>
+<br>
+<h3>Genus TRICHOPHRYA Clap. &amp; Lach. '58.</h3>
+
+<div class="center"><span class="syn">(See Kent '81;
+Entz '84; B&uuml;tschli '88; Sand 1901.)</span></div>
+
+<p>Small forms to medium size; no cups or stalks. The body is spherical
+to elongate, usually, however, more or less irregularly lobed and
+changeable. The tentacles are in fascicles which are usually borne
+upon lobed or swollen places. The body is always more or less spread
+out. Contractile vacuoles variable. The macronucleus is spherical,
+elongate, band-formed or horseshoe-shaped. Reproduction takes place
+by endogenous budding, and the swarm spores are flat or lenticular
+with a distinct ciliary girdle. They are frequently parasitic. Fresh
+and salt water.</p>
+
+
+<a name="Trichophrya_salparum"></a>
+<br>
+<p class="noindent"><b>Trichophrya salparum</b> Entz '84.  Fig. 69.</p>
+
+<p class="syn">B&uuml;tschli '88; Schewiakoff '93; <i>Trichophrya ascidiarum</i> Lachmann '59;
+Ren&eacute; Sand 1901.</p>
+
+<p>The body is somewhat cup-form, with a large, flat base. The anterior
+border is rounded, each of the ends being somewhat truncate and
+carrying a bundle of tentacles all capitate and similar. These may be
+continued internally as far as the nucleus (Sand). The cytoplasm is
+uncolored, but may contain some brilliant granules. The nucleus is
+granular, and spherical, band or horseshoe formed.</p>
+
+
+<center>
+<table class="imagetable" align="center"><tr><td>
+<a href="images/fig_69.jpg">
+<img src="images/fig_69t.jpg" width="350" border=0
+alt="Trichophrya salparum"></a>
+</td><td align="center">
+<b>Fig. 69.&mdash;<br>
+<i>Trichophrya salparum</i>.</b>
+<br>
+<br>
+<a href="images/fig_69.jpg">
+<span class="enlarge">&nbsp;ENLARGE&nbsp;</span>
+</a>
+</td></tr>
+</table>
+</center>
+
+
+<p>This species was found by Dr. G. Hunter on the branchial bars of the
+Ascidian <i>Molgula manhattensis</i>, where great numbers of them are
+often parasitic.</p>
+
+<br>
+<br>
+<br>
+<br>
+<hr class="narrow">
+<br>
+<br>
+<br>
+<br>
+
+
+<h3>LIST OF REFERENCES.</h3>
+
+
+
+
+
+<p class="ref">AUERBACH, L. '54. Ueber Encystierung von Oxytricha pellionella. Zeit.
+wiss. Zool., V, 1854.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '55. Ueber die Einzelligkeit der Amoeben. Zeit. wiss. Zool.,
+VII, 1855.</p>
+
+<p class="ref">BALBIANI E. G. '61. Recherches sur les ph&eacute;nom&egrave;nes sexuelles des
+Infusoires. Jour. de la physiol:, IV, 1861.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '85. Sur un Infusoire parasite du sang de l'Aselle aquatique.
+Rec. zool. Suisse, II, 1885.</p>
+
+<p class="ref">BERGH, R. S. '79. <i>Tiarina fusus</i> Cl. &amp; Lach. Vid. Med. f. d. Nat.
+Foren. Kjobenhavn.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '82. Der Organismus der Cilioflagellaten.  Morph. Jahr., VII, p.
+177.</p>
+
+<p class="ref">BRADY, H. B. '79. Report on the Foraminifera dredged by H. M. S.
+<i>Challenger</i> during the years 1873-1876. Challenger Reports, Zoology,
+IX.</p>
+
+<p class="ref">BRANDT, K. '96. Die Tintinnodeen. Bibliot. Zoolog., XX, 1896.</p>
+
+<p class="ref">B&Uuml;TSCHLI, O. '76. Studien &uuml;ber die ersten Entwickelungsvorg. der
+Eizelle, die Zelltheilung, und die Conjugation der Infusorien.
+Abhand. der Senck. naturf. Ges. Freiburg, X, 1876.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '83-'88. Die Protozoen. Bronn's Klassen u. Ord. des Tierreichs.</p>
+
+<p class="ref">CARPENTER, W. B. '56. Researches on the Foraminifera. Phil. Trans.
+(2), p. 547.</p>
+
+<p class="ref">CARTER, H. J. '56. Notes on the fresh-water Infusoria of the island
+of Bombay. Ann. Mag. Nat. Hist. (2), XVIII.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '63. On the coloring matter of the Red Sea. Id. (3), XI.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '63a. On <i>Amœba princeps</i> and its reproductive cells. Id. (3),
+XII.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '64. On fresh-water Rhizopods of England and India. Id. (3),
+XIII, p. 13.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '65. On the fresh- and salt-water Rhizopods of England and
+India. Id. (3), XV, p. 277.</p>
+
+<p class="ref">CIENKOWSKY, L. '55. Bemerkungen &uuml;ber Stein's Acinetenlehre. Bull.
+Phys. Math. Acad., St. Petersburg, XIII, p. 297 (also in Ann. Mag.
+Nat. Hist. (3), XIII).</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '55. Ueber Cystenbildung bei Infusorien. Zeit. wiss. Zool., VI,
+p. 301.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '61. Beitr&auml;ge zur Kenntniss der Monaden. Arch. f. mik. Anat., I,
+1865, p. 203.</p>
+
+<p class="ref">CLAPAR&Egrave;DE, E. '54. On <i>Actinophrys sol</i>. Ann. Mag. Nat. Hist. (2),
+XV, 1854.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '60. Recherches sur les ann&eacute;lides, etc., observ&eacute;s dans les
+H&eacute;brides. M&eacute;m. Soc. phys. d'hist. nat., Gen&egrave;ve, XVI, 1860.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '67. Miscellan&eacute;es zoologiques. Ann. d. sc. nat. zool. (5), VIII,
+1867.</p>
+
+<p class="ref">CLAPAR&Egrave;DE ET LACHMANN '58-'60. Etudes sur les Infusoires et les
+Rhizopodes. M&eacute;m. Inst. gen&egrave;voise, V, VI, VII.</p>
+
+<p class="ref">COHN, F. '54. Beitr&auml;ge z. Entwicklungsges. der Infusorien. Zeit.
+wiss. Zool. III, 1851; IV, 1853.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '57. Ueber Fortpflanzung von <i>Nassula elegans</i> Ehr. Zeit. wiss.
+Zool., IX, 1857, p. 143.</p>
+
+<p class="ref">COSTE, M. '64. D&eacute;veloppement des Infusoires cili&eacute;s dans une
+mac&eacute;ration de foin. Ann. d. ac. nat. zool.(5), II.</p>
+
+<p class="ref">DADAY, E. v. '86.  Ein kleiner Beitrag der Infusorien-Fauna des
+Golfes v. Neapel. Mitt. Zool. St. Neap., VI, p. 481.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '88. Monographie der Familie der Tintinnodeen. Mitt. Zool. St.
+Neap., VIII, p. 473.</p>
+
+<p class="ref">DAVIS, J. '79. On a new species of Cothurnia. Jour. Roy. Mic. Soc.,
+II, 1879.</p>
+
+<p class="ref">DUJARDIN, F. '35. Recherches sur les organismes inf&eacute;rieures. Ann. d.
+sc. nat. zool. (2), IV, p. 343.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '41. Histoire naturelle des Zoophytes infusoires. Paris, 1841.</p>
+
+<p class="ref">EHRENBERG, C. G. '31. Ueber die Entwickelung und Lebensdauer d.
+Infusionsthiere. Abhand. d. Berlin Ak., 1831, p. 1.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '38. Die Infusionsthierchen als vollkommne Organismen. Leipzig,
+1838.</p>
+
+<p class="ref">ENGELMANN, Th. W. '78. Zur Physiologie der Contractilen Vacuolen der
+Infusionsthiere.  Zool. Anz., I, p. 121.</p>
+
+<p class="ref">ENTZ, G. '84. Ueber Infusorien d. Golfes v. Neapel. Mitt. Zool. St.
+Neap., V, p. 289.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '85. Zur naheren Kenntniss der Tintinnodeen. Mitt. Zool. St.
+Neap., VI, p. 185.</p>
+
+<p class="ref">FABRE-DOMERGUE, P. '85. Note sur les Infusoires cili&eacute;s de la baie de
+Concarneau. Jour. d. l'anat. et de la phys., XXI, p. 554.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '91. Mat&eacute;riaux pour servir a l'histoire des Infusoires cili&eacute;s.
+Ann. d. mic., III, 1890-91, p. 49.</p>
+
+<p class="ref">FOL, H. '83. Further contribution to the knowledge of the
+Tintinnodea. Ann. Mag. Nat. Hist. (5), XII, p.73.</p>
+
+<p class="ref">FRANC&Eacute;, R. H. '97. Der organismus der Craspedomonaden. Budapest.</p>
+
+<p class="ref">FROMENTEL. E. DE. '74. Etudes sur les microzoaires, etc. Paris, 1874.</p>
+
+<p class="ref">GOURRET ET ROESER. '88. Contributions &agrave; l'&eacute;tude des Protozoaires de
+la Corse. Arch. d. biol., VIII  p. 139.</p>
+
+<p class="ref">GREEFF, R. '66. Ueber einige in der Erde lebende Amoeben und andere
+Rhizopoden. Arch. f. mik. Anat., II, p. 299.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '70. Untersuchungen ueber den Bau u. d. Naturgeschichte d.
+Vorticellen. Arch. f. Naturges., XXXVI, XXXVII.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '71. Ueber die Actinophryens oder Sonnenthierchen des
+S&uuml;ssenwassers als echte Radiolarien. Sitz. Ber. d. Niederrh. Ges. i.
+Bonn, XXVIII, p. 4.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '75. Ueber Radiolarien u. Radiolarienartige Rhizopoden des
+S&uuml;ssenwassers 2.  Arch. f. mik. Anat., XI.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '88. Studien &uuml;ber Protozoen. Sitz. Ber. Ges. z. Bef. d. ges.
+Nat., Marburg, 1888, p. 91.</p>
+
+<p class="ref">GRENACHER, H. '68.  Ueber <i>Actinophrys sol</i> Ehr. Verh. phys.-med.
+Ges. Freiburg (n. F.), I.</p>
+
+<p class="ref">GRUBER, A. '83. Beobachtungen an <i>Chilodon curvidentis</i> n. sp.
+Festschr. 56. Vers. Deutsch. Naturf. gewid. v. d. Naturf. Ges.
+Freiburg, II, p. 1.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '84. Die Protozoen des Hafens v. Genua. Nova Act. d. K.
+Leop.-Car. Deutsch. Akad. d. Naturf., XLVI, p. 475.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '87. Ueber der Bedeutung der Conjugation bei den Infusorien.
+Ber. d. Naturf. Ges. Freiburg, II, p. 31.</p>
+
+<p class="ref">H&AElig;CKEL, E. '73. Zur Morphologie der Infusorien.  Jena Zeit., VII, p.
+516.</p>
+
+<p class="ref">HERTWIG, R. '76. Ueber <i>Podophrya gemmipara</i>, nebst Bemerkungen zum
+Bau u. d. systemat. Stellung d. Acineten. Morph. Jahr., IV, p. 20.</p>
+
+<p class="ref">HERTWIG U. LESSER. Ueber Rhizopoden u. denselben nahe stehende
+Organismen. Arch. F. mik. Anat., X, Suppl., p. 35.</p>
+
+<p class="ref">HUXLEY, T. H. '57. On Dysteria, a new genus of Infusoria. Jour. Mic.
+Sci., V, p. 78.</p>
+
+<p class="ref">ISHIKAWA, C. Ueber eine in Misaki vorkommende Art v. Ephelota, etc.
+Journ. Coll. Sci. Imp. Univ. Tokyo, Japan, X, pt. 2.</p>
+
+<p class="ref">JAMES-CLARK, H. '66. On the Spongiæ ciliatæ as Infusoria flagellata,
+etc. Mem. Bost. Soc. Nat. Hist. (3), I, p. 1.</p>
+
+<p class="ref">KENT, W. SAVILLE. '81. Manual of the Infusoria. London, 1881.</p>
+
+<p class="ref">KLEBS, G. '84. Ein kleiner Beitrag z. Kenntniss d. Peridineen. Bot.
+Zeit., XLII, p. 721.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '92. Flagellaten Studien 1. Zeit. wiss. Zool., LV.</p>
+
+<p class="ref">LABB&Eacute;, A. '95. Sur les Protozoaires marins de Roscoff. Arch. d. zool.
+exp&eacute;r. (3), N. et R., p. XIV.</p>
+
+<p class="ref">LAUTERBORN, R. '94. Beitr&auml;ge z. S&uuml;sswasserfauna der Insel Helgoland.
+Wiss. Meeresunt. Komm. wiss. Unt. d. Meere Kiel (2), I, p. 215.</p>
+
+<p class="ref">LEIDY, J. '77. Remarks upon Rhizopods and notice of a new form. Proc.
+Ac. Sci. Phila., 1877, p. 293.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '79. Fresh water Rhizopods of North America. Washington, 1879.</p>
+
+<p class="ref">LIEBERK&Uuml;HN, N. '56. Ueber Protozoen.  Notes from a letter to C. Th.
+v. Siebold. Zeit. wiss. Zool., VIII, p. 307.</p>
+
+<p class="ref">MAUPAS, E. '81. Contributions &agrave; l'&eacute;tude des Acin&eacute;tiens. Arch. d.
+zool. exp&eacute;r. (1), IX, p. 299.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '83. Contributions &agrave; l'&eacute;tude morphologique et anatomique des
+Infusoires cili&eacute;s. Id. (2), I.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '83a. Les sucto-cili&eacute;s de M. Mereschowsky. Comp. Ren., XCV, p.
+1381.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '88. Recherches exp&eacute;rimentales sur la multiplication des
+Infusoires cili&eacute;s. Arch. d. zool. exper. (2), VI, p. 165.</p>
+
+<p class="ref">MERESKOWSKY, C. '78. Studien &uuml;ber Protozoen des nordlichen Russland.
+Arch. f. mik. Anat., XVI, p. 163.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '81. On some new or little-known Infusoria. Ann. Mag. Nat. Hist.
+(5), VII, 1881.</p>
+
+<p class="ref">MOEBIUS, K. '88. Bruchst&uuml;cke einer Infusorienfauna der Kieler Bucht.
+Arch. f. Naturg., 1888.</p>
+
+<p class="ref">PECK, J. I. '93. On the food of the menhaden. Bull. U. S. Fish Com.,
+1893, p. 113.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '95. The sources of marine food. Bull. U. S. Fish Com., 1895, p.
+351.</p>
+
+<p class="ref">PERTY, M. '49. Mikrosk. Organ. der Alpen u. d. Italien. Schweiz.
+Mitt. d. Naturf. Ges. in Bern, 164-165.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '52. Zur Kenntniss kleinster Lebensformen, etc., Bern.</p>
+
+<p class="ref">POUCHET, G. '83; '85. Contributions &agrave; l'histoire des P&eacute;ridiniens
+marins. Jour. de l'anat. et de la phys., XIX, XXI.</p>
+
+<p class="ref">QUENNERSTEDT, A. '65; '67; '69. Bidrag till Sveriges Infusorie-fauna.
+Lunds Univ. &Auml;rsskrift, II, IV, VI.</p>
+
+<p class="ref">SAND, R. 1901. Etude monographique sur le groupe des Infusoires
+tentaculif&egrave;res. Ann. d. la Soc. belge de microscopie, XXIV, XXV,
+XXVI.</p>
+
+<p class="ref">SCHAUDINN, F. '95. Die Heliozoen. Das Tierreich, 1895.</p>
+
+<p class="ref">SCHEWIAKOFF, W. '89. Beitr&auml;ge z. Kenntniss der Holotrichen Ciliaten.
+Bib. Zool., V, p. 1.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '93. Ueber einige ecto- u. ento-parasitische Protozoen der
+Cyclopiden. Bull. Soc. nat. Moscou, 1893. I.</p>
+
+<p class="ref">SCHUETT, F. '95. Die Peridineen d. Plankton-Expedition, 1. Kiel u.
+Leipzig.</p>
+
+<p class="ref">SCHULTZE, F. E. '74; 75. Rhizopodenstudien. Arch. f. mik. Anat., X,
+XI, XIII.</p>
+
+<p class="ref">SCHULTZE, M.  '62. Ueber d. Organismus d. Polythalamien. Leipzig,
+1862.</p>
+
+<p class="ref">SHEVYAKOV ?. '96. Monograph on <i>Holotrichous ciliates</i>. (In Russian.)
+Mem. of the St. Petersburg Acad., VII.</p>
+
+<p class="ref">STEIN, F. '59; '78; '83. Der Organismus der Infusionsthiere. I.
+Infusoria, '59; II. Infusoria, '78; III. Flagellata, '83.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '49. Untersuchung &uuml;ber die Entwicklungs d. Infusorien. Arch. f.
+Natur., I, p. 92.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '54. Die Infusionsthiere auf ihre Entwicklungsgeschichte
+untersucht. Leipzig, 1854.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '60. Ueber <i>Leucophrys patula</i> u. &uuml;ber 2 neue
+Infusoriengattungen Gyrocoris u. Lophomonas. Sitz. Ber. d. K.-böhm.
+Ges. d. Wiss. d. Prag, 1860, p. 4.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '64. Ueber die neue Gattung Epiclintes. Id., 1864, I.</p>
+
+<p class="ref">STERKI, V. '78. Beitr&auml;ge z. Morphologie der Oxytrichinen.  Zeit.
+wiss. Zool., XXXI, p. 29.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '98. On the classification of ciliate Infusoria. Amer. Natur.,
+XXXII, p. 425.</p>
+
+<p class="ref">STEVENS, N. M. 1901. Studies on ciliate Infusoria.  Proc. Calif.
+Acad. Sciences, III, 1.</p>
+
+<p class="ref">STOKES, A. C. '84. Notices of some new parasitic Infusoria. Amer.
+Nat., XVIII, p. 1081.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '85. Some apparently undescribed Infusoria from fresh water.
+Id., XIX, p. 18.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '87. Some new hypotrichous Infusoria from American fresh waters.
+Ann. Mag. Nat. Hist. (5), 20.</p>
+
+<p class="ref">TATEM, T. G. '67. New species of microscopic animals.  Q. J. M. S.
+(n.s.), VII, p. 251.</p>
+
+<p class="ref">VEJDOWSKY, F. '79. Monographie der Enchytraeiden.  Prag, 1869.</p>
+
+<p class="ref">WALLENGREN, H. '94. Studier ofver ciliata Infusorier, 1. Slagtet
+Lichnophora. Lund, 1894.</p>
+
+<p class="ref">WALLICH, G. C. '63. Observations on an undescribed indigenous Amœba.
+Ann. Mag. Nat. Hist. (3), XI, XII.</p>
+
+<p class="ref">WESTON, J. '56. On the <i>Actinophrys sol</i>. Q. J. M. S., IV, p. 116.</p>
+
+<p class="ref">WRZESNIOWSKI A. '61. Observations sur quelques Infusoires. Ann. d.
+sc. nat. zool. (6), XVI.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '69. Ein Beitrag zur Anatomie der Infusorien. Arch. f. mik.
+Anat., V, p. 25.</p>
+
+<p class="ref">&ndash;&ndash;&ndash;&ndash; '70. Beobachtungen &uuml;ber Infusorien a. d. Umgebung v. Warschau.
+Zeit. wiss. Zool., XX, p. 467.</p>
+
+
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+Project Gutenberg (https://www.gutenberg.org) public repository for
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+The Project Gutenberg eBook, Marine Protozoa from Woods Hole, by Gary N.
+Galkins
+
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+
+
+
+Title: Marine Protozoa from Woods Hole
+       Bulletin of the United States Fish Commission 21:415-468, 1901
+
+
+Author: Gary N. Galkins
+
+
+
+Release Date: May 5, 2006  [eBook #18320]
+
+Language: English
+
+Character set encoding: ISO-8859-1
+
+
+***START OF THE PROJECT GUTENBERG EBOOK MARINE PROTOZOA FROM WOODS HOLE***
+
+
+E-text prepared by Ronald Calvin Huber, while serving as Penobscot Bay
+Watch, Rockland, Maine, and Joseph E. Loewenstein, M.D.
+
+
+
+Note: Project Gutenberg also has an HTML version of this
+      file which includes the original illustrations.
+      See 18320-h.htm or 18320-h.zip:
+      (https://www.gutenberg.org/dirs/1/8/3/2/18320/18320-h/18320-h.htm)
+      or
+      (https://www.gutenberg.org/dirs/1/8/3/2/18320/18320-h.zip)
+
+
+
+
+
+Contributions from the Biological Laboratory of the U. S. Fish
+Commission, Woods Hole, Massachusetts.
+
+MARINE PROTOZOA FROM WOODS HOLE.
+
+by
+
+GARY N. GALKINS,
+Department of Zoology, Columbia University.
+
+_Bulletin of the United States Fish Commission_ 21:415-468, 1901
+
+
+
+
+
+
+Comparatively little has been done in this country upon marine
+Protozoa. A few observations have been made by Kellicott, Stokes, and
+Peck, but these have not been at all complete. With the exception of
+Miss Stevens's excellent description of species of _Lichnophora_ I
+am aware of no single papers on individual forms. Peck ('93 and '95)
+clearly stated the economic position of marine Protozoa as sources of
+food, and I need not add to his arguments. It is of interest to know
+the actual species of various groups in any locality and to compare
+them with European forms. The present contribution is only the
+beginning of a series upon the marine Protozoa at Woods Hole, and
+the species here enumerated are those which were found with the algæ
+along the edge of the floating wharf in front of the Fish Commission
+building and within a space of about 20 feet. Many of them were
+observed in the water and algæ taken fresh from the sea; others
+were found only after the water had been allowed to stand for a few
+days in the laboratory. The tow-net was not used, the free surface
+Protozoa were not studied, nor was the dredge called into play. Both
+of these means of collecting promise excellent results, and at some
+future time I hope to take advantage of them.
+
+My observations cover a period of two months, from the 1st of July
+to the 1st of September. During that time I was able to study and
+describe 72 species representing 55 genera, all from the limited
+space mentioned above. In addition to these there are a few genera
+and species upon which I have insufficient notes, and these I shall
+reserve until opportunity comes to study them further.
+
+I take this opportunity to express my thanks to Dr. Hugh M. Smith
+for many favors shown me while at Woods Hole.
+
+In dealing with these marine forms from the systematic standpoint,
+two courses are open to the investigator. He may make numerous new
+species based upon minor differences in structure, or he may extend
+previous descriptions until they are elastic enough to cover the
+variations. The great majority of marine protozoa have been described
+from European waters, and the descriptions are usually not elastic
+enough to embrace the forms found at Woods Hole. I have chosen,
+however, to hold to the conservative plan of systematic work, and to
+make as few new species as possible, extending the older descriptions
+to include the new forms.
+
+The different classes of Protozoa, and orders within the classes,
+are distributed more or less in zones. Thus the Infusoria, including
+the Ciliata and the Suctoria, are usually littoral in their habitat,
+living upon the shore-dwelling, or attached, water plants and upon
+the animals frequenting them. It is to be expected, therefore,
+that in forms here considered there should be a preponderance of
+Infusoria. Flagellated forms are also found in similar localities,
+but on the Surface of the sea as well; hence the number described
+in these pages is probably only a small proportion of the total
+number of Mastigophora in this region. The Sarcodina, including the
+Foraminifera and the Radiolaria, are typically deep-sea forms and
+would not be represented by many types in the restricted locality
+examined at Woods Hole. Two species, _Gromia lagenoides_ and
+_Truncatulina lobatula_, alone represent the great order of
+Foraminifera, while the still larger group of Radiolaria is not
+represented at all.
+
+The Protozoa described are distributed among the different orders as
+follows:*
+
+
+Class SARCODINA.
+   Subclass RHIZOPODA.
+      Order AMOEBIDA.
+            1. _Amoeba guttula_ Duj
+            2. _Amoeba_ sp.
+            3. _Trichosphærium sieboldi_ Schn.
+      Order RETICULARIIDA.
+         Suborder IMPERFORINA.
+            4. _Gromia lagenoides_ Gruber.
+         Suborder PERFORINA.
+            5. _Truncatulina lobatula_ Walker & Jacob.
+   Subclass HELIOZOA.
+      Order APHROTHORACIDA.
+            6. _Actinophrys sol_ Ehr.
+      Order CHLAMYDOPHORIDA.
+            7. _Heterophrys myriapoda_ Archer.
+Class MASTIGOPHORA.
+   Subclass FLAGELLIDIA.
+      Order MONADIDA.
+            8. _Mastigamoeba simplex_, n. sp.
+            9. _Codonoeca gracilis_, n. sp.
+           10. _Monas_ sp.
+      Order CHOANOFLAGELLIDA.
+           11. _Monosiga ovata_ S. Kent.
+           12. _Monosiga fusiformis_ S. Kent.
+           13. _Codonosiga botrytis_ (Ehr.) J. Cl.
+      Order HETEROMASTIGIDA.
+           14. _Bodo globosus_ Stein.
+           15. _Bodo caudatus_ (Duj.) Stein.
+           16. _Oxyrrhis marina_ Duj.
+      Order EUGLENIDA.
+           17. _Astasia contorta_ Duj.
+           18. _Anisonema vitrea_ Duj.
+      Order SILICOFLAGELLIDA.
+           19. _Distephanus speculum_ Stöhr.
+   Subclass DINOFLAGELLIDIA.
+      Order ADINIDA.
+           20. _Exuviælla lima_ Clenk.
+           21. _Exuviælla marina_ Clenk.
+      Order DINIFERIDA.
+           22. _Gymnodinium gracile_ Bergh.
+           23. _Glenodinium cinctum_ Ehr.
+           24. _Glenodinium compressa_, n. sp.
+           25. _Peridinium digitale_ Pouchet.
+           26. _Peridinium divergens_ Ehr.
+           27. _Ceratium tripos_ Nitsch.
+           28. _Ceratium fusus_ Ehr.
+           29. _Amphidinium operculatum_ Clap. & Lach.
+Class INFUSORIA.
+   Subclass CILIATA.
+      Order HOLOTRICHIDA.
+         Family ENCHELINIDÆ.
+           30. _Lacrymaria lagenula_ Cl. & Lach.
+           31. _Lacrymaria coronata_ Cl. & Lach.
+           32. _Trachelocerca phoenicopterus_ Cohn.
+           33. _Tiarina fusus_ Cl. & Lach.
+           34. _Mesodinium cinctum_, n. sp.
+         Family TRACHYLINIDÆ.
+           35. _Lionotus fasciola_ Ehr.
+           36. _Loxophyllum setigerum_ Quenn.
+         Family CHLAMYDODONTIDÆ.
+           37. _Nassula microstoma_ Cohn.
+           38. _Chilodon cucullulus_ Müll.
+           39. _Dysteria lanceolata_ Cl. & Lach.
+         Family CHILIFERIDÆ.
+           40. _Frontonia leucas_ Ehr.
+           41. _Colpidium colpoda_ Ehr.
+           42. _Uronema marina_ Duj.
+         Family PLEURONEMIDÆ.
+           43. _Pleuronema chrysalis_ Ehr.
+           44. _Pleuronema setigera_, n. sp.
+           45. _Lembus infusionum_, n. sp.
+           46. _Lembus pusillus_ Quenn.
+         Family OPALINIDÆ.
+           47. _Anoplophrya branchiarum_ Stein.
+      Order HETEROTRICHIDA.
+         Family BURSARIDÆ.
+           48. _Condylostoma patens_ Müll.
+         Family HALTERIDÆ.
+           49. _Strombidium caudatum_ From.
+         Family TINTINNIDÆ.
+           50. _Tintinnopsis beroidea_ Stein.
+           51. _Tintinnopsis davidoffi_ Daday.
+      Order HYPOTRICHIDA.
+         Family PERITROMIDÆ.
+           52. _Peritromus emmæ_ Stein.
+         Family OXYTRICHIDÆ.
+           53. _Epiclintes radiosa_ Quenn.
+           54. _Amphisia kessleri_ Wrzes.
+         Family EUPLOTIDÆ.
+           55. _Euplotes charon_ Ehr.
+           56. _Euplotes harpa_ Stein.
+           57. _Diophrys appendiculatus_ Stein.
+           58. _Uronychia setigera_, n. sp.
+           59. _Aspidisca hexeris_ Quenn.
+           60. _Aspidisca polystyla_ Stein.
+      Order PERITRICHIDA.
+         Family LICHNOPHORIDÆ.
+           61. _Lichnophora macfarlandi_ Stevens.
+         Family VORTICELLIDÆ.
+           62. _Vorticella marina_ Greeff.
+           63. _Vorticella patellina_ Müller.
+           64. _Zoothamnium elegans_ D'Udek.
+           65. _Cothurnia crystallina_ Ehr.
+           66. _Cothurnia nodosa_ Cl. & Lach.
+           67. _Cothurnia imberbis_ Ehr.
+   Subclass SUCTORIA.
+         Family PODOPHRYIDÆ.
+           68. _Podophrya gracilis_, n. sp.
+           69. _Ephelota coronata_ Wright.
+         Family ACINETIDÆ.
+           70. _Acineta divisa_ Fraip.
+           71. _Acineta tuberosa_ Ehr.
+         Family DENDROSOMIDÆ.
+           72. _Trichophrya salparum_ Entz.
+
+* This classification includes only the orders and families
+  represented at Woods Hole
+
+
+
+Genus AMOEBA Auct.
+
+The pseudopodia are lobose, sometimes absent, the body then
+progressing by a flowing movement; the body consists of ectoplasm and
+endoplasm, the latter being granular and internal, the former hyaline
+and external. There is always one nucleus and one vacuole, but both
+may be more numerous. Reproduction takes place by division or by
+spore-formation. Fresh-water and marine.
+
+
+Amoeba guttala Duj.  Fig. 1.
+
+A minute form without pseudopodial processes, extremely hyaline in
+appearance, and characterized by rapid flowing in one direction.
+The body is club-shape and moves with the swollen end in advance.
+A comparatively small number of large granules are found in the
+swollen portion, while the smaller posterior end is quite hyaline.
+Contractile vacuole absent, and a nucleus was not seen.  Frequent in
+decomposing vegetable matter. Length 37µ. Traverses a distance of
+160µ in one minute.
+
+The fresh-water form of _A. guttula_ has a vacuole, otherwise
+Dujardin's description agrees perfectly with the Woods Hole forms.
+
+
+[Illustration: Fig. 1.--_Amoeba guttala_.]
+
+
+Amoeba?  Fig. 2.
+
+A more sluggish form than the preceding, distinguished by its larger
+size, its dense granulation, and by short, rounded pseudopodia,
+which, as in _Amoeba proteus_, may come from any part of the body.
+A delicate layer of ectoplasm surrounds the granular endoplasm, and
+pseudopodia formation is eruptive, beginning with the accumulation
+of ectoplasm. Movement rapid, usually in one direction, but may be
+backwards or sideways, etc. Contractile vacuole absent; the nucleus
+is spherical and contains many large chromatin granules. Length 80µ;
+diameter 56µ.
+
+
+[Illustration: Fig. 2.--_Amoeba_ sp.]
+
+
+Genus TRICHOSPHÆRIUM Schneider '78
+
+Synonym: _Pachymyxa hystrix_ Gruber.
+
+Marine rhizopods, globular or irregular in form, and slow to change
+shape. Dimorphic. Both forms multinucleate during vegetative life.
+Pseudopodia are long, thin, and thread-form, with rounded ends.
+Their function is neither food-getting nor locomotion, but probably
+tasting. The plasm of both forms is inclosed in a soft gelatinous
+membrane. In one form the jelly is impregnated with needles of
+magnesium carbonate (Schaudinn), but these are absent in the other
+form. The membrane is perforated by clearly defined and permanent
+holes for the exit of the pseudopodia. Reproduction occurs by
+division, by budding or by fragmentation, but the parts are
+invariably multinucleate. At the end of vegetative life the
+needle-bearing form fragments into numerous mononucleate parts; these
+develop into adults similar to the parent, but without the spines.
+At the end of its vegetative life this new individual fragments into
+biflagellated swarm-spores which may conjugate, reproducing the form
+with needles. Size up to 2 mm.
+
+
+Trichosphærium sieboldi Schneider.  Fig. 3.
+
+With the characters of the genus. A form which I have taken to be a
+young stage of this interesting rhizopod is described as follows:
+
+A minute, almost quiescent, form which changes its contour very
+slowly. The membrane is cap-like and extends over the dome-shaped
+body, fitting the latter closely. The  endoplasm is granular and
+contains foreign food-bodies. Nucleus single, spherical, and
+centrally located. Pseudopodia short and finger-form, emerging from
+the edge of the mantle-opening and swaying slowly from side to side
+or quiescent. The most characteristic feature is the presence of a
+broad, creeping sole, membranous in nature and hyaline in appearance.
+This membrane is the only evidence of ectoplasm, and it frequently
+shows folds and wrinkles, while its contour slowly changes with
+movements of body. The pseudopodia emerge from the body between this
+membrane and the shell margin. Contractile vacuole absent. Length
+42µ, width 35µ. In decomposing seaweeds, etc.
+
+Only one specimen of this interesting form was seen, and I hesitate
+somewhat in placing it on such a meager basis. It is so peculiar,
+however, that attention should be called to it in the hope of getting
+further light upon its structure and mode of life. Its membranous
+disk recalls the genus _Plakopus_; its mononucleate condition, its
+membranous disk, and the short, sometimes branched, pseudopodia
+make it difficult to identify with any phase in the life-history of
+_Trichosphærium_. I shall leave it here provisionally, with the hope
+that it may be found more abundantly another time.
+
+
+[Illustration: Fig. 3.--_Trichosphærium sieboldi_]
+
+
+Genus GROMIA Dujardin '35.
+
+(Dujardin 1835; M. Schultze '62; F. E. Schultze '74; Leidy '77;
+Bütschli '83; Gruber '84.)
+
+The form is ovoid or globular, and the body is covered by a tightly
+fitting, plastic, chitin shell, which, in turn, is covered by a fine
+layer of protoplasm. The flexibility of the shell makes the form
+variable as in the amoeboid types. The thickness of the shell is
+quite variable. The pseudopodial opening is single and terminal. The
+pseudopodia are very fine, reticulate, granular, and sharply pointed,
+and form a loose network outside of the shell opening. Nucleus single
+or multiple. Contractile vacuole is usually absent. Fresh and salt
+water.
+
+
+Gromia lagenoides Gruber '84.  Fig. 4.
+
+This species is not uncommon about Woods Hole, where it is found upon
+the branches of various types of algæ. The body is pyriform, with the
+shell opening at the larger end. The chitinous shell is hyaline and
+plastic to a slight extent, so that the body is capable of some
+change in shape. The shell is thin and turned inwards at the
+mouth-opening, forming a tube (seen in optical section in fig. 4)
+through which the protoplasm passes to the outside. The walls of this
+tube are thicker than the rest of the shell, and in optical section
+the effect is that of two hyaline bars extending into the body
+protoplasm. A thin layer of protoplasm surrounds the shell and
+fine, branching, pseudopodia are given off in every direction. The
+protoplasm becomes massed outside of the mouth-opening and from here
+a dense network of pseudopodia forms a trap for diatoms and smaller
+Protozoa. The nucleus is spherical and contains one or two large
+karyosomes. The protoplasm is densely and evenly granular, without
+regional differentiation. I have never observed an external layer of
+foreign particles, such as Gruber described in the original species.
+
+Length of shell 245µ; largest diameter 125µ.
+
+
+[Illustration: Fig. 4.--_Gromia lagenoides_.]
+
+
+Genus TRUNCATULINA D'Orbigny.
+
+A group of extremely variable foraminifera in which the shell is
+rotaline; i. e., involute on the lower side and revolute on the upper
+(Brady). The shell is calcareous and coarsely porous in older forms.
+The characters are very inconstant, and Brady gives up the attempt to
+distinguish the group by precise and constant characters.
+
+
+Truncatulina lobatula Walker & Jacob.
+
+Synonyms: See Brady '84 for a long list.
+
+"It is impossible to define by any precise characters the
+morphological range of the present species. Its variations are
+infinite." (Brady, p. 660.)
+
+This very common form, which occurs in all latitudes, was found
+frequently among the algæ at Woods Hole. Its characters are so
+difficult to define that for the present I shall limit my record to
+this brief notice. Size of shell 230µ by 270µ.
+
+
+Genus ACTINOPHRYS Ehr.
+
+
+The body is spherical and differentiated into granular endoplasm and
+vacuolated ectoplasm, but the zones are not definitely separated.
+There is one central nucleus and usually one contractile vacuole. The
+pseudopodia have axial filaments that can be traced to the periphery
+of the nucleus.  Fresh and salt water.
+
+Actinophrys sol Ehr., variety.  Fig. 5.
+
+Synonyms: See Schaudinn '95.
+
+The diameter is about 50µ; the vacuolated ectoplasm passes gradually
+into the granular endoplasm. This is the characterization given _A.
+sol_ by Schaudinn, and it applies perfectly to the freshwater forms.
+If I am correct, however, in placing an _Actinophrys_-like form
+found at Woods Hole in this species, the description will have to
+be somewhat modified. In this form (fig. 5) there is no distinction
+between ectoplasm and endoplasm, and there is an entire absence of
+vacuoles. The nucleus is central, and axial filaments were not seen.
+The single specimen that I found looked much like a Suctorian of
+the genus _Sphærophrya_, but the absence of a firm cuticle and the
+presence of food-taking pseudopodia with granule-streaming makes it a
+very questionable Suctorian, and 1 place it here until further study
+throws more light upon it.
+
+Diameter of body 40µ; length of pseudopodia 120 to 140µ.
+
+
+[Illustration: Fig. 5.--_Actinophrys sol_.]
+
+
+
+Genus HETEROPHRYS Archer.
+
+The body is globular with but slight differentiation into ectoplasm
+and endoplasm; one nucleus in the latter; contractile vacuoles
+one or many; pseudopodia on all sides, thin, and with peripheral
+granule-streaming; surrounded by a globular, rather thick coat of
+jelly, which is hyaline inside and granular on the periphery. Fresh
+and salt water.
+
+
+Heterophrys myriapoda Archer.  Fig. 6.
+
+Synonym: _H. marina_ Hert. & Less. '74.
+
+Diameter 25 to 80µ; pseudopodia twice as long as the body diameter;
+the plasm often contains chlorophyll bodies (Zoochlorella). The
+granular part of the gelatinous layer is thick (up to 10µ). The
+spine-like processes are very thin and short. (Schaudinn '95.) The
+marine form found at Woods Hole probably belongs to this species,
+as described by Schaudinn. The short pseudopodia which give to
+the periphery a fringed appearance are quite regularly placed in
+connection with the pseudopodia. The latter are not so long as twice
+the body diameter, the longest being not more than equal to the
+diameter of the sphere. The body inside of the gelatinous covering
+is thickly coated with bright yellow cells similar to those
+on Radiolaria. The animal moves slowly along with a rolling
+motion similar to that described by Pènard '90, in the case of
+_Acanthocystis_. Diameter of entire globe 35µ; of the body without
+the jelly 18µ. The extremely fine granular pseudopodia are 8 to 35µ
+long. Common among algæ.
+
+This form was probably meant by Peck '95, when be figured "a
+heliozoön."
+
+
+[Illustration: Fig. 6.--_Heterophrys myriapoda_.]
+
+
+KEY TO ORDERS OF FLAGELLIDIA.
+
+Small, body usually amoeboid; 1 or more   Order MONADIDA.
+flagella; no mouth
+
+Small; plasmic collar around the          Order CHOANOFLAGELLIDA.
+flagellum
+
+With 2 or more flagella; one trails       Order HETEROMASTIGIDA.
+behind
+
+With 3 or more flagella, none of which    Order POLYMASTIGIDA.
+trails
+
+Large; firm body wall; 1 or 2 flagella;   Order EUGLENIDA.
+mouth or pharynx, or both
+
+Medium size; with chlorophyll,            Order PHYTOFLAGELLIDA.
+no mouth, usually colonial
+
+Small; silicious skeleton; parasitic      Order SILICOFLAGELLIDA.
+on Radiolaria or free                     (One genus,
+                                          _Distephanus_ Stöhr)
+
+
+KEY TO THE FAMILIES OF MONADIDA.
+
+No mouth; 1 or 2 flagella: amoeboid       Family _Rhizomastigidæ_
+with lobose or ray-like pseudopodia
+
+Mouth at base of single flagellum;        Family _Cercomonadidæ_
+plastic; no pseudopodia
+
+One flagellum; inclosed in gelatinous     Family _Codonoecidæ_
+or membranous cups
+
+One flagellum; tentacle like process      Family _Bikoecidæ_
+at base of flagellum; inclosed in cup
+
+One main flagellum and 1 or 2             Family _Heteromonadidæ_
+accessory flagella
+
+
+KEY TO MARINE GENERA OF MONADIDA.*
+
+Family _Rhizomastigidæ_:
+
+   1. Flagellum repeatedly thrown off     Genus *_Mastigamoeba_
+      and reassumed                       in part
+
+   2. Flagellum never thrown off          3
+
+   3. a. Pseudopodia lobose               Genus _Mastigamoeba_
+
+      b. Pseudopodia ray-like             Genus _Mastigophrys_
+
+Family _Codonoecidæ_:
+
+   1. Goblet-shaped cups adherent         Genus *_Codonoeca_
+      by stalk
+
+Family _Heteromonadidæ_:
+
+   1. The long flagellum vibratory        Genus *_Monas_
+
+   2. The long flagellum rigid;           Genus _Sterromonas_
+      shorter one vibrates
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE QENERA OF CHOANOFLAGELLIDA.
+
+   1. Without gelatinous                  3
+      or membranous test
+
+   2. With gelatinous                     4
+   or membranous test
+
+   3. a. Attached forms:
+
+         1. Without a stalk, or with      Genus *_Monosiga_
+            a very short one
+
+         2. With a long, simple, stalk    Genus *_Codonosiga_
+
+         3. With a long, branched, stalk  Genus _Codonocladium_
+
+      b. Free-swimming                    Genus _Desmarella_
+
+   4. Colonial, and with a gelatinous     Genus _Proterospongia_
+      covering
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO FAMILIES AND MARINE GENERA OF HETEROMASTIGIDA.
+
+   1. Two flagella nearly equal in size   Family _Bodonidæ_
+
+      One main and 2 accessory flagella   Family _Trimastigidæ_
+
+Family _Bodonidæ_:
+
+   1. Body very plastic,                  Genus *_Bodo_
+      almost amoeboid
+
+      Body not plastic; with large        Genus *_Oxyrrhis_
+      anterior cavity, holding flagella
+
+Family _Trimastigidæ_:
+
+   1. With an undulatory membrane         Genus _Trimastix_
+      between accessory flagella
+
+      Without such membrane; flagella     Genus _Costia_
+      contained in a ventral groove
+      while at rest
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF POLYMASTIGIDA.
+
+   1. Body flattened; ends rounded;       Genus _Trepomonas_
+      sides hollowed; often with
+      wing-like processes; cross
+      section S-shaped
+
+   2. Body pyriform; one large            Genus _Tetramitus_
+      asymmetrical groove; 4 flagella
+
+   3. Body spherical; many flagella       Genus _Multicilia_
+      equally distributed
+
+
+KEY TO FAMILIES AND MARINE GENERA OF EUGLENIDA.
+
+   1. With deeply-insunk pharynx;         2
+      no mouth
+
+      With pharynx and distinct mouth     Family _Peranemidæ_
+
+   2. Body plastic; usually with          Family _Euglenidæ_
+      chromatophores and eye-spot
+
+      Body plastic; no chromatophores;    Family _Astastidæ_
+      no eye-spot
+
+Family _Euglenidæ_:
+
+      Body _Euglena_-like, inclosed       Genus _Trachelomonas_
+      in shell with round opening for
+      exit of flagellum
+
+Family _Astastidæ_:
+
+      Body with one flagellum             Genus *_Astasia_
+
+Family _Peranemidæ_:
+
+   1. Body striped; plastic;              Genus _Heteronema_
+      two diverse flagella
+
+   2. Body striped; not plastic;          Genus *_Anisonema_
+      posterior flagellum longer
+      than the other
+
+   3. Body striped; not plastic;          Genus _Entosiphon_
+      with rod-like organ in pharynx
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus MASTIGAMOEBA F. E. Schultze '75.
+
+(Kent '81; Bütschli '86; Klebs '92; Senn 1900.)
+
+In general the form is oval and either regular in outline or
+irregular through the presence of many pseudopodia. One flagellum
+usually quite large and distinct. Differentiation of ectoplasm and
+endoplasm distinct or wanting. One to several contractile vacuoles.
+The pseudopodia are occasionally withdrawn, and the flagellum is the
+sole means of locomotion. In some cases the flagellum turns into a
+pseudopodium, and, conversely, the pseudopodium at one end may become
+a flagellum (see below). In some rare cases the ectoplasm secretes a
+gelatinous mantle. Reproduction not observed.
+
+Fresh and salt water.
+
+
+Mastigamoeba simplex, n. sp.  Fig. 7.
+
+A very small form, first seen in the flagellated stage, aroused my
+interest by reason of the fact that its flagellum lost its regular
+outline and became amoeboid, turning to a pseudopodium, while at the
+same time other pseudopodia were protruded from different parts of
+the periphery. In this condition ectoplasm and endoplasm could be
+made out with the clearest definition. After the pseudopodia were
+well formed, the body became flat and closely attached to the glass
+slide. In a short time one of the pseudopodia became longer than the
+rest; the body became more swollen; the pseudopodia were gradually
+drawn in, with the exception of the more elongate one; this became
+active in movement and finer in diameter, until ultimately it formed
+a single flagellum at the anterior of a small monadiform flagellate.
+The process was repeated two or three times under my observation,
+so that I am convinced that it was not a developmental form of
+some rhizopod. Several of them were seen at different times during
+the summer, and they were always of the same size and form in
+the flagellated or amoeboid condition. I did not make out their
+reproduction, and I shall not be satisfied that this is a good
+species until their life history is known.
+
+In decaying algæ. Length 10µ.
+
+
+[Illustration: Fig. 7.--_Mastigamoeba simplex_.]
+
+
+Genus CODONOECA James Clark '66.
+
+(Kent '81.)
+
+Small forms inclosed in cup or "house" of ovoid or goblet shape,
+colorless and probably gelatinous (chitin?) in texture, and borne
+upon a stalk. The monad does not completely fill the test.
+Contractile vacuole single, posterior.
+
+
+Codonoeca gracilis, n. sp.  Fig. 8.
+
+The cup is urn-shaped with a well-defined neck or collar borne upon a
+shoulder-like end of the body. It is hyaline, colorless, and carried
+upon a stalk equal in length to the cup or shorter than this. The
+animal does not fill the cup, nor is it attached by a filament to
+the latter. There is a single flagellum. The nucleus is minute and
+lateral in position; the contractile vacuole is in the posterior end
+of the body. Total length of cup and stalk 21µ; of cup alone 12µ.
+This minute form looked so much like a choanoflagellate that I
+supposed it to be one until I discovered an empty case (Fig. 8).
+
+
+[Illustration: Fig. 8.--_Codonoecea gracilis_.]
+
+
+
+Genus MONAS (Ehr.) Stein '78
+
+(Kent '81; Bütschli '86; Klebs '97; Senn 1900.)
+
+The body is small, globular or oval and either free-swimming or
+fastened by one of the two flagella. The body is sometimes a little
+amoeboid, with short pseudopodial processes. In addition to the main
+flagellum, there are usually one or two small flagella at the basis
+of the larger one.  The nucleus is usually anterior, and one or two
+contractile vacuoles are present.
+
+
+Monas sp.  Fig. 9.
+
+An extremely small form (3µ) attached by a thread of
+protoplasm--perhaps a flagellum, to algæ. The body is ovoid and
+the main flagellum is about four times the length of the body. The
+contractile vacuole is posterior. Only one specimen was seen and
+upon this I shall not attempt to name the species.
+
+
+[Illustration: Fig. 9.--_Monas_ sp.]
+
+
+Genus MONOSIGA Kent '81.
+
+(Bütschli '86; Francé '97; Senn 1900.)
+
+Small colorless forms of Choanoflagellida, always naked and solitary.
+The posterior end is attached directly to the substratum, or
+there is a short stalk not exceeding the body in length. Kent '81
+distinguished nine species, but Bütschli questioned the accuracy
+of many of these, and in this he was followed by Francé '97, who
+recognized three species--_Monosiga ovata_, _M. fusiformis_, and _M.
+augustata_. Fresh and salt water.
+
+
+Monosiga ovata S. Kent '81.  Fig. 10.
+
+Synonyms: _M. brevipes_ S. K.; _M. consociata_ S. K.; _M. limnobia_
+Stokes.
+
+The individuals are unstalked or provided with a very short stalk
+less than the body in length. The form is spherical or ovate,
+broadest at the base and tapering to the extremity. The collar is
+somewhat variable in size. In the Woods Hole forms it was about
+the length of the body. Oil particles present. Contractile vacuole
+posterior, nucleus anterior.
+
+Fresh and salt water. Length of body without the collar 5µ.
+
+
+[Illustration: Fig.10.--_Monosiga ovata_.]
+
+
+Monosiga fusiformis S. K.  Fig. 11.
+
+Synonyms: _M. steinii_ S. K.; _M. longicollis_ S. K.
+
+The individuals are unstalked, minute, and of a general flask-shape.
+The body is swollen centrally and tapers slightly at each end. There
+is no stalk, the body being fixed by the attenuate posterior end.
+There are two contractile vacuoles and one nucleus, which is situated
+a little above the body center. Fresh and salt water. Length without
+collar 9µ; length of collar 3µ.
+
+
+[Illustration: Fig. 11.--_M. fusiformis_.]
+
+
+Genus CODONOSIGA (Jas. Clark '67).
+
+(Bütschli '78; Kent '81; Francé '97; Senn 1900.)
+
+This genus, as modified by Francé, is distinguished from the
+preceding by the possession of an unbranched stalk much longer than
+the body length. The body is naked and of various shapes, and the
+individuals are solitary or colonial upon a single stalk. Kent '81
+enumerates no less than 10 species, which were cut down by Bütschli
+to 1. Francé admits 4--_C. botrytis_ Jas. Clark; _C. grossularia_;
+_C. pyriformis_, and _C. furcata_, all S. Kent--but regards the
+second and third as merely form varieties of the first.
+
+
+Codonosiga botrytis (Ehr. sp.) Jas. Clark '67.  Fig. 12.
+
+Francé gives the following synonyms: _Epistylia botrytis_ Ehr.;
+_E. digitalis_ Stein, _Zoothamnium parasitica_ Stein; _Anthophysa
+solitaria_ Fresenius; _Codonosiga pulcherrima_ Jas. Clark; _Monosiga
+gracilis_ S. Kent; _M. globulosa_ S. Kent; _Codonosiga pyriformis_
+Kent; _C. grossularia_ Kent; (Francé).
+
+The individuals are small and provided with a long unbranched, or
+terminal, simply split stalk. The individuals are single or colonial.
+The Woods Hole form measured 22µ over all; the body was 5µ, the
+collar 3µ, and the stalk 14µ. No colonies were seen, and only a few
+individuals upon red algæ.
+
+
+[Illustration: Fig. 12.--_Codonosiga botrytis_.]
+
+
+Genus BODO (Ehr.) Stein.
+
+(Stein '59, Bütschli '83; Klebs '92; Senn 1900.)
+
+The body is naked, usually amoeboid in its changes, and provided with
+two flagella, one of which is usually trailed along under and behind
+the animal. The anterior end is usually pointed, with the flagella
+arising from a minute depression; the posterior end is rounded.
+Specific characters very difficult to analyze. Fresh and salt water.
+
+
+Bodo globosus Stein.  Fig. 13.
+
+The body during movement is globular or ovoid, without any anterior
+process. The trailing flagellum is invariably much longer than the
+vibratory one. The contractile vacuole lies in the anterior half of
+the body. Solid food particles are taken in near base of flagella.
+
+Length of body 9 to 12µ; diameter 8 to 11µ. Common.
+
+
+[Illustration: Fig. 13.--_Bodo globosus_.]
+
+
+Bodo caudatus (Duj.) Stein.  Fig. 14.
+
+Synonyms: _Amphimonas caudatus_ Duj.; _Diptomastix caudata_ Kent.
+
+The body is variable in shape, but usually flattened and pointed
+posteriorly. An anterior process is almost always present, and
+below this the flagella are inserted in a minute depression. The
+contractile vacuole is close to the base of the flagella. The
+flagella are about the same size, the anterior one usually somewhat
+longer. Common. Length 12 to 18µ.
+
+This species was seen by Peck '95 and described as a small
+flagellate.
+
+
+[Illustration: Fig. 14.--_Bodo caudatus_.]
+
+
+Genus OXYRRHIS Duj.
+
+(Kent '81; Bütschli '86; Klebs '92; Senn 1900.)
+
+Medium-sized forms, somewhat oval in shape, with a rounded posterior
+end. The anterior end is continued dorsally in a somewhat attenuate
+pointed process. At the base of this process is a large cavity or
+funnel, on the dorsal wall of which, or on a projection from this
+wall, are two equal-size flagella. When at rest, the flagella are
+directed backwards. The nucleus is central. In moving, the posterior
+end is invariably in advance. This genus is exceptional among
+Mastigophora in that division is transverse instead of longitudinal.
+
+
+Oxyrrhis marina Duj.  Fig. 15.
+
+With the characters of the genus. Contractile vacuole not seen.
+Length 28 to 40µ.
+
+
+[Illustration: Fig. 15.--_Oxyrrhis marina_.]
+
+
+Genus ASTASIA Ehr.
+
+Flagellates with one flagellum, a spindle-form body and a high
+degree of plasticity, the contour constantly changing. A distinct,
+usually striped cuticle is invariably present. "Eye-spots" are
+absent. Fresh and salt water.
+
+
+Astasia contorta Duj.  Fig. 16.
+
+_Astasia inflata_ Duj. '41.
+
+The body is colorless, transparent, and flexible. It is largest in
+the center, thence tapering at the two extremities. The surface of
+the cuticle is obliquely striated, giving to the animal a distinctly
+twisted appearance. The contractile vacuole is in the anterior
+neck-like portion of the body. The flagellum is inserted in a
+distinct oesophageal tube, into which the contractile vacuole
+empties. This tube is continued into a deeper pharyngeal apparatus of
+unknown function.
+
+Common in decaying algæ. Length 60µ; greatest diameter 30µ.
+
+
+[Illustration: Fig. 16.--Two aspects of _Astasia contorta_.]
+
+
+Genus ANISONEMA Bütschli
+
+Flagellates with two flagella, of which one is directed forwards and
+is concerned with the locomotion of the animal, while the other is
+directed backwards and drags after the animal when in motion. Body
+slightly compressed dorso-ventrally (fig. 17, section). An oral
+furrow is present on the ventral side and the two flagella originate
+in it (fig. 17, at left). The vacuole is on the left side. Food
+vacuoles are present in the posterior part. The nucleus is central.
+Movement creeping.
+
+Fresh and salt water.
+
+
+Anisonema vitrea (Duj.)  Fig. 17.
+
+Synonyms: _Tropidoscyphus octocostatus_ Stein '83; _Sphenomonas_ Kent
+'81; _Ploeotia vitrea_ Senn 1900.
+
+With the characteristics of the genus. It differs from freshwater
+forms in having eight furrowed surfaces running somewhat spirally
+from the posterior to the oral end. Length 50µ; width 23µ.  This
+attractive flagellate was quite common in decaying algæ at Woods
+Hole; its shaking movement, its peculiar furrowed surfaces, and,
+above all, its perfectly transparent, vitreous appearance, were well
+described by Dujardin. Stein's _Tropidoscyphus octocostatus_ is a
+fresh-water form which may possibly be a distinct species, especially
+as it is described with both flagella directed forwards.
+
+
+[Illustration: Fig. 17.--_Anisonema vitrea_.]
+
+
+Genus DISTEPHANUS  Stöhr.
+
+An aberrant flagellate bearing a single flagellum and a silicious
+skeleton resembling those of the Radiolaria. The skeleton consists
+of two rings of different diameter parallel with one another and
+connected by silicious bars. From the wider ring half a dozen bars
+radiate outwards and a similar number of short thorn-like bars point
+inwards obliquely. The color is yellow, and except for the flagellum
+the form might easily be mistaken for a Radiolarian, as has been the
+case repeatedly.
+
+
+Distephanus speculum Stöhr.
+
+_Dictyocha speculum_ Stöhr; _Dictyocha_ Auc.
+
+With the characters of the genus.
+
+A single specimen only of this very interesting form was seen at
+Woods Hole. It occurred in a collection of tow made near the end of
+the wharf during the evening.
+
+
+KEY TO FAMILIES OF DINOFLAGELLIDIA.
+
+   1. No crossfurrow; two free flagella   Family _Prorocentridæ_
+
+   2. One or more cross-furrows           3
+
+   3. Cross-furrow nearly central         Family _Peridinidæ_
+      (cf. _Oxytoxum_)
+
+      Cross-furrow close to               Family _Dinophysidæ_
+      anterior end
+
+      Several cross-furrows               Family _Polydinidæ_
+      and flagella                        (One genus, _Polykrikos_.)
+
+
+KEY TO MARINE GENERA OF PROROCENTRIDÆ.
+
+Diagnostic characters: The transverse furrow is absent and the two
+flagella arise from the anterior end of the body. The shell may be
+bivalved.
+
+   1. No tooth-like process dorsal        Genus *_Exuviælla_
+      to the flagellum
+
+   2. With tooth-like process dorsal      Genus _Prorocentrum_
+      to the flagellum
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF PERIDINIDÆ.
+
+Diagnostic characters: The cross-furrow is nearly central (see,
+however, _Oxytoxum_); the body may or may not have a shell; the
+shell may or may not be composed of distinct plates; the plates are
+distinguished as _equatorial_ (_i.e._, bordering the cross-furrow),
+_apical_, and _antapical_, while still another, the "rhombic plate",
+may be present, extending from the cross-furrow to the apex.
+
+   1. Without distinct shell              Genus *_Gymnodinium_
+
+      With a distinct shell               2
+
+   2. Shell not composed of definite      3
+      plates
+
+      Shell composed of definite plates   4
+
+   3. Cross-furrow replaced by            Genus _Ptychodiscus_
+      thin-skinned band
+
+      Cross-furrow well defined;          Genus _Protoceratium_
+      reticulate markings raised
+      on shell-surface
+
+      Cross-furrow well defined;          Genus *_Glenodinium_
+      no markings
+
+   4. Two parts of shell equal or         5
+      nearly equal
+
+      Two parts of shell very unequal     11
+
+   5. With transverse flagellum in        6
+      a distinct furrow
+
+      Transverse flagellum not in a       10
+      furrow
+
+   6. With horns, or with wing-like       7
+      processes
+
+      Without processes of any kind       9
+
+   7. Processes small, wing-like,         Genus _Diplopsalis_
+      around flagellum-fissure
+
+      Processes horn-like                 8
+
+   8. Anterior part with 7 equatorial     Genus *_Peridinium_
+      and 1 rhombic plates
+
+      Anterior part with 5 equatorial     Genus _Gonyaulax_
+      and no rhombic plates
+
+      Anterior part with 3 equatorial     Genus *_Ceratium_
+      and no rhombic plates
+
+   9. Anterior part with 14 equatorial    Genus _Pyrophacus_
+      and 1 rhombic plates
+
+      Anterior part with 7 equatorial     Genus _Goniodoma_
+      plates
+
+      Anterior part with 4 equatorial     Genus _Amphidoma_
+      plates
+
+  10. Apical extremity drawn out          Genus _Podolampas_
+      into a tube
+
+      Apical extremity not drawn out      Genus _Blepharocysta_
+      into a tube
+
+  11. Cross-furrow deep, with great       Genus _Ceratocorys_
+      ledge-like walls
+
+
+      Cross-furrow wide, no ledge-like    Genus _Oxytoxum_
+      walls
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF DINOPHYSIDÆ.
+
+Diagnostic characters: The cross-furrow is above the center of the
+body, and its edges, as well as the left edge of the longitudinal
+furrow, are usually produced into characteristic ledges; those of
+the cross-furrow usually form great funnel-like anterior processes,
+while those of the longitudinal furrow usually form great, lateral,
+wing-like processes ornamented by ribs and other markings.
+
+   1. Without shell; longitudinal         Genus *_Amphidinium_
+      furrow may open & close
+
+   2. With shell; longitudinal furrow     3
+      unchangeable
+
+   3. With distinct apical funnel         4
+
+      No apical funnel                    Genus _Phalacroma_
+
+   4. With great wing-like ledge          5
+
+      Ledges very small; body long,       Genus _Amphisolenia_
+      needle-like
+
+   5. Ledge of longitudinal furrow        6
+      extends to posterior end
+
+      Ledge of longitudinal furrow        Genus _Dinophysis_
+      does not extend to posterior end
+      (Recorded by Peck ('93-'95) as very abundant at Woods Hole
+      and in Buzzards Bay.)
+
+   6. Ledge is continued dorsally to      Genus _Ornithocercus_
+      the cross-furrow
+
+      Ledge is not continued dorsally     7
+
+   7. With deep dorsal cavity;            Genus _Citharistes_
+      secondary funnel not notched
+
+      No dorsal cavity; secondary         Genus _Histioneis_
+      funnel deeply notched
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EXUVIÆLLA Cienkowsky '82.
+
+(Klebs '81; Pouchet '83, '86.)
+
+The form varies from globular to ovoid, with occasionally a sharp
+posterior end. Shells are usually somewhat compressed, and consist
+of two valves, which frequently slide one over the other in such a
+manner as to show the structure with great clearness. The right shell
+may have a distinct indentation in the anterior edge. There are two
+lateral, discoid, brown chromatophores, each of which possesses a
+central amylum granule. The nucleus is posterior. Salt water.
+
+
+Exuviælla lima Ehr.  Fig. 18.
+
+Synonyms _Pyxidicula_ Ehr.; _Cryptomonas_ Ehr.; _Prorocentrum lima_
+Kent; _Amphidinium_ Pouchet.
+
+The shell is ovate, rounded and swollen posteriorly. The anterior
+border of both shells is slightly indented. The shell is quite thick.
+The animal moves through the water very slowly. Dark brown in color.
+Length 48µ; width 44µ.
+
+
+[Illustration: Fig. 18.--_Exuviælla lima_.]
+
+
+Exuviaella marina Cienkowsky.  Fig. 19.
+
+A smaller form than the preceding, more elliptical in outline, with
+a thinner shell and with large granules throughout the endoplasm.
+The nucleus is spherical and subcentral in position and possesses a
+distinct central granule. This may be a small variety of _E. lima_.
+
+
+[Illustration: Fig. 19.--_Exuviælla marina_.]
+
+
+Genus GYMNODINIUM Stein '78.
+
+(Bergh '81; Kent '81; Pouchet '83, '85; Entz '84; Schütt '95.)
+
+The general structure of these forms is similar to that of
+_Glenodinium_; the most striking and positive difference is the
+absence of a shell. The animals are, as a rule, spherical, yet they
+may be pointed at the two ends or at one of them. They are also
+frequently flattened dorso-ventrally. The transverse furrow may
+be either circular and straight around the body or may describe a
+spiral course, passing even twice around the body. The flagella
+arise near cross-furrow or, in some cases, in longitudinal furrow.
+Chromatophores may or may not be present and food-taking is holozoic,
+in many cases at least. In some cases ectoplasm and endoplasm can be
+distinguished. Fresh and salt water.
+
+
+Gymnodinium gracile Bergh '82, var. sphærica, n.  Fig. 20.
+
+The body is divided by the transverse furrow into a shorter anterior
+and a longer posterior part. The longitudinal furrow is broader at
+the posterior extremity than at the cross-furrow. The structural
+feature upon which this new variety is made is the unvarying
+plumpness of the body, making it almost spherical, except for
+a slight flattening dorso-ventrally. The nucleus is large and
+ellipsoidal, with characteristic longitudinal markings of chromatin.
+The endoplasm is evenly granular, with a number of large ingested
+food bodies. The color is brown, not rose-red as in Bergh's species,
+nor is the Woods Hole form as large as the latter. Length of body
+68µ; width 55µ. Common.
+
+
+[Illustration: Fig. 20.--_Gymnodinium gracile_, var. _sphærica_.]
+
+
+Genus GLENODINIUM (Ehr.), Stein '83.
+
+(Bergh '82; Bütschli '86; Pouchet '85; Daday '86.)
+
+Small globular forms with two distinct furrows, one transverse around
+the body, the other longitudinal upon the face only. The shell is
+soft and structureless with a distinct aperture near the meeting
+point of the two furrows. The endoplasm usually, but not always,
+contains a bright red eye-spot.
+
+Fresh and salt water.
+
+
+Glenodinium compressa, n. sp.  Fig. 21, a, b, c.
+
+This species resembles _G. acuminata_ of Ehrenberg except that it is
+strongly compressed laterally. The longitudinal furrow extends nearly
+to the extremity of the animal. It begins as a narrow slit and widens
+as it progresses upon the left side; it also becomes much deeper
+on this side and at the bottom of the depression the longitudinal
+flagellum is inserted. The transverse furrow runs evenly around the
+body near the upper pole, giving to the shell almost the aspect of
+an _Amphidinium_. Brown chromatophores may or may not be arranged
+radially about a central amylum granule. One striking characteristic
+is the depth of the two furrows. The nucleus is elongate and somewhat
+curved; it lies against the posterior wall of the rather thick shell.
+Not uncommon.
+
+Length 40µ; breadth 32µ; width 18µ.
+
+The posterior end of the animal is often somewhat pointed and this
+point frequently becomes attached, so that the animal whirls around
+upon it as upon a pivot.
+
+
+[Illustration: Fig. 21 a, b, c.--_Glenodinium compressa_, n. sp.]
+
+
+Glenodinium cinctum Ehr.  Fig. 22.
+
+The body is globular, smooth, and homogeneous.  Brown chromatophores
+arranged radially, each in the form of a cone, the base of which
+rests against the shell while the points turn inward.  A bright-red
+eye-spot may or may not be present; when present it is placed near
+the junction of the two furrows. The longitudinal furrow is small.
+Fresh water and salt.
+
+Length and diameter the same, 21µ.
+
+This species was observed by Peck '93.
+
+
+[Illustration: Fig. 22.--_Glenodinium cinctum_.]
+
+
+Genus PERIDINIUM Ehr. '32, Stein '83.
+
+(Claparède & Lachmann '58; Bergh '81; Pouchet '83; '85; Gourret '88;
+Bütschli '86.)
+
+The form is globular, ovoid or elongate, the apex frequently drawn
+out into a long tube. The transverse and longitudinal furrows are
+quite distinct, the former having often a spiral course about the
+body. The two halves of the body are similar, the posterior being
+somewhat shorter; the anterior half has seven equatorial plates, an
+oral plate, two lateral apical plates, and one or two dorsal plates.
+The two antapical plates frequently have a tooth-like process. The
+bodies are colorless, green or brown.
+
+Fresh and salt water.
+
+
+Peridinium digitale Pouchet.  Fig. 23.
+
+Synonyms: _Protoperidinium digitale_ Pouchet; _Protoperidinium_ Bergh
+p. p.; _P. divergens_ Peck.
+
+The shell is covered with pits of large size. The posterior part
+is hemispherical and surmounted by a single horn or spine. The
+transverse furrow is very oblique, and its two extremities are united
+by a sigmoid longitudinal furrow. The anterior half bears two spines
+or horns of different size, and variable.  The nucleus is spherical
+or ellipsoidal and placed in the posterior half of the shell.
+
+Length 68µ; diameter 54µ. Common.
+
+Although the description of Pouchet's _P. digitale_ differs in some
+respects from a careful description of the Woods Hole form, I think
+the species are the same. The chief difference is in the single horn
+of the posterior half; in Pouchet's form this is furrowed by a narrow
+groove which runs to the S-shaped longitudinal furrow. In the Woods
+Hole form I was unable to make out such a furrow. The flagella, also,
+were not seen. This same form was pictured by Peck '95 as _P.
+divergens_.
+
+
+[Illustration: Fig. 23.--_Peridinium digitale_.]
+
+
+Peridinium divergens Ehr.  Fig. 24.
+
+Synonym: _Ceratium divergens_ Kent.
+
+The shell is spheroidal, widest centrally, attenuate and pointed
+posteriorly; the anterior portion is armed with two short, pointed
+horns, each of them having a toothed process at the basal portion
+of the inner margin. They are frequently colorless and beautifully
+transparent, the body being free from large opaque granules; again
+they are colored brown or yellow. The nucleus is large and elongate
+and finely granular. 75µ long and 68µ in diameter. Common.
+
+
+[Illustration: Fig. 24.--Ventral and dorsal aspects of _Peridinium
+divergens_.]
+
+
+Genus CERATIUM (Schrank).
+
+(Stein '78; Perty '52; Clap & Lach. '58; Bergh '82; Pouchet '83;
+Gourret & Roeser '88; Bütschli '85; Kent '81; Senn 1900; Schütt '98.)
+
+The general shape is a flattened sphere with three long processes
+or horns. The cross-furrow is either spiral or circular; the
+longitudinal furrow is usually wide and occupies the greater part of
+the anterior half of the shell. The shell is thick, reticulate or
+striped, and sometimes provided with short spines; often distinctly
+porous. The anterior half is composed of 3 equatorial and 3 apical
+plates, the latter being continued into the horn-like process. The
+posterior half is composed of 3 equatorial and one apical plate
+continued into the posterior horn. The right posterior plate is
+continued into a similar horn which may remain rudimentary or be
+continued into a considerable process. Similarly the left posterior
+horn is usually developed, but remains small. There may be from 2 to
+3, 4, and 5 horns. Chromatophores usually present, green to yellow
+brown.
+
+Fresh and salt water.
+
+
+Ceratium tripos Ehr.  Fig. 25.
+
+The body is somewhat triangular and bears three horns, two of which
+are shorter than the other one and slightly curved upward.
+
+Length, including the horns, 290µ.
+
+
+[Illustration: Fig. 25.--_Ceratium tripos_.]
+
+
+Ceratium fusus Ehr.  Fig. 26.
+
+Synonym: _Peridinium fusus_ Ehr.
+
+The animal is very elongate, due to the presence of two long horns
+at the extremities of the body. Color, yellow with chromatophores.
+Length 285µ; width 23µ.
+
+Both of these species are common in the tow and in the algæ at the
+edge of the wharf. Both of them are mentioned by Peck in '93 and '95.
+
+
+[Illustration: Fig. 26.--_Ceratium fusus_.]
+
+
+Genus AMPHIDINIUM Clap. & Lach.
+
+The body is ovoid to globular and usually much flattened
+dorso-ventrally. The anterior portion is very much reduced and is
+somewhat head-like or cap-like. The longitudinal furrow extends
+through the entire posterior body length and is apparently capable
+of widening and narrowing. It is probably naked (see here Klebs,
+Pouchet, Bütschli), although Stein maintained that there is a
+delicate cuticle-like shell. Chromatophores of brown or green colors
+present and usually grouped radially about a central amylum granule.
+The nucleus is posterior.
+
+Fresh and salt water.
+
+
+Amphidinium operculatum Clap. & Lach.  Fig. 27.
+
+The body is oval and flattened. The transverse furrow is at the
+extremity (posterior) of the body and the small portion, which is
+thus apparently cut off, is the cap-like or operculum-like structure
+which gives the name to the species. Klebs maintains that the two
+furrows are not connected, but in this he is certainly mistaken,
+provided we have the same species under consideration.  Very common
+about Woods Hole.
+
+Length from 40 to 50µ; width 30µ; thickness 15µ.
+
+
+[Illustration: Fig. 27.--_Amphidinium operculatum_.]
+
+
+
+KEY TO INFUSORIA.
+
+1. With cilia                             Subclass _Ciliata_. 3
+
+2. Without cilia (in adult state)         Subclass _Suctoria_
+   tentacles
+
+3. a. Without a specialized fringe of     Order _Holotrichida_
+      large cilia (ad. zone)
+
+   b. With general covering of cilia      Order _Heterotrichida_
+      + adoral zone
+
+   c. With cilia on ventral side          Order _Hypotrichida_
+      + adoral zone
+
+   d. With cilia in region of adoral      Order _Peritrichida_
+      zone, and about mouth only
+
+
+KEY TO FAMILIES OF THE HOLOTRICHIDA.
+
+A. Mouth closed except during food        1
+   ingestion; no undulating membrane
+
+   Mouth always open; with undulating     2
+   membrane
+
+   1. _Gymnostomina_.
+
+      a. Mouth terminal or subterminal.   Family _Enchelinidæ_
+         Food is swallowed and not
+         introduced by currents
+
+      b. Mouth terminal or subterminal;   Family _Trachelinidæ_
+         body frequently drawn out into
+         long process; mouth may have
+         specialized framework.
+
+      c. Mouth central or posterior;      Family _Chlamydodontidæ_
+         pharynx with supporting
+         framework
+
+   2. _Trichostomina_.
+
+      a. Mouth anterior or central;       Family _Chiliferidæ_
+         pharynx short or absent;
+         peristomial depression faint
+         or absent
+
+      b. Mouth central; pharynx long,     Family _Urocentridæ_
+         tubular; cilia in two broad
+         zones
+
+      c. Mouth posterior; form            Family _Microthoracidæ_
+         asymmetrical; cilia dispersed
+         or limited to oral region
+
+      d. Mouth anterior or central.       _Paramoecidæ_
+         Peristomial depression           (One genus, _Paramoecium_)
+         clearly marked.
+
+      e. Mouth at end of long peristome   Family _Pleuronemidæ_
+         running along ventral side;
+         body dorso-ventrally or
+         laterally compressed; left edge
+         of peristome with great, sail-
+         like undulating membrane
+
+      f. Mouth and pharynx distinct,      Family _Isotrichidæ_
+         posterior; cilia uniform.
+         Parasites in ruminants.
+
+      g. Mouth absent; body vermiform,    Family _Opalinidæ_
+         cilia uniform. Usually
+         parasites.
+
+
+KEY TO MARINE GENERA OF ENCHELINIDÆ
+
+Diagnostic characters: Form ellipsoid or ovoid; the mouth is
+invariably terminal and is usually round--more rarely slit-formed; it
+is closed except when food is taken. An oesophagus when present is a
+short, invariably non-ciliated tube which is usually surrounded by
+a more or less clearly defined buccal armature. The anus is usually
+terminal. Large food particles are swallowed, never introduced by
+currents.
+
+   1. Body naked                          3
+
+   2. Body inclosed in a shell or coat    7
+
+   3. a. Cilia uniform about the entire   4
+         body; body symmetrical
+
+      b. Cilia in the mouth region        5
+         longer than the others; body
+         symmetrical
+
+      c. Bristles, or tentacles, in       6
+         addition to cilia
+
+   4. Mouth terminal; body ellipsoidal    Genus _Holophrya_
+      to ovoid
+
+   5. a. Mouth terminal; body elongate,   Genus _Chænia_
+         flexible, and elastic
+
+      b. Mouth terminal; "neck" highly    Genus *_Lacrymaria_
+         elastic; entire body
+         flexible; conical "head"
+
+      c. Mouth terminal; "neck" highly    Genus *_Trachelocerca_
+         elastic; entire body
+         flexible; "head" square
+
+      d. Mouth terminal; "neck" highly    Genus _Lagynus_
+         elastic; no separate
+         mouth-bearing portion
+
+   6. a. Body asymmetrical; bristles      Genus _Stephanopogon_
+         in addition to cilia
+
+      b. Body symmetrical; 4 small        Genus *_Mesodinium_
+         tentacles from mouth; cilia
+         and cirri in girdles
+
+   7. Shell composed of small             Genus *_Tiarina_
+      sculptured pieces; cilia long,
+      uniform
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LACRYMARIA Ehr. '30.
+
+(Ehrenberg, C. G., 1838; Perty '52; Claparède & Lachmann '58; Stein
+59-83; Quennerstedt '66, '67; Fromentel '74; Kent '81; Gruber '84;
+Gourret & Roeser '86; Bütschli '88; Schewiakoff '89.)
+
+Body short to very long flask-shape; for the most part contractile,
+especially in the neck region. The posterior end is rounded or
+pointed. The main character is the mouth-bearing apex, which "sets
+like a cork in the neck of the flask." One or more circles of long
+cilia at the base of the mouth portion or upon it. The body is
+spirally striped. Contractile vacuole terminal, with sometimes one
+or two further forward. Macronucleus central, globular to elongate,
+sometimes double. Food mainly bacteria. Fresh and salt water.
+
+
+Lacrymaria lagenula Clap. & Lach.  Fig. 28, a, b.
+
+Synonym: _L. tenuicula_ Fromentel '74.
+
+Body more or less flask-shape, two or three times as long as broad,
+with conical apex, which is slightly elastic and protrusible; surface
+obliquely striate, with well-defined lines, 14 to 16 in number; cilia
+uniform on the body, with a crown of longer ones at the base of the
+conical proboscis. The body cilia are not thickly placed except
+around the proboscis. The endoplasm is thickly packed with large
+granules (food particles) in the anterior half and with finely
+granular particles in the posterior half. The elongate macronucleus
+lies a little above the center among the larger granules; the
+contractile vacuole is double, one on each side of the median line
+and at the posterior end of the body among the finer granules. The
+anus is posterior. Length 90µ to 160µ; greatest width assumed 65µ.
+When fully expanded the posterior end assumes a curious polyhedral
+form. (Fig. 28 b.)
+
+This form differs slightly from others of the same species as
+described by different observers, the most striking difference being
+the presence of two contractile vacuoles in place of the usual one.
+These are very slow to fill and grow to a large size before diastole.
+The membrane is very tough and retains its form easily under pressure
+of the cover glass. Another characteristic feature is the flattening
+of the surfaces between the striæ. Decaying algæ.
+
+
+[Illustration: Fig. 28.--_Lacrymaria lagenula_.]
+
+
+Lacrymaria coronata Cl. & Lach. '58.  Fig. 29.
+
+Synonyms: _L. lagenula_ Cohn '66; Möbius '88; _L. cohnii_ ? Kent '81;
+_L. versatilis_ Quen. '67.
+
+Form flask-like and similar to _L. lagenula_, contractile but tough.
+The contractile vacuole is terminal, the proboscis is short, slightly
+raised and separated from the body by a deep cleft; the buccal cilia
+are inserted part way up on the proboscis. Form changeable, from
+short, sac-like to elongate and vermiform. Length 85µ.
+
+This species is not very different from _L. lagenula_, but I noted
+that in addition to the elongate nucleus, the body striæ are much
+more apparent here and seem to sink into the cuticle, giving the
+periphery, especially at the collar region, a curious crenulated
+effect. The endoplasm is very densely granular and colored a
+blue-green, probably from food particles. The number of striæ is much
+larger than in the preceding species. The membrane is very tough and
+retains the shape of the body, even with the full pressure of the
+cover glass. Micronucleus and trichocysts were not observed.
+
+
+[Illustration: Fig. 29.--_Lacrymaria coronata_.]
+
+
+Genus TRACHELOCERCA (Ehr. '83) Cohn '66.
+
+(Quennerstedt '67; Gruber '87; Entz '84; Kent '81; Gourret & Roeser
+'88; Bütschli '88; Schewiakoff '89; Shevyakov '96.)
+
+The only well-known representative is very elongate, large (up
+to 3 mm. Van Beneden), and very contractile. The main feature of
+importance in distinguishing it is the 4-part structure of the mouth
+region, which, however, may not be obvious. Pharynx faint and smooth.
+Contractile vacuole terminal. Macronucleus in one central body or in
+numerous pieces scattered throughout the cell.  Salt water.
+
+
+Trachelocerca phoenicopterus Cohn '66.  Fig. 30.
+
+Synonyms: _T. sagitta_ Ehr. '40, Stein '59; _T. tenuicollis_
+Quennerstedt '67, Kent '81; _T. minor_ Gruber '87, Shevyakov '96.
+
+The body is extremely elongate and ribbon-like, and this, combined
+with its wonderful power of extension and retraction, makes it one of
+the most curious and interesting of microscopic forms. The anterior
+end is square or cylindrical; the type species has a four-sided
+mouth, but many specimens may be found which have a plain cylindrical
+mouth region. One reason for this may be the fact that the extremity
+gets broken off. In one instance I noticed a very large form with the
+anterior end under some debris, which evidently held it tight, for
+the body of the ciliate was thrashing back and forth and twisting
+itself into knots, etc., like a nematode worm. Finally, the anterior
+end broke off with about one-tenth of the body; the remainder, in an
+hour, had regenerated a new anterior end with long cilia, but with
+no indication of four sides. The small anterior piece was also very
+lively, moving about and eating like the normal animal; its history,
+however; was not followed. This species appears to be variable in
+other ways as well; thus, in some cases the posterior end is rounded
+(cf. Entz '84); in others it is pointed (cf. Kent '81, Cohn '66, et
+al.).
+
+Again, the macronucleus may be a single round body (Entz '84,
+Bütschli '88) or in two parts (Kent '81), or in many parts scattered
+about the body (Gruber). In the Woods Hole forms the tail is
+distinctly pointed and turned back sharply, forming an angle at the
+extremity. The cilia on this angular part are distinctly longer than
+the rest. The function of this posterior part is apparently to anchor
+the animal while it darts here and there upon the tail as a pivot,
+contracting and expanding the while. The body is finely striated
+with longitudinal markings; when contracted there are no transverse
+markings nor annulations. The nucleus is in the form of many
+fragments scattered throughout. Length of large specimen 1.7 mm.
+
+
+[Illustration: Fig. 30.--_Trachelocerca phoenicopterus_.]
+
+
+Genus MESODINIUM Stein '62.
+
+(Maupas '82, '84; Entz '84; Shevyakov '96.)
+
+The main part of the body is globular or conical, with a short,
+platform-like oral region, and a deep annular groove about the
+middle of the body. The oesophagus is rather long, and smooth or
+longitudinally striped. One or more rings of cirri rise in the
+groove. If more than one ring of cirri are present, the anterior set
+usually point forward and lie close to the anterior part of the body.
+The posterior set, on the other hand, cling close to the posterior
+region of the body and give to it a peculiar encapsuled appearance.
+The most characteristic feature is the presence of four short
+tentacle-like processes which can be protracted and retracted from
+the oral region. (Mereschowsky says that the entire anterior half
+is more or less contractile.) The macronucleus is horseshoe-shaped
+or ovoid and is situated in the posterior half of the body. The
+contractile vacuole is also posterior.
+
+Movement consists in rapid swimming, with rotation on its axis, or
+in creeping by means of its anterior cirri, or in sudden jumping, by
+which it apparently clears a distance of 20 times its diameter in one
+bound. Mouth parts may also be used for attachment to foreign bodies.
+The moving periods alternate with quiescent periods, during which the
+organisms with their outstretched and radiating cirri resemble the
+heliozoön _Actinophrys_.
+
+
+Mesodinium cinctum, n. sp.  Fig. 31.
+
+Body spherical to pyriform, constricted near the middle, the
+constriction dividing the body into dissimilar parts. The anterior
+part is broadly pyriform, somewhat plastic and hyaline, with an oral
+extremity which is sometimes hollow, sometimes evaginated and convex.
+Upon this flexible anterior part there are four short but distensible
+tentacles. The posterior part is granular and usually filled with
+food particles; it is well rounded and holds the nucleus and
+contractile vacuole. The entire body is surrounded by a fine cuticle.
+The nucleus is elongate and extends through the greater part of the
+posterior half. The contractile vacuole lies on one side, near the
+girdle. The mouth is on the anterior pole in the tentacle region. The
+motile organs are cirri and cilia, all inserted in the constriction.
+There are two sets of cirri and one of cilia; the latter stand out
+radially from the girdle and are usually in motion. The cirri of
+one set, the anterior, extend forward about twice the length of the
+anterior half; those of the posterior set closely engirdle the lower
+half, reaching not quite to the posterior extremity. These are
+somewhat hyaline and are closely approximated, giving the impression
+of a tight-fitting crenulate casing about the lower half. The cirri
+are sharply pointed, much broader at the base, and the two sets are
+so placed that, looked at from above, they have the appearance of a
+twisted cord. (Fig. 31 b.) Movement erratic; sometimes the animal
+swims steadily forward with mouth in front; again it shoots across
+the field of the microscope, either backward or forward or sideways,
+through the action of its powerful cirri. It is often quiet, usually
+mouth downward, and is held in place by adhesion of the tentacles. In
+this position it looks strikingly like a heliozoön.
+
+Length 35µ; greatest width 30µ. Not uncommon.
+
+The chief features by which this species is distinguished from the
+frequently described _M. pulex_ of Europe are the number of anterior
+cirri and the ring of true cilia in place of the central girdle of
+cirri. The European form is described with four anterior bristles;
+the present form has from 28 to 32. The radial cilia differ decidedly
+from the more powerful cirri and they are not in one plane, so that
+counting is difficult; they are not closely set. The presence of
+tentacles makes these forms of especial theoretical interest,
+especially in the light of the origin of _Suctoria_.
+
+
+[Illustration: Fig. 31.--Side and top views of _Mesodinium cinctum_.]
+
+
+Genus TIARINA R. S. Bergh '79.
+
+(Claparède & Lachmann '58.)
+
+Body subcylindrical, pointed posteriorly, two and one-half times
+as long as broad; encased in covering composed of separate pieces
+arranged in five girdles. The pieces bear processes which rest
+against neighboring pieces of the girdle. Mouth large, anus terminal
+near contractile vacuole. The macronucleus is simple and round. Salt
+water.
+
+
+Tiarina fusus (Cl. & Lach.) emend R. S. Bergh.
+
+Synonyms: _Coleps fusus_ Cl. & Lach. '58; Daday '86; Möbius '88,
+Lauterborn '94; Shevyakov '86.
+
+This form, which resembles _Coleps_ rather closely, was placed as a
+separate genus by R. S. Bergh. The skeletal parts consist of five
+zones of needles composed of an organized substance and embedded in
+the cortical plasm, the last zone coming to a point at the posterior
+end. The needles have lateral processes, which give a latticed
+appearance to the casing. The cilia are long, with a specialized
+crown of still longer ones at the oral end; they arise outside of the
+skeletal elements and do not pass between them, as in _Coleps_.
+
+
+KEY TO MARINE GENERA OF TRACHELINIDÆ.
+
+Diagnostic characters: Body bilateral, or asymmetrical by local
+prolongations; usually compressed or flattened laterally, the left
+side more convex than the right. The essential feature is the
+position and character of the mouth. This is either a long slit
+extending from the anterior end well down the ventral surface, or the
+posterior part only of a ventral furrow remains open as a round or
+elongate mouth some distance from the anterior end. The entire mouth
+region of the body is usually drawn out into an elongate tapering
+proboscis which is generally curved dorsally at the extremity.
+An oesophagus is short or absent altogether; when present it is
+supported by a stiff buccal armature. Cilia are uniform about entire
+body or limited to the flat right side. Food is swallowed.
+
+1. a. Proboscis easily distinguished      2
+      from the main body
+
+   b. Proboscis not marked off from       Genus *_Loxophyllum_
+      main body; body flat;
+      both surfaces striated
+
+2. a. Mouth runs the entire length        Genus _Amphileptus_
+      of proboscis; entire body
+      uniformly ciliated
+
+   b. Mouth runs the entire length        Genus *_Lionotus_
+      of proboscis; body flat; right
+      side only is ciliated
+
+   c. Proboscis much drawn out,           Genus _Dileptus_
+      flexible; mouth at its base
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LOXOPHYLLUM Dujardin '41.
+
+(Duj. '41; Wrzesniowski '69; Quennerstedt '65; '67; Cohn '66; Entz
+'84; Gourret & Roeser '88; Bütschli '88; Shevyakov '96.)
+
+The body is flat and somewhat leaf-shape, flexible, and elastic. The
+anterior end is somewhat proboscis-like and flexible, but is not
+sharply demarcated as in _Lionotus_. The central portion of the body
+is developed into a more or less arched dorsal mass, which usually
+contains the nuclei and contractile vacuoles. As a result of this
+local thickening, the body is surrounded by a thin hyaline margin.
+This, however, may be absent on the right side in some species. The
+mouth reaches from the anterior extremity to a short distance from
+the end, and usually approaches the left edge. An anus is present
+near the posterior end of the dorsal swelling. Trichocysts are
+numerous on the ventral surface, and often on the dorsal surface,
+where they are inclosed in minute papilla-like swellings.
+Cilia-distribution controverted. Maupas and Bütschli hold that
+ventral surface alone is ciliated; others (Kent and Dujardin) that
+cilia are uniformly distributed. The entire body, dorsal and ventral
+surfaces alike, are uniformly striated. The contractile vacuole lies
+posteriorly, on the right side and in the dorsal swelling. In the
+fresh-water form _L. meleagris_, it is connected with a long canal
+whose swellings are frequently taken for additional contractile
+vesicles (Bütschli); in the marine form described below the canal is
+not developed and a series of vacuoles takes its place; these are
+all contractile. The macronucleus may be single, double, quadruple,
+band-formed, or rosette-formed. Movement is steadily progressive and
+peculiarly gliding. Fresh and salt water.
+
+
+Loxophyllum setigerum Quenn. '67.
+
+Synonyms: _Litosolenus armatus_ Stokes '93; _Litosolenus verrucosa_
+Stokes '93.
+
+The body is flattened, irregular in outline, obtusely pointed
+anteriorly, the point being turned to the right; rounded posteriorly.
+The left edge is nearly straight, the right considerably arched with
+a few setæ on the posterior half. Contractile vacuoles are numerous,
+dorsal in position and on the right side. The macronueleus is beaded,
+the several spheres connected.
+
+
+Variety armatum (Cl. & Lach.) Fig. 32.
+
+Under the name _Litosolenus armatus_, Stokes described a form from
+brackish water near New York, which should unquestionably be referred
+to the genus _Loxophyllum_, and I believe to Quennerstedt's species
+_setigerum_. While the latter possesses only a few setæ, the former
+has a number of them, and Stokes described his species as having a
+variable number. For this reason I include the Woods Hole form under
+the tentative name _armatum_, as a variety of Quennerstedt's _L.
+setigerum_. The flat margins are distinctly striated longitudinally,
+and faintly marked radially, on the dorsal surface. Longitudinal
+elevated striæ also run the length of the dorsal hump and upon the
+entire ventral surface. The ventral surface is alone ciliated. Upon
+the edges of the flat border are sharp-pointed, colorless, spine-like
+processes, situated at equal distances around the entire periphery
+except at the anterior end. Each spine is thick at the base and
+tapers to a full point which is curved upward--_i. e._, dorsally
+(fig. 32, a, b). The entire body is plastic and contractile, turning
+its leaf-like edge readily over objects upon which it creeps. The
+cilia are fine and uniform, with a tendency to lengthen in the oral
+region.
+
+Length 100µ; greatest width assumed on contraction 85µ; when normal
+about 50µ.
+
+
+[Illustration: Fig. 32.--_Loxophyllum setigerum_, var. _armatum_. a,
+b, c, ventral, dorsal, and lateral aspects.]
+
+
+Genus LIONOTUS Wrzesniowski '70.
+
+(Incorrectly called _Litonotus_ by many. Entz '84; Gruber '84;
+Bütschli '88; Kent '81; Schewiakoff '89; Shevyakov '96.)
+
+The body is elongate and somewhat lance-shaped, widest at the central
+part and tapering to a point at the anterior end. The posterior end
+may be similarly tapered or rounded. The anterior end frequently
+proboscis-like, flat, and flexible, while the entire body is more or
+less elastic and contractile.  The right side is flattened and alone
+provided with cilia, while the left side of the body proper is
+arched; on the left side of the proboscis is a row of coarse cilia
+resembling an adoral zone, and a row of trichocysts. A long peristome
+stretches down the thin, ventral side of the proboscis, and the mouth
+proper is situated at the junction of the proboscis and body; the
+mouth, as a rule, is invisible. The ciliated right side alone is
+striated in the majority of species. The contractile vacuole may be
+single or multiple, usually in the posterior region of the body and
+dorsal in position. The macronucleus is usually double, rarely single
+or quadruple, but may occasionally break into numerous smaller
+pieces.  Movement, free-swimming or gliding, with especial tendency
+to get under clumps of foreign matter.
+
+Fresh and salt water.
+
+
+Lionotus fasciola Ehr.  Fig. 33.
+
+Synonyms. _Amphileptus fasciola_ Ehr. '38; Dujardin '41; Lachmann
+          '56;  Cohn '66, Diesing '65.
+          _Loxophyllum fasciola_ Claparède & Lachmann '58;
+          Balbiani '61.
+          _Loxophyllum duplostriatum_ Maupas '83. Shevyakov '96.
+
+Body frequently brown or brilliant yellow in color, somewhat sigmoid
+in form with tapering anterior end, the extremity of which is turned
+dorsally. The proboscis is about half the entire length and is not
+sharply marked from the rest of the body but tapers gradually, its
+base being equal to the diameter of the body at its middle point. The
+body is slightly contractile and the posterior end is carried to a
+rounded point, but not into a distinct tail. Unlike the fresh-water
+variety, this one has no hyaline margin nor hyaline caudal region,
+and the contractile vacuole is double or multiple on the dorsal side
+near the posterior end. Cilia are present only on the under (right)
+side, with, however, a row of large cilia marking the course of the
+elongate mouth, upon its left side. The right side is striated, the
+left arched and without markings. The endoplasm is finely granular
+with, however, larger food particles in the process of digestion,
+while specimens are occasionally seen with the natural form
+completely lost through distortion caused by over-large captures (Cf.
+also Wrzesniowski '70, p. XXIII, fig. 32). Movement continuous, slow,
+and gliding; very little tendency to jerking movements. Macronucleus
+double, both parts spherical, and placed in about the center of the
+larger part of the body; closely approximated but not, as Schewiakoff
+described, connected. In conjugation, a large form unites with a
+smaller one, the mouth parts being connected. Details of conjugation
+and macronuclei not made out. Length 200µ to 600µ.
+
+
+[Illustration: Fig. 33.--_Lionotus fasciola_.]
+
+
+KEY TO MARINE GENERA OF CHLAMYDODONTIDÆ.
+
+Diagnostic characters: Form usually ellipsoid, never very elongate.
+Transverse section of body circular or elliptical. The mouth is
+usually some distance from the anterior end and may be in the
+posterior part. Sometimes it is in the center of the ventral
+surface, again on the right side. The oesophagus invariably has
+a well-developed buccal armature, or a smooth peculiarly built
+oesophageal tube. Food particles of large size.
+
+1. Body cylindrical. Cilia about          Genus *_Nassula_
+   entire body
+
+   Body flat                              2
+
+2. a. Without a caudal process            3
+
+   b. With a caudal process               5
+
+3. a. Anterior end angular                4
+      on left side
+
+   b. Anterior end rounded                Genus _Chlamydodon_
+
+4. a. Dorsal striæ and cilia present,     Genus _Orthodon_
+      ventral cilia longer
+
+   b. Dorsal striæ and cilia absent;      Genus *_Chilodon_
+      posterior end not pointed
+
+   c. Dorsal striæ and cilia absent;      Genus _Scaphidiodon_
+      posterior end pointed
+
+5. a. Caudal spine with posterior         6
+      bristle-like cilia
+
+   b. Caudal spine without posterior      Genus _Trochilia_
+      bristle-like cilia;
+      ventral cilia reduced
+
+6. a. With pigment spot on anterior       Genus _Ægyria_
+      angle
+
+   b. Without such pigment spot           Genus _Onychodactylus_
+
+   c. Cilia on right edge only of         Genus *_Dysteria_
+      greatly reduced ventral surface
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus NASSULA Ehr. '33
+
+(Dujardin '41; Stein '67; Cienkowsky '55; Cohn '66; Clap. et Lach.
+'58; Kent '81; Maupas '83; Entz '84; Fabre-Domergue '88; Bütschli
+'88; Shevyakov '96.)
+
+The body is ovoid or cylindrical, with well-rounded ends, and in
+some cases slightly flattened. The mouth is ventral and placed some
+distance from anterior end (1/4 to 1/3 total length). A slight
+depression on the ventral surface marks the mouth region, which is
+further indicated by larger and more powerful cilia. The rest of the
+body is uniformly ciliated. The entire body is marked by clearly
+defined spiral stripes. The mouth is circular and the oesophagus is
+supported by a considerable armature, which usually extends dorsally
+and to the left, rarely to the right. In some cases the structure of
+this armature is indistinct; again it can be clearly seen to consist
+of definite rods (Stäbchen). The anus is probably always terminal.
+Contractile vacuoles are variable in different species. In some cases
+there is but one, which is placed at the posterior end or centrally
+on the ventral side; in others there may be four--two dorsal and
+two ventral. In many cases trichocysts are uniformly distributed.
+Sometimes the body is colorless; again, and more often, it is
+brightly colored with red, blue, brown, or black pigment. The
+macronucleus is globular and central, occasionally band-form and
+with numerous attached micronuclei. Food substance varied, usually
+vegetable matter, see, however, below. Cysts are globular. Movement
+is a steady progression, combined with rolling.
+
+
+Nassula microstoma Cohn '66.  Fig. 34.
+
+Synonyms: _Paramoecium microstomum_ Cl. et Lach. '58, Gourret et
+Roeser '88; _Isotricha microstomum_ Kent '81.
+
+Body subcylindrical, rounded at each extremity, not quite twice as
+long as broad. A slight depression on one surface marks the position
+of the mouth, this depression being indicated by a row of longer
+cilia. The mouth is extremely small and is surrounded by a curious
+buccal armature. This is not made up of bars or rods, as in most
+species of _Nassula_, but appears perfectly smooth and uniform
+except for the considerable swelling at the inner end. The cuticle is
+firm and unyielding and marked by longitudinal and somewhat spiral
+rows of cilia and trichocysts. Under the microscope this is one of
+the most pleasing forms found at Woods Hole. Its color is yellowish
+brown from the presence of brilliant particles of coloring matter
+held in the cortical plasm, and, as it slowly rolls along, these
+particles and the black trichocysts give to the organism a peculiar
+sparkling effect. The macronucleus is almost central; the contractile
+vacuole posterior. The endoplasm appears well filled with food
+bodies, some of which could be distinguished as _Amphidinium_ and
+_Glenodinium_.
+
+Length 55µ; greatest diameter 30µ.
+
+
+[Illustration: Fig. 34.--_Nassula microstoma_.]
+
+
+Genus CHILODON Ehr.
+
+(Dujardin '41; Engelmann '78; Stein '54, '58; Kent '81; Bütschli '88;
+Gruber '83; Cienkowsky '55; Möbius '88; Clap. et Lach '58;
+Wrzesniowksi '65; Shevyakov '96.)
+
+Small forms, greatly flattened dorso-ventrally and almost egg-form in
+outline. The anterior end is bent distinctly to the left and forms a
+characteristic process, which, together with the entire margin of the
+body, is soft and flexible. The posterior end is, as a rule, broadly
+rounded. The ventral surface is finely striate, and this surface
+alone is ciliated. The lines of cilia converge at the mouth, and at
+this region the cilia are somewhat larger and more distinct, thus
+forming a functional adoral zone. The mouth is median and is situated
+in the anterior half of the body. It is surrounded by a well-defined
+armature, composed usually of from 10 to 16 rods. The contractile
+vacuoles are quite varied and from one to many in number, the
+number increasing with the size of the individual. The macronucleus
+is usually single, elliptical in form, and centrally placed;
+one micronucleus. Reddish granular pigment and trichocysts are
+occasionally present.
+
+
+Chilodon cucullulus Müll., sp.  Fig. 35.
+
+Synonyms; _Colpoda cucullus_ O. F. Müller; _Loxodes cucullulus_;
+_Chilodon uncinatus_ Ehr. '58, Perty '52, Dujardin '41; _L. dentatus_
+Duj., etc.
+
+This extremely variable form has received so many different names
+that it hardly pays to enumerate them. It is one of the commonest
+and most widely spread ciliates known, although at Woods Hole I was
+surprised to see it so rarely. It is the type species of the genus
+and needs no further description. The specimens observed at Woods
+Hole had numerous contractile vacuoles and were 42 to 45µ long and
+from 28 to 32µ wide.
+
+
+[Illustration: Fig. 35.--Ventral and dorsal aspects of _Chilodon
+cucullulus_.]
+
+
+Genus DYSTERIA Huxley '57.
+
+(Cl. et Lach. '58; Entz '84; Möbius '88; Shevyakov '96.)
+
+Small forms, firm in outline, and colorless or slightly colored. The
+body is somewhat clam-shaped, flattened, slightly curved or straight
+on the right side, the other more convex. The true ventral side is
+only a narrow strip along the right and anterior edge of the body,
+the apparent ventral side being a fold of the very large dorsal
+surface which comes around ventrally, forming a valved structure
+somewhat analogous to a clam shell. Cilia are limited to the outer
+edge of the small ventral surface, which also bears a peculiar spine
+at the posterior end. Behind this spine are larger cilia. The mouth
+opening lies in the anterior widened portion of the ventral surface
+and is connected with a smooth tubular pharynx. The right half of the
+dorsal side, _i.e._, the apparent dorsal side, is arched and bears
+longitudinal ridges. Two to four contractile vacuoles are placed on
+the ventral side. The macronucleus is usually dorsal, elliptical, and
+cleft, with one micronucleus attached. Fresh and salt water.
+
+
+Dysteria lanceolata Cl. et Lach.  Fig. 36.
+
+Synonym: _Cypridium lanceolatum_ Kent '81.
+
+Outline of the flattened body ovoid; body consists of two valve-like
+portions; the edge of the right valve is nearly straight, that of the
+left valve more or less sinuous; anteriorly it is cut away, obliquely
+and posteriorly it has a deep indentation in which the seizing spine
+rests. The cilia are confined to the ventral surface, here reaching,
+however, from the anterior dorsal extremity to below the posterior
+indentation. Posteriorly the cilia become larger, corresponding to
+the larger cirri of _D. armata_, which are posterior to the spine.
+The mouth lies between the two valves and is surrounded by a long
+and smooth buccal armature which passes downward and backward to
+the left a distance equal to about half the entire body length. The
+macronucleus is situated in the dorsal region in the central part of
+the body. There are two contractile vacuoles, one behind the center
+of the buccal armature, the other near the inner end of this organ.
+Movement is in circles, the animal moving around quite rapidly when
+not attached by its posterior process. It is colorless and measures
+45µ in length by 27µ in width. Claparède & Lachmann and Shevyakov
+describe it as 70µ long.
+
+
+[Illustration: Fig. 36.--_Dysteria lanceolata_.]
+
+
+KEY TO MARINE GENERA OF CHILIFERIDÆ.
+
+Diagnostic characters: Mouth never lies behind the middle of the
+body; the oesophagus is but slightly developed. The undulating
+membranes are placed either on the edge of the mouth or in the
+oesophagus. A peristomial depression leading to the mouth is absent
+or very slightly indicated.
+
+1. Mouth in the anterior half,            Genus *_Frontonia_
+   undulating membrane on left edge
+   only; right edge continued in a
+   long ventral furrow
+
+2. Two undulating membranes; mouth        Genus *_Colpidium_
+   central; no caudal bristles
+
+3. Two undulating membranes; caudal       Genus *_Uronema_
+   bristle
+
+
+Genus FRONTONIA Ehr. (Cl. & Lach. '58?).
+
+(Ehrenberg, subgenus of _Bursaria_ '38; Claparède & Lachmann '58;
+Bütschli '88; Shevyakov '96.)
+
+Form elongate and cylindrical, or often flattened dorso-ventrally,
+with round or pointed ends. It is usually plastic and contractile.
+Cilia are evenly distributed about the body and are similar in
+length. The large, open mouth lies on the anterior half of the
+ventral surface, and is elongate and oval in outline. On its left
+edge is a well-defined membrane which stretches across to the right
+side of the mouth. On the right edge is a small, longitudinally
+striped tract which is free from trichocysts and smooth in
+appearance. This tract is continued posteriorly in a long furrow,
+which in some cases reaches the posterior end of the animal. A few
+rows of cilia in this furrow vibrate differently from the others and
+give the effect of a membrane (Bütschli). The oesophagus is extremely
+short and hard to make out. The body is usually covered uniformly
+with trichocysts, often of considerable size. There are 1 or 2
+vacuoles with long canals radiating throughout the endoplasm. The
+macronucleus is oval and centrally placed. Micronuclei vary from
+one to many. An anal opening is placed at the end of the long
+ventral furrow. The plasm is colorless or green by the presence of
+Zoochlorella, or colored brown or black by pigments. In these cases
+there is a considerable pigment mass on the anterior end. Movement
+is regular, forward, and combined with rotation. Food consists of
+foreign objects, diatoms, other protozoa and the like. Fresh and salt
+water.
+
+
+Frontonia leucas Ehr.  Fig. 37.
+
+Synonyms: _Frontonia vernalis_ Ehr. '38; _Bursaria leucas_ Allman
+'55, Carter '56; _Panophrys leucas_ Duj. '41, Stein '67; _Panophrys
+vernalis_ Dujardin '41, Stein '67; _P. chrysalis_ Duj. '41, Fromentel
+'74; _Cyrtostomum leucas_ Stein '67, Kent '81.
+
+Form ovoid, elongate, occasionally a little flattened
+dorso-ventrally. Mouth in the anterior third of the body. The left
+edge of the mouth carries a distinct undulating membrane; the right
+edge is plain, longitudinally striated and bears cilia. It is
+slightly depressed and the depression is carried posteriorly in the
+form of a shallow furrow which reaches to the posterior end. The
+contractile vacuole is on the left side, the spheroidal nucleus on
+the right side of the furrow. The body is uniformly covered with fine
+cilia, and the periphery is uniformly studded with large trichocysts,
+except along the furrow. Food consists of dinoflagellates and other
+small forms. Color dark brown to black.
+
+Length 330µ; width 200µ.
+
+This form differs considerably from the fresh-water _Frontonia
+leucas_ as described by Schewiakoff '89, especially in the extreme
+length of the peristomial furrow, in the position of the nucleus and
+contractile vacuole, and in the nature of the water canals. These
+in the Woods Hole form are very irregular in size and very much
+branched, not uniform as in Lieberkühn's (see Bütschli) figure of
+_Frontonia leucas_, nor radiating as in Schewiakoff's description.
+This may be the same species as _Frontonia marina_, of Fabre-Domergue
+'91, whose description and figure I have not seen.
+
+
+[Illustration: Fig. 37.--_Frontonia Leucas_.]
+
+
+Genus COLPIDIUM Stein '60
+
+(Bütschli '88; Maupas '83.)
+
+The general form is oval, slightly compressed laterally with the
+dorsal side strongly arched. The ventral side is slightly incurved.
+The anterior end is somewhat smaller than the posterior end, which is
+broadly rounded. The mouth is placed some distance from the anterior
+end in an oral depression and opens into a tubular oesophagus. There
+are usually two undulating membranes which do not extend beyond the
+mouth borders. The right undulating membrane extends down into the
+oesophagus and appears to be attached to the walls of the latter. The
+body stripes in front of the mouth are twisted to the left. The anus
+is terminal and the contractile vacuole may be terminal or situated
+forwards in the dorsal region. The macronucleus is spherical and
+has one  micronucleus attached. Food consists mainly of bacteria.
+Movement rapid, but interrupted.
+
+Fresh and salt water, common in infusions.
+
+
+Colpidium colpoda Ehr., sp.  Fig. 38.
+
+Synonyms: _Colpidium cucullus_ Kent '81; _C. striatus_ Stokes '85;
+_Kolpoda cucullus_ Duj. '41; _Paramoecium colpoda_ Ehr. '38,
+Quennerstedt '67; _Plagyiopyla nasula_ Kent '81, G. & R. '86;
+_Glaucoma pyriformis_ G. & R. '86; _Tillina campyla_ Stokes '85, '88.
+
+The body is oval, somewhat larger posteriorly, and a little
+compressed dorso-ventrally. The anterior end is twisted a little from
+the right to the left (more evident in fresh-water forms), and leans
+somewhat toward the ventral side. Under this portion, on the ventral
+side, lies the mouth in a large depression just above the middle of
+the body. The entire body is covered with uniform and delicate cilia,
+which are placed in longitudinal rows. These rows are almost straight
+on the dorsal side, but bend on the ventral surface, following
+the contour of the twisted anterior portion. The endoplasm is
+finely granular; the oesophagus leading into it is very distinct.
+Schewiakoff ('89) describes two membranes, an inner and an outer;
+Maupas ('83) describes them as right and left. In the present species
+I was able to make out only one. The macronucleus is central,
+spherical in form, and bears a single minute micronucleus. The
+contractile vacuole is posterior and dorsal to the long axis of the
+body. The anus is ventral to this axis and also posterior. Length
+45µ, width 20µ. Common.
+
+This marine variety is much smaller than the fresh-water form and the
+form differs in a number of respects, viz, in the anterior torsion
+and in the structure of the mouth. These may be, however, only
+individual variations of a widely spread species, and I believe it is
+perfectly safe to describe this as _Colpidium colpoda_.
+
+
+[Illustration: Fig. 38.--_Colpidium colpoda_.]
+
+
+Genus URONEMA Duj. '41.
+
+(Quennerstedt '69; Cohn '66; Kent '81; Bütschli '81; Schewiakoff '89;
+Shevyakov '96.)
+
+Minute forms; colorless and constant in body form. The form is oval,
+slightly compressed on the ventral side, while the dorsal side is
+distinctly arched. The membrane is distinctly marked by rather widely
+separated striæ. These occasionally have a spiral course about the
+body; in all cases they can be easily counted. The mouth is large
+and placed near the center of the ventral surface. It is sometimes
+approached by a very shallow depression or peristome from the
+anterior end, and marked by two rows of cilia. An undulating membrane
+extends down the mouth. Oesophagus absent. A long, stiff bristle
+extends outwards from the posterior end. The contractile vacuole is
+terminal or subterminal and near the anal opening. The macronucleus
+is spherical, centrally placed, and with one micronucleus closely
+applied. Movement is rapid and usual forwards in a straight line,
+often found resting, however, with outstretched cilia in contact with
+some foreign body. Food mainly bacteria. Fresh and saltwater, usually
+in decomposing vegetable substances.
+
+
+Uronema marina Duj.  Fig. 39.
+
+Synonyms: _Enchelys triquetra_ Dujardin; _E. corrugata_ Duj.;
+_Cryptochilum griseolum_ Maupas '83; _Philaster digitiformis_
+Fabre-Domergue '85.
+
+Small animals with ellipsoidal form and about twice as long as
+broad. The mouth lies in the upper half of the body and bears a
+well-developed undulating membrane upon its left edge. The membrane
+is longitudinally striped and covered with long and vibratile cilia.
+The right edge of the mouth bears cilia which are about the same in
+size as the body cilia, but are more closely inserted (Schewiakoff).
+The most characteristic feature is the long caudal bristle, which
+is extremely delicate and about two-thirds the length of the body.
+Schewiakoff thinks this bristle has a sensory function. I could not
+make this out, for although other protozoa ran against this bristle,
+often bending it well over to one side, the animal showed no sign
+of irritability but lay quiescent. A spherical macronucleus with
+attached micronucleus lies in the center of the body. The contractile
+vacuole is posterior in front of the bristle. The macronucleus was
+found to be double, as though just divided, in a large percentage of
+cases. This may be a precocious division of the nucleus long before
+signs of the body division are evident. Such a phenomenon, however,
+is rare, the macronucleus usually dividing at a late stage of cell
+division. Length 30 to 50µ; width 15 to 20µ. Common in decomposing
+algæ.
+
+
+[Illustration: FIG. 39.--_Uronema marina_.]
+
+
+KEY TO MARINE GENERA OF PLEURONEMIDÆ.
+
+Diagnostic characters: The mouth is at the end of a long peristome
+running along the ventral side; the body is dorso-ventrally or
+laterally compressed. The entire left edge of the peristome is
+provided with an undulating membrane which occasionally runs around
+the posterior end of the peristome to form a "pocket" leading to
+the mouth. The right edge of the peristome is provided with a
+less-developed membrane. There may or may not be a well-developed
+pharynx.
+
+Body small; not produced into             Genus *_Pleuronema_
+ neck-like elongation
+
+Body medium-sized; anterior end           Genus *_Lembus_
+produced into neck-like elongation
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PLEURONEMA Dujardin '41.
+
+(Perty '52; Clap. & Lach. '58; Stein '59, vol. I; Quennerstedt '67;
+Kent '81; Bütschli '88; Schewiakoff '89; Shevyakov '96.)
+
+Small to medium-sized ciliates, with an unchanging form. They are
+somewhat lens-shape and laterally compressed, the two surfaces
+about equally arched. The ventral surface is nearly straight or
+but slightly arched; the dorsal is quite convex.  The anterior and
+posterior extremities are equally rounded.  The peristome begins as
+a small depression, but becomes larger until it takes in nearly all
+of the ventral surface. The depression becomes much deeper at about
+the center of the body, and is especially marked on the left side of
+the peristome. In this deeper portion is the mouth, with an almost
+imperceptible oesophagus. Upon the left edge of the peristome is a
+high, undulating membrane, sail-like in appearance when extended.
+This may stretch around the posterior edge of the peristome and upon
+the right aide, thus forming a pocket by means of which the food
+particles are directed into the mouth. The rest of the right edge
+of the peristome is occupied by closely approximated powerful cilia
+(Bütschli) or a second undulating membrane (Stein). The body cilia
+are relatively long. Trichocysts and caudal bristles may be present.
+The contractile vacuole is subterminal and dorsal; it is questionable
+whether there are canals leading to it. A round macronucleus with
+one micronucleus is in the anterior half of the body. The anus is
+terminal. Food is chiefly bacteria. Movement combines springing with
+swimming and rotation. Fresh and salt water.
+
+
+Pleuronema chrysalis Ehr., sp.  Fig. 40.
+
+Synonyms: _Pleuronema crassa_ Dujardin '41; _P. marina_ Duj. '41;
+Fabre-Domergue '85; _P. coronata_ Kent '81; _Paramoecium chrysalis_
+Ehr. '38; _Lembadion orale_ G. & R. '88; _Histiobalantium agile_
+Stokes '85, '88.
+
+The body is ovoid, slightly flattened, rounded at both ends, the
+anterior end sharper than the posterior. The ventral surface is
+almost entirely taken up by a peristome which extends from the
+anterior end posteriorly three-quarters of the body length. The
+posterior end of the peristome is straight, the left curved,
+following the depressed portion. The body is covered with fine cilia
+in longitudinal lines, except on the peristome. The mouth is small
+and situated in the hollow of the peristome near the left border. On
+the left peristome edge is a large undulating membrane. It begins
+near the anterior end of the body and increases in height posteriorly
+following the peristome edge around on the right side. This posterior
+bend of the membrane causes the appearance of a full sail, so
+often seen. It can be entirely withdrawn and folded together in
+the peristome. On the right edge of the peristome are large,
+powerful cilia. The contractile vacuole is central and dorsal; the
+macronucleus is in the anterior half of the body, with one attached
+micronucleus. Food consists of bacteria. Not very common. Fresh
+and salt water. It often remains quiet, with membrane and cilia
+outstretched, as though dead, but suddenly gives a spring and is
+gone.
+
+
+[Illustration: Fig. 40.--_Pleuronema chrysalis_.]
+
+
+Pleuronema setigera, n. sp.  Fig. 41.
+
+Body colorless, elongate, and with the general form of a cucumber,
+the posterior end being somewhat pointed. The mouth and relatively
+small peristome are situated in the lower third of the body. The
+peristome begins as a shallow furrow at the center of the ventral
+surface and dips sharply into the buccal depression, which is deep
+and turned toward the posterior end. The left edge of the peristome
+bears a high undulating membrane, which extends anteriorly only
+as far as the center of the body; posteriorly it passes around to
+the right edge of the peristome, thus forming the characteristic
+membranous pocket. Inside the oral depression is a second undulating
+membrane, running down to the mouth. This is small and without an
+oesophagus. The body is clothed with long setose cilia which are
+frequently fully outstretched when the animal is resting, a slight
+tremor of the large membrane alone indicating vitality. Posteriorly
+these appendages are drawn out into long filiform setæ, the number
+varying in different individuals from three to nine or ten. These
+are extremely fine and difficult to see without a high power (_e.g._
+1/12 oil) and careful focussing of the substage condensor. Like _P.
+chrysalis_, the resting periods are terminated by sudden springs,
+otherwise the movements are steady and forward. The macronucleus is
+central, and the contractile vacuole posterior and terminal. Length
+45µ to 50µ; greatest diameter 17µ. In decaying algæ.
+
+It was this form, I believe, that Peck '95 described as a "ciliate."
+
+
+[Illustration: Fig. 41.--_Pleuronema setigera_.]
+
+
+Genus LEMBUS Cohn '66.
+
+(Cohn '66; Quennerstedt '69; Kent '81; Fabre-Domergue '85; Gourret &
+Roeser '88; Bütschli '88; Shevyakov '96.)
+
+Free-swimming animals of elongate form, more or less elastic, and
+flexible, bending readily to avoid obstacles, etc. The anterior half
+is usually drawn out into a slightly curved neck-like portion. The
+peristome is a small groove leading from the anterior end to the
+mouth about midway down the ventral side of the body. Bütschli,
+following Quennerstedt, describes an undulating membrane on each side
+of the peristome groove. Other observers, however, usually describe
+but one, the left, which is clearly defined and stretches out some
+distance from the body, while the right border is described as having
+smaller but very active cilia. The general body surface is clothed
+with fine, uniform cilia, and body striæ are usually absent. One
+or more caudal bristles may be present. The contractile vacuole is
+posterior and terminal, and may be multiple. The macronucleus is
+spherical and perhaps double (Kent). Food is chiefly bacteria, and
+the animals are frequently found with the anterior end embedded in
+zoogloea masses. Salt water, usually in infusions.
+
+
+Lembus infusionum, n. sp. Fig. 42.
+
+The body is elongate, lancet-shaped, with a tapering anterior
+extremity. The dorsal outline is concave through the bending of the
+anterior end, while the ventral outline presents an even, convex
+curve. The mouth lies slightly above the center of the body and marks
+the posterior limit of the ventral peristomial groove, which curves
+slightly from the anterior extremity. Each side of this groove bears
+an undulating membrane, the left being much larger and conspicuously
+striated. The general form of this left membrane is triangular,
+the widest part is anterior, the narrowest at the mouth. The
+right membrane is similar in form, but smaller and more active.
+The endoplasm is colorless and finely granular, not regionally
+differentiated. The ectoplasm consists of a relatively thick cortical
+plasm specially noticeable in the posterior half of the body and
+a delicate cuticle which bears almost imperceptible longitudinal
+markings--the insertion points of the fine cilia. The body is covered
+with uniform cilia except at the anterior extremity. Here they are
+much larger and bristle-like. I was unable to find any cilia in the
+peristome. One long caudal bristle, one-quarter of the length of the
+body, trails out behind. The macronucleus is spheroidal and placed
+near the center of the body; a conspicuous micronucleus lies near it.
+A row of contractile vacuoles extends from the posterior end. I have
+seen as many as six of nearly equal size and one or two smaller ones.
+The intervals of contraction are quite long. Length 70 to 75µ;
+greatest diameter 10 to 12µ.
+
+_L. infusionum_ resembles _L. elongatus_ in its general form and in
+its mode of life, for it excavates a retreat in zoogloea masses and
+lies there for considerable periods perfectly quiet. It differs
+from _L. elongatus_ and from _L. velifer_ (probably the same as _L.
+elongatus_ of Claparède & Lachmann) in the presence of the caudal
+bristle, in the absence of annular markings, number of contractile
+vacuoles, and in the slightly smaller size. It resembles _Lembus
+verminus_ (Müller) as described by Kent (_Proboscella vermina_), and
+_L. intermedius_ as described by Gourret & Roeser (_Lembus verminus_
+syn.)in the absence of annular markings and in the presence of a
+caudal bristle. It differs from the former, however, in the absence
+of a tentacle-like process, and from both in the absence of a double
+nucleus and in the presence of many vacuoles. These features are so
+characteristic of all the specimens examined that I have concluded,
+somewhat reluctantly, to give it a specific name. It is common in old
+infusions of algæ, especially after decomposition is well advanced.
+Its food consists of bacteria.
+
+
+[Illustration: Fig. 42.--_Lembus infusionum_.]
+
+
+Lembus pusillus Quennerstedt 1869.  Fig. 43.
+
+Synonym: _L. subulatus_ Kent 81.
+
+This species is much smaller than the preceding, and might easily
+be mistaken for _Uronema marina_. It is subcylindrical in form, the
+anterior end bluntly pointed, the posterior end rounded. The oral
+apparatus is quite different from _Uronema_. The mouth, as in the
+preceding species, is at the end of a long peristomial groove
+extending from the anterior end to the middle of the body. The edges
+of the peristome bear undulating membranes as in _L. infusionum_.
+Like the latter, there is one caudal bristle, but unlike it there is
+only one posterior contractile vacuole, while the endoplasm is filled
+with large granules or food balls. The cuticle is distinctly striated
+with longitudinal markings, and the cilia are uniform in length.
+
+Habitat similar to that of _L. infusionum_, in zoogloea masses.
+Length 26 to 30µ; diameter 7 to 8µ.
+
+Although Quennerstedt's description of _L. pusillus_ makes no mention
+of a caudal bristle, the size and other characters are so closely
+similar that I hesitate to make a new species. The bristle is
+extremely delicate, scarcely thicker than a cilium, and easily
+overlooked, yet with proper focussing of the condenser I found it on
+every specimen examined.
+
+
+[Illustration: Fig. 43.--_Lembus pusillus_.]
+
+
+KEY TO MARINE GENERA OF OPALINIDÆ.
+
+Diagnostic characters: The form is oval, and the body may be short or
+drawn out to resemble a worm. They are characterized mainly by the
+absence of mouth and pharynx.
+
+Anterior end not pointed; body            Genus *_Anoplophrya_
+cylindrical; tapering
+
+Anterior end pointed; body elongate;      Genus _Opalinopsis_
+cylindrical; tapering
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus ANOPLOPHRYA Stein '60.
+
+(Stein '60; Claparède '60; Leidy '77; Vejdovsky '79; Kent '81;
+Balbiani '85; Bütschli '88; Shevyakov '96.)
+
+The general form is elongate, cylindrical or slightly flattened, with
+rounded ends, the posterior end tapering. The body is striated with
+clearly defined, often depressed lines, which run longitudinally and
+sometimes spirally. The contractile vacuoles are usually placed in
+rows upon the edges. The macronucleus is almost always long and
+band-formed, rarely oval, and generally extending through the entire
+length of the body. Micronuclei have been made out in one case.
+Reproduction is effected by simple cross division or by budding at
+the posterior end, and is frequently combined with chain formation.
+The main characteristic is the entire absence of mouth and
+oesophagus, the animals being parasitic in the digestive tract of
+various annelids. Parasites, salt-water forms.
+
+
+Anoplophrya branchiarum. Stein '52.  Fig. 44.
+
+_A. circulans_ Balbiani.
+
+The body is cylindrical to pyriform, in the latter case broadened
+anteriorly. Cuticle distinctly marked by longitudinal striations
+which take the form of depressions and give to the body a
+characteristic melon shape. The endoplasm contains a number of large
+refringent granules--probably body products. The nucleus is elongate,
+somewhat curved, and coarsely granular. A micronucleus lies in the
+concavity. The cilia are long, inserted rather widely apart along
+the longitudinal markings. The contractile vacuole is single and
+is located at the pointed end, which is directed backwards during
+locomotion. One specimen found free swimming among some algæ.
+
+Length 104µ; greatest diameter 36µ.
+
+I was much surprised to find this form swimming about freely in the
+water; its mouthless condition showed it to belong to the family of
+parasites, the _Opalinidæ_. As the name indicates, however, this
+species is an ectoparasite upon the gills, and Stein gave the name
+_branchiarum_ to a fresh-water form parasitic upon _Gammarus pulex_.
+The Woods Hole form is so strikingly similar to the figure of _G.
+branchiarum_ that, although the name was given to a fresh-water form,
+it obviously applies to this marine variety. One important difference
+is the presence of only one contractile vacuole in the marine form.
+
+
+[Illustration: Fig. 44.--_Anoplophrya branchiarum_.]
+
+
+KEY TO FAMILIES OF HETEROTRICHIDA.
+
+Cilia cover the body                      1
+
+Cilia reduced to certain                  2
+localized areas
+
+1. _Polytrichina_.
+
+   a. The mouth terminates a long         Family _Plagiotomidæ_
+      peristomial furrow having an
+      adoral zone along the entire
+      left edge
+
+   b. Peristomial area a broad            Family _Bursaridæ_
+      triangular area ending in mouth
+
+   c. Peristomial depression short;       Family _Stentoridæ_
+      limited to the anterior end; its
+      plane at right angles to the
+      long axis of body; surface of
+      peristome striated and ciliated;
+      no undulating membranes
+
+2. _Oligotrichina_.
+
+   a. Peristome without cilia; cilia      Family _Halteriidæ_
+      limited to one or more girdles
+      about body
+
+      One marine genus                    *_Strombidium_
+
+   b. Thecate forms; the body is          Family _Tintinnidæ_
+      attached by a stalk to the cup;
+      within the adoral zone is a ring
+      of cilia.
+
+   c. The peristomial depression is       Family _Ophryoscolecidæ_
+      deep and funnel-like; cuticle
+      thick, with posterior spine-like
+      processes.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO THE MARINE GENERA OF PLAGIOTOMIDÆ.
+
+Diagnostic characters: The peristome is a narrow furrow which begins,
+as a rule, close to the anterior end and runs backward along the
+ventral side, to the mouth, which is usually placed between the
+middle of the body and the posterior end. A well-developed adoral
+zone stretches along the left side of the peristome, and is usually
+straight.
+
+1. Body cylindrical; size medium;         Genus _Metopus_
+   peristome long and turns sharply
+   to the left at the extremity
+
+2. No torsion in the peristome;           Genus _Blepharisma_
+   undulating membrane is confined
+   to the posterior part of peristome
+
+3. No peristomial torsion;                Genus _Spirostomum_
+   body highly contractile;
+   no undulating membrane
+
+
+KEY TO THE MARINE GENERA OF BURSARIDÆ.
+
+Diagnostic characters: The body is usually short and pocket-like, but
+may be elongate. The chief characteristic is the peristome, which is
+not a furrow, but a broad triangular area deeply insunk and ending in
+a point at the mouth. The adoral zone is usually confined to the left
+peristome edge, or it may cross over to the right anterior edge.
+
+1. The anterior half of the body          Genus _Balantidium_
+   tapers to nearly a point in front;
+   the peristome is narrowest at the
+   apex; the mouth is the entire
+   peristome base.
+
+2. The anterior end does not taper;       Genus *_Condylostoma_
+   the peristome is widest at the end
+   of the body; the mouth is clearly
+   defined.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus CONDYLOSTOMA (KONDYLOSTOMA Bory de St. Vincent 1824) Dujardin
+'41
+
+(Dujardin '41; Claparède & Lachmann '58; Stein '59, '67; Cohn '66;
+Quennerstedt '67; Wrzesniowski '70; Bütschli '76, '88; Kent '81;
+Maupas '83; Shevyakov '96.)
+
+Colorless and more or less flexible animals of medium size. The
+general form is elongate and cylindrical or somewhat smaller
+anteriorly. The posterior end is broadly rounded, the anterior end
+somewhat truncate and oblique. The peristome is broad and triangular,
+the base of the triangle being the entire anterior end of the body.
+The entire length of the peristome is one-fourth or less of the body
+length. The mouth is large and placed at the apex of the peristomial
+triangle and opens into a comparatively small oesophagus. The right
+edge of the peristome is lamellate and bears a clearly defined
+undulating membrane. The adoral zone is well developed upon the left
+edge of the peristome, from which it passes around anteriorly to the
+right edge. The surface of the peristome is free from cilia, but
+the rest of the body is uniformly coated with small active cilia.
+Contractile vacuoles are not safely determined. Bütschli thinks
+there is probably one terminal vacuole, but some observers deny this
+(_e.g._ Maupas). Others describe them on the dorsal side of the
+posterior end (Quennerstedt). The macronucleus is long and beaded and
+placed upon the right side. Micronuclei are numerous and scattered
+along the macronucleus. The anus is terminal and dorsal. Food
+consists of large and small particles. Movement rapid, free swimming,
+alternating with resting periods; in some cases an undulating or
+wriggling movement is seen, showing clearly the flexibility of the
+body. Fresh and salt water.
+
+
+Condylostoma patens Müller.  Fig. 45.
+
+The body is elongate, somewhat sac-like, five or six times as long
+as broad, plastic, and frequently contains brightly colored food
+granules. The triangular peristome takes up the greater part of the
+anterior end, and the mouth is situated at the sharper angle of the
+triangle, about one-fourth of the total length from the anterior end.
+The cuticle is longitudinally striated, the lines having a slightly
+spiral course. They are not closely set, and fine cilia are thickly
+inserted along their edges. The endoplasm is granular and viscous.
+The motile organs consist of an adoral zone of membranelles, which
+stretch along the left edge of the peristome and the front edge of
+the body. The right edge of the peristome supports an undulating
+membrane. The nucleus is moniliform and extends the full length of
+the left side; a number of micronuclei are distributed along its
+course (Maupas).
+
+Length 400µ; diameter at widest part 105µ. Maupas gives the length
+from 305µ to 495µ; and Stein 376µ to 564µ. Very common.
+
+For a more extended account of the structures, see the excellent
+description by Maupas '83.
+
+
+[Illustration: Fig. 45.--_Condylostoma patens_.]
+
+
+KEY TO THE MARINE GENERA OF STENTORIDÆ.
+
+Diagnostic characters: The peristome is relatively short and limited
+to the front end of the animal, so that its plane is nearly at right
+angles to that of the longitudinal axis of the body. The adoral zone
+of cilia either passes entirely around the peristome edge or ends at
+the right-hand edge. The surface of the peristome is spirally
+striated and provided with cilia. Undulating membranes are absent.
+
+1. Peristome circular in outline;         Genus _Stentor_
+   limited to the anterior end
+
+2. The peristome is drawn out into two    Genus _Folliculina_
+   wing-like processes; tube-dwelling
+
+
+Genus STROMBIDIUM Cl. & Lach. '58.
+
+(Stein '67; Bütschli '73; Fromentel '74; Kent '81; Gruber '84; Entz
+'84; Maupas '83. Bütschli '88.)
+
+Small, colorless (except for ingested food) animals with
+characteristic springing movements. The form is usually constant, but
+in some cases may be plastic like _Astasia_; it is usually globular
+or conical, the posterior end being more or less pointed, the
+anterior end broadest. The latter is surrounded by a complete circle
+of the adoral zone, the oral end of which passes into a peristomial
+depression which extends deep into the middle of the body. The mouth,
+with a very small oesophagus, lies at the bottom of the inturned
+peristome. The region surrounded by the adoral zone is frequently
+drawn out into an anterior process, occasionally bearing a pigment
+mass. The ventral surface in some cases bears cilia, which may be
+distributed or restricted to a row of large cilia. Trichocysts are
+usually present and may be widely spread, limited to the posterior
+region, or arranged in a girdle about the middle. The contractile
+vacuole is simple, and posterior in position. The macronucleus
+is spherical and usually central in position. Movement is rapid
+swimming, combined with resting and floating periods, the latter
+usually terminated by a sudden leap.
+
+Fresh and salt water; more common in the latter.
+
+
+Strombidium caudatum Fromentel '74.  Fig. 46, a, b, c.
+
+Fromentel described a fresh-water form of this genus with a caudal
+appendage. The body is pyriform, broadly truncate on the anterior
+end, in the middle of which rises a papilliform process (Schnabel).
+On this process is a heap of pigment granules, which, however, are
+not constant. A ring of long cirri surround the anterior end and pass
+into the peristome, and from the left edge of this line of cirri a
+large adoral zone continues down to the mouth. The peristome is
+elongate and sac-form, and the mouth lies at the posterior extremity.
+With the exception of a caudal filament there are no other motile
+organs; this is about half as long as the body, structureless,
+hyaline, and sharply pointed. It splits up into a bundle of fine
+fibers upon treatment with caustic potash (c). The cirri emerge from
+minute hollows in the edge of the anterior border. The cortical
+plasm contains peculiar rod-like bodies, which look more like lines
+or markings than like rods or trichocysts. The nucleus is large,
+spherical, and placed in the center of the body. The contractile
+vacuole is posterior.
+
+Length without appendage is about 35µ; greatest diameter 15 to 18µ.
+In decaying vegetable matter. Common.
+
+
+[Illustration: Fig. 46.--_Strombidium caudatum_.]
+
+
+Although Fromentel's species is incompletely described, it is very
+evident that the organism corresponds fairly well with the Woods Hole
+variety. His was a fresh-water type; this is marine, but the caudal
+filament and the contractile vacuole are similar. Certainly in this
+case the organism can not be regarded as a Vorticella broken off its
+stalk, as Kent '81 suspected. The anterior process with its pigment
+spot; the cirri, the spherical nucleus, the position of the vacuole,
+etc., are all opposed to such an interpretation which Kent applied to
+the original species. Neither can it be a Tintinnoid. I place it
+provisionally as _S. caudatum_.
+
+
+KEY TO THE MARINE GENERA OF TINTINNIDÆ.
+
+Diagnostic characters: Body attached by a stalk to a cup. Inside the
+zone of membranelles is a ring of cilia (par-oral).
+
+1. The test is gelatinous and more or     Genus _Tintinnidium_
+   less covered by foreign particles
+
+2. The test is chitinous and clear.       Genus _Tintinnus_
+   No foreign particles.
+
+3. The test is chitinous; covered by      Genus *_Tintinnopsis_
+   foreign particles, growth rings
+   frequent
+
+4. The test is chitinous, often           Genus _Codonella_
+   covered by foreign particles.
+   The test is marked by discoid,
+   circular, or hexagonal spots.
+
+5. The test is perforated by pores        Genus _Dictyocysta_
+   of circular or hexagonal form.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus TINTINNOPSIS Stein '67.
+
+(Stein '67; Kent '81; Daday '87; Bütschli '88.)
+
+Medium-sized ciliates, inclosed in a chitinous lorica with embedded
+sand crystals. The form of the house, or lorica, varies greatly.
+In some cases the mouth opening is wide, giving the lorica a bell
+form; it may be long and tubular, short and spherical, or variously
+indented. The animal is attached, as in the closely allied genus
+_Tintinnus_, by a peduncle to the bottom of the lorica. The anterior
+end of the animal is inclosed by two complete circles of cilia;
+one, the outer, forming the adoral zone, is composed of thick
+tentacle-like membranelles, the other consists of shorter cilia
+within the adoral zone. The mouth leads into a curved oesophagus
+containing rows of downward-directed cilia (Daday). The entire body
+is covered with cilia, but as the lorica is always opaque these can
+be made out only when the animal is induced to leave the house. The
+only difference between this genus and _Tintinnus_ is the covering
+of foreign bodies--usually sand crystals. Movement is rapid and
+restless, and peculiarly vibratory, owing to the apparent awkwardness
+in moving the house.  Salt water.
+
+
+Tintinnopsis beroidea Stein, var. plagiostoma Daday.  Fig. 47.
+
+Synonym: _Codonella beroidea_ Entz '84.
+
+The shell is colorless, thimble-shaped, with a broadly rounded
+posterior end. The body is cylindrical. The internal organs were not
+observed. Membranelles 24 in number. Length 50µ; greatest diameter
+40µ.
+
+
+[Illustration: Fig. 47.--_Tintinnopsis beroidea_.]
+
+
+Var. compressa Daday '87.
+
+The posterior end of the shell is pointed, the lower third of the
+shell is swollen, the upper third is uniform in diameter and without
+oral inflation or depression. Nucleus not seen.
+
+Length 70µ; greatest diameter 48µ.
+
+
+Tintinnopsis davidoffi Daday.  Fig. 48.
+
+The shell is large, elongated, and provided with a considerable
+spine. The chitin of the shell is covered with silicious particles of
+diverse size. The internal structures were not observed.
+
+Length of shell and spine 230µ; diameter of the oral aperture 54µ.
+
+
+[Illustration: Fig. 48.--_Tintinnopsis davidoffi_.]
+
+
+The variations of these species are considerable, and as the internal
+structures, such as the nucleus, are essential in fixing their
+systematic position, I place them as above, provisionally, and until
+further observations can be made.
+
+
+KEY TO FAMILIES OF HYPOTRICHIDA.
+
+a. Peristome indistinct; cilia on         Family _Peritromidæ_
+   ventral surface uniform and not        One genus, *_Peritromus_
+   differentiated into cirri
+
+b. Peristome more or less indistinct;     Family _Oxytrichidæ_
+   cilia reduced to a few rows on the
+   ventral surface; anal and frontal
+   cirri present
+
+c. Cilia entirely reduced; frontal        Family _Euplotidæ_
+   and anal cirri present or reduced;
+   macronucleus band-formed or spherical
+
+d. Peristome reduced to left edge and     Family _Aspidiscidæ_
+   does not reach over the anterior       One genus, *_Aspidisca_
+   margin
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PERITROMUS Stein '62.
+
+(Stein '62, '67; Maupas '83.)
+
+The body is flat, colorless or tinged with yellow, and contractile.
+It is elliptical in outline, with broadly rounded ends; in some
+cases the left edge is slightly incurved, the right edge convex.
+The ventral surface is flat, the dorsal surface is arched in the
+middle region of the body. The edges being flat are somewhat more
+transparent than the remainder of the body. The ventral surface is
+striated by longitudinal straight or slightly curved lines, the
+dorsal surface is smooth and without cilia. (Maupas describes
+bristles on the back, but this is not corroborated.) The adoral zone
+is fairly well developed, but not distinctly marked off from the
+remaining ventral surface. It begins on the right side and extends
+entirely around the frontal margin and down the left side below the
+middle of the body, where it turns suddenly to the right, entering
+the slightly insunk peristome. The mouth leads into a short,
+indistinct oesophagus. One contractile vacuole is situated in the
+dorsal swelling at the posterior end of the animal. Macronucleus
+double, one in each side of the dorsal swelling. Movement is slow
+and creeping, with a peculiar method of contracting the more hyaline
+edge, which may turn upward or around a foreign object.
+
+Fresh (?) and salt water.
+
+
+Peritromus emmæ Stein.  Fig. 49.
+
+With the characters of the genus.
+
+
+[Illustration: Fig. 49.--_Peritromus emmæ_, ventral and lateral
+aspects.]
+
+
+KEY TO THE MARINE GENERA OF OXYTRICHIDÆ.
+
+Diagnostic characters: The peristome is not always marked off from
+the frontal area. In the most primitive forms the cilia on the
+ventral surface are similar to those of the preceding family
+(_Peritromidæ_). Usually some of the anterior and some of the
+posterior cilia are fused into cirri, distinguished as the frontal
+and anal cirri, respectively. In the majority of forms all of the
+cilia are thus differentiated; strong marginal cirri are formed in
+perfect rows, and ventral cirri in imperfect rows. In addition to the
+adoral zone there is an undulating membrane on the right side of the
+peristome, and in some cases a row of cilia between the membrane
+and the adoral zone. These are the par-oral cilia and they form the
+par-oral zone.
+
+1. The posterior end is pointed or        2
+   tail-like
+
+   The posterior end is rounded;          5
+   not tail-like
+
+2. The front end is pointed               3
+
+   The front end is rounded               4
+
+3. Frontal and anal cirri absent;         Genus _Stichotricha_
+   often tube-forming
+
+   Eight frontal and 3 caudal cirri;      Genus _Gonostomum_
+   not tubiculous
+
+4. Anal cirri present; with or            Genus *_Epiclintes_
+   without short lateral bristles
+
+   Anal cirri absent; no bristles         Genus _Uroleptus_
+
+5. With frontal cirri                     6
+
+   No frontal cirri; 2 to 3 rows of       Genus _Holosticha_
+   ventral cirri; anal cirri small
+
+6. Right margin of peristome straight     Genus _Oxytricha_
+   as far as the anterior end; 5 rows
+   ventral cirri; 5 anal cirri
+
+   Right margin of peristome curved       7
+
+7. Five rows or less of ventral cirri     8
+
+   More than 5 rows of ventral cirri      Genus _Urostyla_
+
+8. Membranelles normal; 5-10 anal         Genus *_Amphisia_
+   cirri; no caudal cirri
+
+   Membranelles normal; 5 to 10 anal      Genus _Stylonychia_
+   cirri; 3 caudal cirri
+
+   Membranelles very large and            Genus _Actinotricha_
+   powerful; adoral zone not
+   continued to mouth; 5 anal cirri
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EPICLINTES Stein '62.
+
+(Stein '62, '64, '67; Mereschowsky '79; Gruber '87; Bütschli '88.)
+
+Very active, contractile, colorless forms of rather small size. In
+the fully expanded condition the body is oval and long, with its
+greatest width in the center or at the front half of the body. The
+posterior end is always drawn out into a relatively long tail, which
+is extremely elastic. The peristome is short and stretches around the
+front end of the animal. In the frontal region are from one to three
+rows of cirri. The ventral surface is covered with longitudinal rows
+of cilia, the number of rows being in dispute (6 to 7 according to
+Stein; 9 according to Mereschowsky and Rees) Some of these cilia
+project from the lateral edges and from the posterior end, where
+they are slightly elongated. The anus is dorsal and placed at the
+beginning of the posterior process. Macronucleus probably double.
+Movement is rapid and restless, the tail process contracting to jerk
+the body backward. Salt water.
+
+
+Epiclintes radiosa Quenn.  Fig. 50.
+
+Synonym: _Metra radiosa_ Quenn.
+
+The body is elongate, slightly narrowed anteriorly, and drawn out
+posteriorly into a long, retractile, tail-like portion. Five large
+cirri extend outward from the anterior extremity. The caudal portion
+may be extended to a distance equal to twice the length of the body
+or contracted to half the length. The peculiar nervousness of this
+form made it extremely difficult to study, and the oral region was
+imperfectly made out. The anterior cirri appear to line the upper
+left border of the peristome, which is marked by a row of large
+cilia. The peristome begins upon the right side of the anterior end
+and passes backward and to the left, narrowing at this point. The
+mouth is very small and difficult to see. It is apt to stay in
+one locality under zoogloea, switching back and forth with great
+vivacity, or hanging on by the posterior cilia while the anterior
+end stretches out in the surrounding medium. Nucleus and contractile
+vacuole were not observed. Length 45µ.
+
+
+[Illustration: Fig. 50.--_Epiclintes radiosa_.]
+
+
+Genus AMPHISIA Sterki '78.
+
+(Sterki '78; Kent '81; Bütschli '88.)
+
+The body is plastic and soft, colorless or slightly tinged with
+yellow or red. In form it is oval or elongate, the posterior end
+is rounded and slightly reduced in diameter, but does not form a
+distinct tail. The anterior end is also rounded and similarly reduced
+in width. There are two rows of marginal cirri (_Randcirren_), which
+may be placed some distance from the edge, and two or three rows of
+ventral cirri between them. There are from 3 to 5 frontal cirri of
+larger size than those of the ventral rows, and from 5 to 10 anal
+cirri. (The genus _Holosticha_ is similar in all respects save
+the presence of frontal cirri.) The macronucleus is double; the
+contractile vacuole is central and on the left side. The peristome
+is long and rather narrow and carries an undulating membrane on its
+right margin. Fresh and salt water.
+
+
+Amphisia kessleri Wrzes. '77.  Fig. 51.
+
+Synonyms: _Trichoda gibba_ Müller; _Oxytricha gibba_ Stein '59; _O.
+velox?_ Quen. '69; _O. kessleri_ Wrzes. '77.
+
+Body elongate, slightly sigmoid and swollen in the center, about
+3-1/2 times as long as broad; the rounded anterior end is turned to
+the left, the similarly rounded posterior end to the right; both ends
+taper slightly. The peristome is long and narrow, with a distinct
+adoral zone which appears broken in its course. To the right of this
+adoral zone is a single line of preoral cilia. On the right border of
+the peristome is an undulating membrane. The three frontal cirri form
+a triangle and the five smaller anal cirri form a continuous line
+with the broken row of ventral cirri. There are two and one-half rows
+of ventral cirri and the marginal cirri are drawn in until they are
+ventral in position.
+
+Length 135µ; greatest width 40µ.
+
+
+[Illustration: Fig. 51.--_Amphisia kessleri_.]
+
+
+This variety differs from _O. kessleri_ as described by Wrzesniowski
+in having three frontal cirri instead of four. Another difference
+is in the structure of the nuclei and in their position. These
+differences are too minute to warrant a specific name. _O. velox_ of
+Quennerstedt is probably the same as _0. kessleri_, but differs in
+having three complete rows of ventral cirri. _O. velox_ has three
+frontal cirri in a line, thus differing from the Woods Hole form.
+
+
+KEY TO THE MARINE GENERA OF EUPLOTIDÆ.
+
+Diagnostic characters: Cilia, as well as the frontal, marginal, and
+ventral cirri, very much reduced; the anal cirri, on the other hand,
+are always present. The macronucleus is band-form.
+
+1. Frontal cirri more than 8              2
+
+   Frontal cirri less than 8              3
+
+2. Eleven marginal cirri on the left      Genus _Certesia_
+   side; 11 frontal cirri
+
+   Four marginal cirri, 2 on each         Genus *_Euplotes_
+   side; 9 to 10 frontal cirri
+
+3. Seven frontal, 5 anal, 3 right         Genus *_Diophrys_
+   marginal, and 2 left marginal
+   cirri
+
+   No frontal, 5 anal, 3 right,           Genus *_Uronychia_
+   and 2 left marginal cirri
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EUPLOTES (Ehr. 1831) Stein '59.
+
+(Ehrenberg '31, '38; Stein '59; Cl. & Lach. '58; Quennerstedt '65,
+'67, '69;  Bütschli '88; Kent '81; Gourret & Roeser '88; Möbius '88.)
+
+Small to medium-sized forms. Rigid in form, colorless, or green by
+chlorophyl. They are quite flat on the ventral surface but decidedly
+arched dorsally, and the contour is usually oval. The anterior end is
+broadly rounded to truncate; the posterior end is similarly rounded,
+or may be somewhat pointed. The mouth is placed centrally or near
+the left margin, and from it the right edge of the peristome forms a
+curved line to the left, which bends forward, thus making the greater
+part of the left edge the peristomial area. In front the peristome
+bends sharply to the right and extends as far as the right end of the
+adoral zone. Upon the frontal and median ventral surface are 9 to 10
+great cirri (_Bauchwimpern_ of Stein). Posteriorly five great anal
+cirri stretch out beyond the posterior body margin. In addition to
+these there are two smaller marginal cirri upon the left body edge,
+and two similar ones on the hinder part of the body. The dorsal
+surface is rarely smooth, but usually is marked by longitudinal
+ridges, and rows of dorsal bristles have been described. The single
+contractile vacuole lies on the right side in the region of the
+anal cirri, sometimes just above them, sometimes below. The anus is
+posterior and on the right side. The characteristic macronucleus is
+long and band-form, its main portion being usually on the left side
+with an anterior and a posterior arm toward the right. Movement is
+rapid swimming, which, however, is frequently broken by creeping
+periods, during which the animals appear to be examining the foreign
+body on which they creep.
+
+Fresh and salt water.
+
+
+Euplotes charon Ehr.  Fig. 52.
+
+Synonyms: _Trichoda charon_ Müller; _Ploesconia charon_; _P.
+affinis_, _subrotunda_, _radiosa_, _longiremis_, Dujardin '41.
+
+The body is oval, small, and somewhat variable in length. The
+carapace is strongly marked upon the dorsal side by deep longitudinal
+grooves, 6 to 8 in number; the grooves may be absent, however. The
+adoral zone extends to the posterior third of the body, the mouth
+and oesophagus are directed anteriorly. There are 10 ventral cirri,
+7 of which are on or near the frontal border and 3 near the right
+edge. There are 5 posterior cirri and 4 anal cirri, of much smaller
+size. The cirri may or may not be fimbriated, the latter condition
+indicating the approaching disintegration of the body and is
+abnormal. The macronucleus is long and band-formed or horseshoe
+shape. The contractile vacuole lies on the right side dorsal to the
+posterior cirri.
+
+Fresh and salt water. Length 45µ; diameter 25µ.
+
+
+[Illustration: Fig. 52.--_Euplotes charon_, dorsal and ventral
+aspects.]
+
+
+Euplotes harpa Stein.  Fig. 53.
+
+The body is elongate, oval, somewhat widened anteriorly, and has
+rounded ends. The frontal margin is three-toothed. Ten ventral cirri.
+Dorsal surface provided with 8 longitudinal markings. The peristome
+is long and broad, with considerable variation. The adoral zone
+consists of powerful membranelles arranged in a continuous curve
+from the mouth to the extreme right frontal margin. Seven of the 10
+ventral cirri are situated at the anterior extremity; the remainder
+are arranged in a triangle on the right edge. The anal cirri, 5 in
+number, are long and stiff; the marginal cirri smaller and finer. The
+nucleus and contractile vacuole are similar to those of the preceding
+species.
+
+Length 95µ; width 54µ.
+
+
+[Illustration: Fig. 53.--_Euplotes harpa_.]
+
+
+Genus DIOPHRYS Dujardin '41.
+
+(Bütschli '88.)
+
+Medium size, colorless to yellow, rigid in form. The body contour
+is oval, the anterior end being rounded or slightly reduced, the
+posterior end usually cut in on the right side. The peristome is
+broad but less extensive than in _Euplotes_, and may extend beyond
+the middle of the body. Its right edge is convex toward the right
+side, extends forward and does not turn again to the right. The
+anterior ventral surface has 7 to 8 scattered cirri and just behind
+the mouth is a transverse row of large anal cirri. In the sharp
+in-cut of the posterior end are three great angular cirri. Two
+lateral cirri are placed on the left of the median line between
+the mouth and the anal cirri, and usually in a slight hollow. The
+contractile vacuole is on the right side in the vicinity of the
+anal cirri. The macronucleus is in two parts, each band-form, one
+anterior, the other posterior in position. Movement is rapid and
+steady. Salt water.
+
+
+Diophrys (Styloplotes) appendiculatus Stein '59.  Fig. 54.
+
+Synonyms: _Styloplotes appendiculatus_ Stein '59; Kent '81;
+Quennerstedt '67, etc.
+
+The general form resembles _Euplotes_. Its outline is oval and
+regular except at the posterior end on the right side, where there is
+a considerable indentation. The frontal margin is characterized by a
+row of powerful membranelles, which become smaller at the peristome
+and at the mouth they are of characteristically small size. The
+ventral cirri are 7 in number. Five of them are in one row from the
+anterior end down the right side nearly to the anal cirri; 1 is on
+the frontal border between the first two; 1 lies just anterior to the
+second anal cirrus from the right side. The 5 anal cirri are large
+and powerful and extend some distance beyond the posterior end of the
+body. In all specimens observed these cirri curve to the left. Dorsal
+to the anal cirri and placed deep into the dorsal pit are 3 large,
+sharply curved cirri, which in most cases are fimbriated, but when
+the specimens are normal these are pointed and curve abruptly to the
+right. Two smaller cirri lie to the left of the group of anal cirri.
+The peristome is well-marked by the adoral zone, and upon its right
+border there is a row of cilia, and a similar row of cilia runs along
+the base of the oral membranelle. The macronucleus is double and
+consists of two elongate cylindrical masses lying parallel with
+one another. One of these is in the anterior region; the other is
+posterior. The contractile vacuole lies dorsal to the anal cirri
+and anterior to the three dorsal cirri. The movement and general
+activities resemble those of _Euplotes_.
+
+Length 50µ; diameter 25µ.
+
+
+[Illustration: Fig. 54.--_Diophrys appendiculatus_.]
+
+
+Genus URONYCHIA Stein '52.
+
+(Stein '59, '67; Quennerstedt '67; Kent '81; Bütschli '88.)
+
+Medium-sized colorless ciliates of usually constant body form. The
+body is somewhat short and oval in outline. The anterior end is
+broadly truncate, the posterior end rounded or slightly pointed. The
+ventral and dorsal surfaces are considerably arched and the latter
+usually has a number of rows of longitudinal stripes. The open
+peristome is broad and reaches back to the middle of the ventral
+surface and beyond. According to Stein, the two edges can approach
+each other, thus opening and closing the peristomial area. Its right
+edge forms a greater angle with the front edge than in the genus
+_Euplotes_, and the left edge forms a greater angle with the front
+edge than in that genus. The left edge also appears to cover over the
+adoral zone slightly. There are no ventral cirri in front, but on the
+posterior ventral surface are 7 great springing cirri. Five of these
+are inserted on the right aide in a deep in-sinking, and the other 2
+in a similar depression on the left ventral surface. Above the 5
+right-side cirri, _i.e._, dorsal to them, but in the same depression,
+are 3 angular cirri. A few edge cirri are found to the left of them
+and another to the right of the 5 cirri. The contractile vacuole is
+on the left side between the main groups of cirri. The macronucleus
+is band-form or spherical, and is situated in the middle region of
+the body. Movement consists in forward swimming with sudden springs.
+
+Salt water.
+
+
+Uronychia setigera, n. sp.  Fig. 55.
+
+This species is very common in the Woods Hole waters. It is small,
+colorless, and very active. The most characteristic feature is
+the posterior end with its relatively enormous cirri, which are
+apparently large enough for an animal four times its size. The form
+is ovoid, widened posteriorly.
+
+The ventral surface is flat and has two excavations in the posterior
+end. The right hollow is larger and contains 5 great cirri of unequal
+size, the extreme right one being the largest. The left hollow
+contains 2 cirri, also of dissimilar size. Dorsal to the 5 right
+cirri are 3 sickle-formed cirri, which are usually fimbriated. These
+are pointed and curve regularly to the left. The peristome is wide
+and open, and a small pocket-like hollow on its left border indicates
+the region of the mouth. The adoral zone runs into this pocket
+and the mouth is located in its lower right-hand corner. In _U.
+transfuga_ the right border is generally described as having a
+membrane of extreme delicacy. I was unable to see such a membrane in
+this form, but in its place there are 2 flagella-like cirri extending
+from the margin of the mouth-opening into the peristome, and these
+vibrate slowly. I do not believe these could be the moving edge of an
+undulating membrane, for they are quite distinct. The macronucleus is
+spherical instead of band-form, and a single micronucleus is closely
+attached. This is unlike the European species _U. transfuga_, in
+which the nucleus is elongate. The contractile vacuole lies between
+the two sets of posterior cirri. There are no marginal folds like
+those of the European species.
+
+Length 40µ; width 25µ. Common.
+
+
+[Illustration: Fig. 55.--_Uronychia setigera_.]
+
+
+Genus ASPIDISCA Ehr. 1830.
+
+(Perty '52; Cl & Lach. '58; Stein '59; Quennerstedt '65, '67, '69;
+Mereschowsky '79; Kent '81; Bütschli '88.)
+
+Small, colorless, and rigid forms, with nearly circular to oval
+contour. The left side is usually straight, or at least but slightly
+convex. The right side is much more convex, and the right margin is
+considerably thickened. The ventral side is flat, the dorsal surface
+convex, with from one to several longitudinal ridges which run more
+or less parallel with the right edge. The peristome is limited to the
+left edge, where it forms a small depression which may or may not
+reach the anterior border, but which in no case runs around the
+anterior margin. The left peristome margin in some cases grows
+over the peristome depression toward the right, thus making a sort
+of cover for the peristome. In the posterior region is a deep
+depression, from which 5 to 12 cirri take their origin. Seven or 8
+cirri are placed in the anterior half of the ventral surface and
+are arranged more or less in rows. The anus is on the right side in
+the region of the anal cirri (Stein). The contractile vacuole is
+generally on the right side and similarly located. The macronucleus
+is a horseshoe-shaped body. Movement rapid, somewhat in circles, and
+rather uniform.
+
+Fresh and salt water.
+
+
+Aspidisca hexeris Quennerstedt '67.  Fig. 56.
+
+The carapace is elliptical, about 1-1/2 times as long as broad,
+rounded at the extremities. The left border of the carapace bears a
+spur-like projection. The ventral cirri are short and thick, and are
+very characteristic of the species. When moving slowly they look much
+like nicely-pointed paint brushes, but when the animal is compressed
+they quickly become fibrillated, and then look like extremely old and
+worn brushes. These cirri are placed in depressions in the ventral
+surface and each one appears to come from a specific shoulder. At the
+posterior end an oblique hollow bears 6 unequal cirri placed side
+by side. The extreme right cirrus is the largest, and they become
+progressively smaller to the opposite end. Dorsal to these lies the
+contractile vacuole. The peristome is in the posterior half of the
+body and an undulating membrane extends from it into the oesophagus.
+The dorsal surface is longitudinally striated by 5 or 6 lines, which
+are usually curved. The nucleus is horseshoe-shaped and lies in the
+posterior half of the body. Length 68µ; diameter 48µ.
+
+
+[Illustration: Fig. 56.--_Aspidisca hexeris_.]
+
+
+This form was incorrectly mentioned as _Mesodinium_ sp. by Peck '95:
+
+In the figure given by Quennerstedt there are only 7 ventral cirri.
+In the Woods Hole form there are 8, 7 of which are anterior, 6 of
+them about one central one. The eighth cirrus is by itself, near the
+base of the largest posterior cirrus. These cirri, in spite of their
+size, are easily overlooked and more easily confused, but by using
+methylene blue they can be seen and counted.
+
+
+Aspidisca polystyla Stein.  Fig. 57.
+
+This species is similar to _A. hexeris_, but is smaller, very
+transparent, and without the spur-like process on the left edge of
+the carapace. The chief difference, however, lies in the number of
+anal cirri. These are 10 in number and they are arranged obliquely as
+in the preceding species, with the largest one on the right and the
+smallest on the left. The ventral cirri are 8 in number, and are
+arranged in two rows, one of which, the right, has 4 cirri closely
+arranged, the other having 3 cirri close together and one at some
+distance, near the largest anal cirrus. The peristome, contractile
+vacuole, and nucleus are similar to the preceding. Length 36µ; width
+22µ.
+
+
+[Illustration: Fig. 57.--_Aspidisca polystyla_.]
+
+
+Stein assigns only 7 ventral cirri to this species, but he also
+describes 2 very fine bristle like cilia (p. 125) and pictures them
+in figs. 18, 19, 20, and 21 of his Taf. III in the same relative
+position as my eighth cirrus. I am positive that cilia do not occur
+on the ventral face of this form, and that the characteristic cirri
+are the sole locomotor organs.
+
+
+KEY TO FAMILIES OF PERITRICHIDA.
+
+a. Peristome drawn out into               Family _Spirochonidæ_
+   funnel-like process; parasitic
+
+b. Adoral zone and circlet of cilia       Family _Lichnophoridæ_
+   at opposite end. Adoral zone           (one genus, *_Lichnophora_)
+   left-wound. Parasitic.
+
+c. Adoral zone a left-wound spiral.       Family _Vorticellidæ_
+   Attached or unattached forms.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LICHNOPHORA Claparède '67.
+
+(Gruber '84; Fabre-Domergue '88; Bütschli '88; Wallengren '94;
+Stevens 1901.)
+
+Small or medium-sized colorless animals, extremely elastic and
+flexible. The anterior part, bearing the adoral zone, is round or
+oval in ventral view, and has a flat ventral and a highly arched
+dorsal surface. The posterior end of the animal is reduced to a
+stalk-like structure which is broadened at the extremity to form
+a sucking disk. The surface of this disk and the surface of the
+peristome may be brought into the same plane by the characteristic
+bending of the stalk portion. A ciliated girdle is placed at the
+edge of the sucking disk. A well-developed adoral zone incloses the
+peristome; it begins at the mouth on the left side and includes
+nearly all of the peristome in its left-wound spiral, the extremity
+approaching closely the end near the mouth. The macronucleus is a
+long-beaded structure, or it may be in several parts connected by
+strands (Gruber). The contractile vacuole is on the left side in the
+region of the mouth. Salt water.
+
+
+Lichnophora macfarlandi Stevens.  Fig. 58.
+
+The body is elongate; oral disk variable in form, attachment disk
+clearly defined and constant. The stalk is very contractile and
+elastic, constantly changing in shape. When detached from the host
+the animal moves with a very irregular and indefinite motion. When
+attached it moves freely over the surface on its pedal disk. The
+latter is bordered by four membranes composed of cilia. A distinct
+axial fiber extends from the pedal disc to the peristome and gives
+off a number of branches. This fiber is analogous to the myonemes
+in _Vorticella_. An indistinct longitudinal furrow can be made out
+occasionally. The nucleus is in 5 or 6 separate pieces, of which 1
+is found in the pedal disk and 1 or 2 in the neck.
+
+On the egg capsules of _Crepidula plana_; also reported upon annelids
+at Woods Hole.
+
+Length 60µ from disk to extremity of the peristomial disk.
+
+
+[Illustration: Fig. 58.--_Lichnophora macfarlandi_.]
+
+
+This form does not agree in all respects with Stevens's species, but
+the agreement is so close in other respects that I believe it can be
+safely identified as _L. macfarlandi_. The mode of life is different,
+and the macronucleus is different, there being from 25 to 30
+fragments in Stevens's form and only 5 or 6 in the present one. There
+is, however, the same evidence of chain formation in both of them.
+The length of the oral cilia in  Stevens's form is 18µ in fixed and
+30µ in living forms. In the Woods Hole form the cilia are not more
+than half that length.
+
+
+KEY TO THE MARINE GENERA OF VORTICELLIDÆ.
+
+Diagnostic characters: Attached or unattached forma of peritrichous
+ciliates in which the adoral zone seen from above forms a right-wound
+spiral. A secondary circlet of cilia around the posterior end may be
+present either permanently or periodically.
+
+1. Posterior ciliated girdle              3
+   permanent around an attaching disk
+
+2. Posterior ciliated girdle,             4
+   temporary during motile stage
+
+3. Body cylindrical:
+
+  (a) With ring of stiff bristles         Genus _Cyclochæta_
+      above the ciliated girdle
+
+  (b) Without accessory ring of           Genus _Trichodina_
+      bristles; with velum
+
+         Body conical; general            Genus _Trichodinopsis_
+         surface ciliated
+
+4. No test and no stalk                   Genus _Scyphidia_
+
+5. No test; with stalk containing         8
+   contractile thread
+
+6. No test; with stalk but without        Genus _Epistylis_
+   contractile thread
+
+7. With a test; with or without           Genus *_Cothurnia_
+   a stalk
+
+8. Individuals solitary                   Genus *_Vorticella_
+
+   Individuals colonial;                  Genus *_Zoothamnium_
+   entire colony contractile
+
+   Individuals colonial; parts            Genus _Carchesium_
+   only of the colony contractile
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus VORTICELLA (Linnæus 1767) Ehr. '38
+
+(Bell Animalcule Leeuwenhoek 1675; Ehrenberg '38; Dujardin '41; Stein
+'51; Cl. & Lach. '58; Greeff '70; Bütschli '88; Kent '81; Stokes '88;
+etc.)
+
+Medium-sized ciliates of general bell-like form. They may be
+colorless, or yellow and green through the presence of Zoochlorella.
+When not contracted, the peristome end is widespread, rarely
+narrowed. The adoral zone and peristome agree with the details given
+in the family characteristics. The chief character is the attachment
+of the posterior end by means of a single, longer or shorter, stalk,
+which contains a highly contractile thread easily distinguished
+in the living animal. Another character is the absence of colony
+formation. Contractile vacuole, single or double, usually connected
+with a sac-like reservoir. The macronucleus is invariably long and
+band-formed, with attached micronucleus. Fresh and salt water.
+
+So many species of _Vorticella_ have been described that the task of
+collecting data and of arranging the synonyms is extremely irksome
+and difficult. Stokes enumerates 66 species, inhabiting fresh and
+salt water, and several other new species have been added since his
+work. I am impressed with the fact that new species have been created
+without proper regard for the manifold variations which nearly all
+of the _Ciliata_ show, and I believe the 66 species might be safely
+reduced to 12 or 15.
+
+
+Vorticella patellina Müller.  Fig. 59.
+
+Body campanulate, widest at anterior border, from which it tapers
+directly to the pedicle. The diameter of the peristome is a little
+larger than the length of the body. The ciliary disk is but little
+elevated. The cuticle is not striated and the body plasm is quite
+transparent. Length 52µ.
+
+
+[Illustration: Fig. 59.--_Vorticella patellina_.]
+
+
+Vorticella marina Greeff.  Fig. 60.
+
+The body is conical but variable, and may he short or elongate, so
+that relative length and breadth offer no chance of identification.
+In general the body is campanulate. The distinguishing feature is the
+transverse annulation of the bell.
+
+Small, but common, and grows in small social groups. Length 35µ.
+
+
+[Illustration: Fig. 60.--_Vorticella marina_.]
+
+
+Genus ZOOTHAMNIUM (Bory de St. Vincent 1824) Stein '38, '54.
+
+Colorless and highly contractile forms growing in small or large
+colonies. The form and structure of the individuals is not different
+from _Vorticella_. The colonies are usually richly branched upon
+the dichotomous plan and the entire colony is contractile. The main
+character is that with each division of the individual the stalk
+also divides, each daughter cell getting one-half of the parent stem.
+The stems therefore remain in communication, so that a simultaneous
+contraction results, and the colony as a whole is withdrawn. In some
+species so-called macrogonidia, or larger sexual individuals, are
+developed alongside the usual ones. Fresh and salt water.
+
+
+Zoothamnium elegans D'Udekem '64?  Fig. 61.
+
+The bodies are variable--peristomial border widely dilated, tapering
+and attenuate posteriorly. The pedicle is slender, smooth, and
+transparent, and branches sparsely at its distal extremity. There
+are but few zooids (3 to 4). The ciliary disk projects conspicuously
+beyond the peristomial border. The pharyngeal cleft is very distinct
+and extends beyond center of body. Length of body 80µ.
+
+
+[Illustration: Fig. 61.--_Zoothamnium elegans_.]
+
+
+Genus COTHURNIA (Ehr. '31) Clap. & Lach. '58.
+
+Colorless forms of medium size-in some cases they may be green
+by Zoochlorella. The general structure is similar to that of
+_Vorticella_, but the individuals are elongate and occupy houses. The
+macronucleus is invariably long and band-form. The distinguishing
+character is the colorless or brownish lorica of quite variable form
+but always attached. These houses may be finger-formed, with widened
+center, or widened mouth, or constricted mouth, and the like.
+Ring-formed swellings are frequently developed. Sometimes the mouth
+becomes twisted and the lorica is therefore bilateral. The houses
+are attached either directly to some foreign object or by means of
+a short stalk. The animals are similarly fastened to the lorica,
+sometimes directly, sometimes by means of a short stalk. When they
+contract they draw back to the bottom of the lorica; when expanded
+they usually stretch out of the mouth opening. In some forms there
+is an operculum, by means of which the opening of the shell can be
+closed when the animal is retracted. Fresh and salt water.
+
+The number of species of _Cothurnia_ has become so great that the
+difficulty in placing forms is almost sufficient to discourage the
+systematist; as Bütschli well remarks, the variations in the theca
+have been made the basis of new species so many times that the
+genus is almost as confused as _Difflugia_ among the rhizopods or
+_Campanularia_ among the hydroids. The length of cup, of stalk,
+the presence of annulations on stalk or cup, etc., have given rise
+to many specific names, the majority of which I believe can be
+discarded. According to such differentials the same branch of an alga
+holding a hundred specimens of _Cothurnia crystallina_ yield 10 or 12
+species, whereas they are merely growth stages of one and the same
+form.
+
+
+Cothurnia crystallina Ehr.  Fig. 62.
+
+Synonyms: _Vaginicolla crystallina_ Ehr., Perty, Eichwald; _V.
+grandis_ Perty; _V. pedunculata_ Eichwald; _Cothurnia crystallina_
+Claparède & Lachmann, D'Udek.; _C. gigantea_ D'Udek; _C. maritima_,
+_C. crystallina_ Cohn; _C. grandis_ Meresch.
+
+The form of the cup shows the greatest differences; sometimes it is
+cylindrical, sometimes elongate thimble-shape, sometimes pouch-shape,
+corrugated or smooth on the sides, and wavy or smooth on border.
+Frequently the basal part becomes stalk-like, but this is very short.
+When present, the stalk may or may not have a knob-like swelling. The
+animal within the cup may or may not be borne on a stalk, and this
+stalk may or may not be knobbed. The cups are colorless or brown. The
+animal is very contractile and may stretch half its length out of the
+cup or retract well into it. There is no operculum. The length of the
+cup varies from 70µ to 200µ (_C. gigantea_; _Vag. grandis_, etc.).
+From Entz.
+
+There is nothing to add to Entz's characterization of this species,
+which is found both in fresh and salt water. The variability of the
+cup and stalk is quite noticeable in the Woods Hole forms.
+
+
+[Illustration: Fig. 62.--_Cothurnia crystallina_.]
+
+
+Cothurnia imberbis Ehrenberg, var. curvula Entz.  Fig. 63.
+
+Synonyms: _C. imberbis_ Kent et al.; _C. curvula_ Entz; _C. socialis_
+Gruber?
+
+The lorica is swollen posteriorly, narrowest at the oral margin, bent
+on its axis and is supported on a short stalk. It is perfectly smooth
+and without annulations. The animal itself has no definite stalk.
+When fully expanded the animal emerges but slightly from the margin
+of the cup. Fresh and salt water. On red algæ. Dimensions of Woods
+Hole form: Cup 50 to 55µ long; greatest diameter 22µ; length of stalk
+4 to 5µ.
+
+
+[Illustration: Fig. 63.--_Cothurnia imberbis_.]
+
+
+Cothurnia nodosa Claparède & Lachmann.  Fig.64.
+
+   A. Smooth cup.--_Cothurnia maritima_ Ehr., Eichwald, Stein, Kent.
+
+   B. Cross-ringed cup.--_C. pupa_ Eichwald, Stein, Cohn; _C. nodosa_
+      Cl & L.; _V. crystallina_ Entz '78; _C. pontica_ Meresch.,
+      Kent; _C. cohnii_ and _pupa_ Kent; _C. longipes_ Kellicott '94.
+
+The cup is elongated, swollen centrally, tapering at oral end
+and conical at base or rounded. Oral opening either circular or
+elliptical. Cross rings may or may not be present, and the cup is
+either smooth or annulate. Length of cup 70µ to 80µ. The stalk which
+supports the cup is extremely variable in length. The animal is borne
+upon a stalk of variable length within the cup.
+
+Entz states that the many variations which this species exhibits run
+into each other so gradually that he does not believe it wise to
+separate them. The Woods Hole forms which I found on algæ of various
+kinds were nearly of a size, and did not vary much from the one
+figured. Kellicott '94 described a _Cothurnia_ from Woods Hole under
+the name of _C. longipes_, which I believe is only a long-stemmed
+variety of _C. nodosa_. My form has the following dimensions: Cup
+75µ; cup stalk 38µ; animal stalk 14µ.
+
+
+[Illustration: Fig. 64.--_Cothurnia nodosa_.]
+
+
+KEY TO FAMILIES OF SUCTORIA.
+
+a. Unattached forms; ventral cilia        _Hypocomidæ_
+   present; one suctorial tentacle
+
+b. Attached forms; thecate and            _Urnulidæ_
+   athecate tentacles simple,
+   one or two in number
+
+c. Thecate; posterior end of cup          _Metacinetidæ_
+   drawn out into stalk; walls
+   perforated for exit of tentacles
+
+d. Stalked or unstalked; globular;        _Podophryidæ_
+   tentacles of different kinds, some     (2 genera *_Ephelota_,
+   knobbed, others pointed                *_Podophrya_)
+
+e. Naked or thecate; stalked or not;      _Acinetidæ_
+   tentacles numerous, usually
+   knobbed and all alike
+
+f. Naked; athecate; tentacles             _Dendrosomidæ_
+   numerous, all alike, knobbed and
+   grouped in tufts. They may be
+   simple or branched.
+
+g. Sessile forms resting on basal         _Dendrocometidæ_
+   surface or on a portion raised
+   like a stalk; tentacles many;
+   short and knobbed; distributed
+   on apical surface or localized
+   on branched arms
+
+h. Stalked or sessile; tentacles          _Ophryodendridæ_
+   long, rarely knobbed, supported
+   on proboscis-like processes
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PODOPHRYA Ehr. '33.
+
+(Bütschli '88; Stein '59; Perty '52; Cienkowsky '55; Quenn. '69;
+Hertwig '77; Maupas '81.)
+
+The body is globular, with tentacles radiating in all directions. The
+tentacles may be very short or very long. The stalk also is either
+short or long, and some species form stalks but rarely (_P. libera_).
+The macronucleus is centrally placed and globular to ovoid in form.
+The contractile vacuole is usually single. Reproduction takes
+place by division; the distal half developing cilia and becoming a
+swarm-spore. Fresh and salt water.
+
+
+Podophrya gracilis, n. sp.  Fig. 65.
+
+Of all the _Podophrya_ that have been described not one approaches
+this minute form in the relative length of the stalk. The body is
+spherical and is covered with short capitate tentacles. The stalk is
+extremely slender, bent, and without obvious structure. There are
+one or two contractile vacuoles in the distal half of the body. The
+nucleus is small and is situated near the insertion-point of the
+stalk. Reproduction not observed. Diameter of body 8µ; length of
+stalk 40µ. Only one specimen seen.
+
+
+[Illustration: Fig. 65.--_Podophrya gracilis_.]
+
+
+Genus EPHELOTA Str. Wright '78.
+
+(Bütschli '88; Ishikawa '96; Sand '98.)
+
+Small to medium-sized and large forms; colorless to brown. The body
+is globular or oval or wedge-shape, sometimes quadrangular. The stalk
+is variable, sometimes 1 mm. in length. The diameter of the stalk
+increases from the point of attachment to the body of the animal;
+it is usually striated either longitudinally or transversely, or
+both. The tentacles are of two kinds and are usually confined to
+the anterior half of the body. Some are long and sharp-pointed
+and adapted for piercing; others are short, cylindrical, usually
+retracted and capitate, adapted for sucking. Contractile vacuoles
+vary from one to many. The macronucleus is nearly central in position
+and usually of horseshoe shape, but is frequently branched and
+irregular. Reproduction is accomplished by external multiple budding,
+usually from the anterior half of the body. Salt water.
+
+
+Ephelota coronata Str. Wright.  Fig. 66.
+
+Synonyms: _Hemiophrya gemmipara_ S. K.; _Podophrya gemmipara_
+Hertwig.
+
+The body is spheroidal, ovate, or pyriform, with numerous
+sharp-pointed tentacles and a few straight, uniform tentacles. The
+stalk is about three times the length of the body and tapers from its
+widest part at the insertion in the body to the narrowest part at the
+point of attachment. It may or may not be longitudinally striated.
+This is one of the commonest of the _Suctoria_ found at Woods Hole.
+It is usually present on Campanularian hydroids, but may be found on
+algæ and Bryozoa.
+
+Length of body 90µ to 200µ.
+
+
+[Illustration: Fig. 66.--_Ephelota coronata_.]
+
+
+Genus ACINETA Ehr. '33, Bütschli '88.
+
+(Stein '54, '59; Claparède & Lachman '58; Quennerstedt '67; Hertwig
+'76; Mereschowsky '79; Entz '84; Kent '81; Maupas '83; Gruber '84;
+Gourret & Roeser '86, and others.)
+
+Small to medium-sized forms. The distinguishing feature is that the
+stalk is swollen at the distal extremity to form a cup or basin in
+which the animal rests. The cup may be developed until the body is
+nearly inclosed. The macronucleus is spherical or band form. The
+contractile vacuole is usually single. Budding, so far as known, is
+endogenous. Fresh and salt water.
+
+
+Acineta divisa Fraipont '79.  Fig. 67.
+
+This extremely graceful form is common on Bryozoa at Woods Hole. The
+cup is shaped like a wine glass and is specifically characterized by
+a cup-formed membrane upon which the animal rests. The animal thus
+has the appearance of being suspended on the edge of the cup. The
+stalk is slender and about 4 times the length of the body. The
+tentacles are all capitate and distributed, and about 2-1/2 times the
+body length. They sway back and forth very slowly. The nucleus is
+spherical and central in position. The contractile vacuole lies near
+the periphery.
+
+Length of body 27µ; of stalk 100µ; of extended tentacle 65µ.
+
+
+[Illustration: Fig. 67.--_Acineta divisa_.]
+
+
+Acineta tuberosa Ehr.  Fig. 68.
+
+Large forms of _Suctoria_ with tentacles arranged in fascicles. The
+stalk is variable in length and the cup is frequently so delicate
+that it can barely be made out. A specific characteristic is the
+break in continuity of the cup at different points, and through these
+places the tentacles emerge in bundles. The tentacles are capitate
+and in the Woods Hole form, 15 in number in each of the two bundles.
+The endoplasm is granular and yellowish in color. The coloring matter
+is frequently arranged in patterns. The nucleus is spheroidal. The
+contractile vacuole is in the anterior third of the body about midway
+between the bundles of tentacles. Reproduction not observed.
+
+Length of body 330µ.
+
+
+[Illustration: Fig. 68.--_Acineta tuberosa_.]
+
+
+Genus TRICHOPHRYA Clap. & Lach. '58.
+
+(See Kent '81; Entz '84; Bütschli '88; Sand 1901.)
+
+Small forms to medium size; no cups or stalks. The body is spherical
+to elongate, usually, however, more or less irregularly lobed and
+changeable. The tentacles are in fascicles which are usually borne
+upon lobed or swollen places. The body is always more or less spread
+out. Contractile vacuoles variable. The macronucleus is spherical,
+elongate, band-formed or horseshoe-shaped. Reproduction takes place
+by endogenous budding, and the swarm spores are flat or lenticular
+with a distinct ciliary girdle. They are frequently parasitic. Fresh
+and salt water.
+
+
+Trichophrya salparum Entz '84.  Fig. 69.
+
+Bütschli '88; Schewiakoff '93; _Trichophrya ascidiarum_ Lachmann '59;
+René Sand 1901.
+
+The body is somewhat cup-form, with a large, flat base. The anterior
+border is rounded, each of the ends being somewhat truncate and
+carrying a bundle of tentacles all capitate and similar. These may be
+continued internally as far as the nucleus (Sand). The cytoplasm is
+uncolored, but may contain some brilliant granules. The nucleus is
+granular, and spherical, band or horseshoe formed.
+
+
+[Illustration: Fig. 69.--_Trichophrya salparum_.]
+
+
+This species was found by Dr. G. Hunter on the branchial bars of the
+Ascidian _Molgula manhattensis_, where great numbers of them are
+often parasitic.
+
+
+
+
+LIST OF REFERENCES.
+
+
+
+
+
+AUERBACH, L. '54. Ueber Encystierung von Oxytricha pellionella. Zeit.
+      wiss. Zool., V, 1854.
+
+---- '55. Ueber die Einzelligkeit der Amoeben. Zeit. wiss. Zool.,
+      VII, 1855.
+
+BALBIANI E. G. '61. Recherches sur les phénomènes sexuelles des
+      Infusoires. Jour. de la physiol:, IV, 1861.
+
+---- '85. Sur un Infusoire parasite du sang de l'Aselle aquatique.
+      Rec. zool. Suisse, II, 1885.
+
+BERGH, R. S. '79. _Tiarina fusus_ Cl. & Lach. Vid. Med. f. d. Nat.
+      Foren. Kjobenhavn.
+
+---- '82. Der Organismus der Cilioflagellaten.  Morph. Jahr., VII, p.
+      177.
+
+BRADY, H. B. '79. Report on the Foraminifera dredged by H. M. S.
+      _Challenger_ during the years 1873-1876. Challenger Reports,
+      Zoology, IX.
+
+BRANDT, K. '96. Die Tintinnodeen. Bibliot. Zoolog., XX, 1896.
+
+BÜTSCHLI, O. '76. Studien über die ersten Entwickelungsvorg. der
+      Eizelle, die Zelltheilung, und die Conjugation der Infusorien.
+      Abhand. der Senck. naturf. Ges. Freiburg, X, 1876.
+
+---- '83-'88. Die Protozoen. Bronn's Klassen u. Ord. des Tierreichs.
+
+CARPENTER, W. B. '56. Researches on the Foraminifera. Phil. Trans.
+      (2), p. 547.
+
+CARTER, H. J. '56. Notes on the fresh-water Infusoria of the island
+      of Bombay. Ann. Mag. Nat. Hist. (2), XVIII.
+
+---- '63. On the coloring matter of the Red Sea. Id. (3), XI.
+
+---- '63a. On _Amoeba princeps_ and its reproductive cells. Id. (3),
+      XII.
+
+---- '64. On fresh-water Rhizopods of England and India. Id. (3),
+      XIII, p. 13.
+
+---- '65. On the fresh- and salt-water Rhizopods of England and
+      India. Id. (3), XV, p. 277.
+
+CIENKOWSKY, L. '55. Bemerkungen über Stein's Acinetenlehre. Bull.
+      Phys. Math. Acad., St. Petersburg, XIII, p. 297 (also in Ann.
+      Mag. Nat. Hist. (3), XIII).
+
+---- '55. Ueber Cystenbildung bei Infusorien. Zeit. wiss. Zool., VI,
+      p. 301.
+
+---- '61. Beiträge zur Kenntniss der Monaden. Arch. f. mik. Anat., I,
+      1865, p. 203.
+
+CLAPARÈDE, E. '54. On _Actinophrys sol_. Ann. Mag. Nat. Hist. (2),
+      XV, 1854.
+
+---- '60. Recherches sur les annélides, etc., observés dans les
+      Hébrides. Mém. Soc. phys. d'hist. nat., Genève, XVI, 1860.
+
+---- '67. Miscellanées zoologiques. Ann. d. sc. nat. zool. (5), VIII,
+      1867.
+
+CLAPARÈDE ET LACHMANN '58-'60. Etudes sur les Infusoires et les
+      Rhizopodes. Mém. Inst. genèvoise, V, VI, VII.
+
+COHN, F. '54. Beiträge z. Entwicklungsges. der Infusorien. Zeit.
+      wiss. Zool. III, 1851; IV, 1853.
+
+---- '57. Ueber Fortpflanzung von _Nassula elegans_ Ehr. Zeit. wiss.
+      Zool., IX, 1857, p. 143.
+
+COSTE, M. '64. Développement des Infusoires ciliés dans une
+      macération de foin. Ann. d. ac. nat. zool.(5), II.
+
+DADAY, E. v. '86.  Ein kleiner Beitrag der Infusorien-Fauna des
+      Golfes v. Neapel. Mitt. Zool. St. Neap., VI, p. 481.
+
+---- '88. Monographie der Familie der Tintinnodeen. Mitt. Zool. St.
+      Neap., VIII, p. 473.
+
+DAVIS, J. '79. On a new species of Cothurnia. Jour. Roy. Mic. Soc.,
+      II, 1879.
+
+DUJARDIN, F. '35. Recherches sur les organismes inférieures. Ann. d.
+      sc. nat. zool. (2), IV, p. 343.
+
+---- '41. Histoire naturelle des Zoophytes infusoires. Paris, 1841.
+
+EHRENBERG, C. G. '31. Ueber die Entwickelung und Lebensdauer d.
+      Infusionsthiere. Abhand. d. Berlin Ak., 1831, p. 1.
+
+---- '38. Die Infusionsthierchen als vollkommne Organismen. Leipzig,
+      1838.
+
+ENGELMANN, Th. W. '78. Zur Physiologie der Contractilen Vacuolen der
+      Infusionsthiere.  Zool. Anz., I, p. 121.
+
+ENTZ, G. '84. Ueber Infusorien d. Golfes v. Neapel. Mitt. Zool. St.
+      Neap., V, p. 289.
+
+---- '85. Zur naheren Kenntniss der Tintinnodeen. Mitt. Zool. St.
+      Neap., VI, p. 185.
+
+FABRE-DOMERGUE, P. '85. Note sur les Infusoires ciliés de la baie de
+      Concarneau. Jour. d. l'anat. et de la phys., XXI, p. 554.
+
+---- '91. Matériaux pour servir a l'histoire des Infusoires ciliés.
+      Ann. d. mic., III, 1890-91, p. 49.
+
+FOL, H. '83. Further contribution to the knowledge of the
+      Tintinnodea. Ann. Mag. Nat. Hist. (5), XII, p.73.
+
+FRANCÉ, R. H. '97. Der organismus der Craspedomonaden. Budapest.
+
+FROMENTEL. E. DE. '74. Etudes sur les microzoaires, etc. Paris, 1874.
+
+GOURRET ET ROESER. '88. Contributions à l'étude des Protozoaires de
+      la Corse. Arch. d. biol., VIII  p. 139.
+
+GREEFF, R. '66. Ueber einige in der Erde lebende Amoeben und andere
+      Rhizopoden. Arch. f. mik. Anat., II, p. 299.
+
+---- '70. Untersuchungen ueber den Bau u. d. Naturgeschichte d.
+      Vorticellen. Arch. f. Naturges., XXXVI, XXXVII.
+
+---- '71. Ueber die Actinophryens oder Sonnenthierchen des
+      Süssenwassers als echte Radiolarien. Sitz. Ber. d. Niederrh.
+      Ges. i. Bonn, XXVIII, p. 4.
+
+---- '75. Ueber Radiolarien u. Radiolarienartige Rhizopoden des
+      Süssenwassers 2.  Arch. f. mik. Anat., XI.
+
+---- '88. Studien über Protozoen. Sitz. Ber. Ges. z. Bef. d. ges.
+      Nat., Marburg, 1888, p. 91.
+
+GRENACHER, H. '68.  Ueber _Actinophrys sol_ Ehr. Verh. phys.-med.
+      Ges. Freiburg (n. F.), I.
+
+GRUBER, A. '83. Beobachtungen an _Chilodon curvidentis_ n. sp.
+      Festschr. 56. Vers. Deutsch. Naturf. gewid. v. d. Naturf. Ges.
+      Freiburg, II, p. 1.
+
+---- '84. Die Protozoen des Hafens v. Genua. Nova Act. d. K.
+      Leop.-Car. Deutsch. Akad. d. Naturf., XLVI, p. 475.
+
+---- '87. Ueber der Bedeutung der Conjugation bei den Infusorien.
+      Ber. d. Naturf. Ges. Freiburg, II, p. 31.
+
+HÆCKEL, E. '73. Zur Morphologie der Infusorien.  Jena Zeit., VII, p.
+      516.
+
+HERTWIG, R. '76. Ueber _Podophrya gemmipara_, nebst Bemerkungen zum
+      Bau u. d. systemat. Stellung d. Acineten. Morph. Jahr., IV,
+      p. 20.
+
+HERTWIG U. LESSER. Ueber Rhizopoden u. denselben nahe stehende
+      Organismen. Arch. F. mik. Anat., X, Suppl., p. 35.
+
+HUXLEY, T. H. '57. On Dysteria, a new genus of Infusoria. Jour. Mic.
+      Sci., V, p. 78.
+
+ISHIKAWA, C. Ueber eine in Misaki vorkommende Art v. Ephelota, etc.
+      Journ. Coll. Sci. Imp. Univ. Tokyo, Japan, X, pt. 2.
+
+JAMES-CLARK, H. '66. On the Spongiæ ciliatæ as Infusoria flagellata,
+      etc. Mem. Bost. Soc. Nat. Hist. (3), I, p. 1.
+
+KENT, W. SAVILLE. '81. Manual of the Infusoria. London, 1881.
+
+KLEBS, G. '84. Ein kleiner Beitrag z. Kenntniss d. Peridineen. Bot.
+      Zeit., XLII, p. 721.
+
+---- '92. Flagellaten Studien 1. Zeit. wiss. Zool., LV.
+
+LABBÉ, A. '95. Sur les Protozoaires marins de Roscoff. Arch. d. zool.
+      expér. (3), N. et R., p. XIV.
+
+LAUTERBORN, R. '94. Beiträge z. Süsswasserfauna der Insel Helgoland.
+      Wiss. Meeresunt. Komm. wiss. Unt. d. Meere Kiel (2), I, p. 215.
+
+LEIDY, J. '77. Remarks upon Rhizopods and notice of a new form. Proc.
+      Ac. Sci. Phila., 1877, p. 293.
+
+---- '79. Fresh water Rhizopods of North America. Washington, 1879.
+
+LIEBERKÜHN, N. '56. Ueber Protozoen.  Notes from a letter to C. Th.
+      v. Siebold. Zeit. wiss. Zool., VIII, p. 307.
+
+MAUPAS, E. '81. Contributions à l'étude des Acinétiens. Arch. d.
+      zool. expér. (1), IX, p. 299.
+
+---- '83. Contributions à l'étude morphologique et anatomique des
+      Infusoires ciliés. Id. (2), I.
+
+---- '83a. Les sucto-ciliés de M. Mereschowsky. Comp. Ren., XCV, p.
+      1381.
+
+---- '88. Recherches expérimentales sur la multiplication des
+      Infusoires ciliés. Arch. d. zool. exper. (2), VI, p. 165.
+
+MERESKOWSKY, C. '78. Studien über Protozoen des nordlichen Russland.
+      Arch. f. mik. Anat., XVI, p. 163.
+
+---- '81. On some new or little-known Infusoria. Ann. Mag. Nat. Hist.
+      (5), VII, 1881.
+
+MOEBIUS, K. '88. Bruchstücke einer Infusorienfauna der Kieler Bucht.
+      Arch. f. Naturg., 1888.
+
+PECK, J. I. '93. On the food of the menhaden. Bull. U. S. Fish Com.,
+      1893, p. 113.
+
+---- '95. The sources of marine food. Bull. U. S. Fish Com., 1895, p.
+      351.
+
+PERTY, M. '49. Mikrosk. Organ. der Alpen u. d. Italien. Schweiz.
+      Mitt. d. Naturf. Ges. in Bern, 164-165.
+
+---- '52. Zur Kenntniss kleinster Lebensformen, etc., Bern.
+
+POUCHET, G. '83; '85. Contributions à l'histoire des Péridiniens
+      marins. Jour. de l'anat. et de la phys., XIX, XXI.
+
+QUENNERSTEDT, A. '65; '67; '69. Bidrag till Sveriges Infusorie-fauna.
+      Lunds Univ. Ärsskrift, II, IV, VI.
+
+SAND, R. 1901. Etude monographique sur le groupe des Infusoires
+      tentaculifères. Ann. d. la Soc. belge de microscopie, XXIV,
+      XXV, XXVI.
+
+SCHAUDINN, F. '95. Die Heliozoen. Das Tierreich, 1895.
+
+SCHEWIAKOFF, W. '89. Beiträge z. Kenntniss der Holotrichen Ciliaten.
+      Bib. Zool., V, p. 1.
+
+---- '93. Ueber einige ecto- u. ento-parasitische Protozoen der
+      Cyclopiden. Bull. Soc. nat. Moscou, 1893. I.
+
+SCHUETT, F. '95. Die Peridineen d. Plankton-Expedition, 1. Kiel u.
+      Leipzig.
+
+SCHULTZE, F. E. '74; 75. Rhizopodenstudien. Arch. f. mik. Anat., X,
+      XI, XIII.
+
+SCHULTZE, M.  '62. Ueber d. Organismus d. Polythalamien. Leipzig,
+      1862.
+
+SHEVYAKOV ?. '96. Monograph on _Holotrichous ciliates_. (In Russian.)
+      Mem. of the St. Petersburg Acad., VII.
+
+STEIN, F. '59; '78; '83. Der Organismus der Infusionsthiere. I.
+      Infusoria, '59; II. Infusoria, '78; III. Flagellata, '83.
+
+---- '49. Untersuchung über die Entwicklungs d. Infusorien. Arch. f.
+      Natur., I, p. 92.
+
+---- '54. Die Infusionsthiere auf ihre Entwicklungsgeschichte
+      untersucht. Leipzig, 1854.
+
+---- '60. Ueber _Leucophrys patula_ u. über 2 neue
+      Infusoriengattungen Gyrocoris u. Lophomonas. Sitz. Ber. d.
+      K.-böhm. Ges. d. Wiss. d. Prag, 1860, p. 4.
+
+---- '64. Ueber die neue Gattung Epiclintes. Id., 1864, I.
+
+STERKI, V. '78. Beiträge z. Morphologie der Oxytrichinen.  Zeit.
+      wiss. Zool., XXXI, p. 29.
+
+---- '98. On the classification of ciliate Infusoria. Amer. Natur.,
+      XXXII, p. 425.
+
+STEVENS, N. M. 1901. Studies on ciliate Infusoria.  Proc. Calif.
+      Acad. Sciences, III, 1.
+
+STOKES, A. C. '84. Notices of some new parasitic Infusoria. Amer.
+      Nat., XVIII, p. 1081.
+
+---- '85. Some apparently undescribed Infusoria from fresh water.
+      Id., XIX, p. 18.
+
+---- '87. Some new hypotrichous Infusoria from American fresh waters.
+      Ann. Mag. Nat. Hist. (5), 20.
+
+TATEM, T. G. '67. New species of microscopic animals.  Q. J. M. S.
+      (n.s.), VII, p. 251.
+
+VEJDOWSKY, F. '79. Monographie der Enchytraeiden.  Prag, 1869.
+
+WALLENGREN, H. '94. Studier ofver ciliata Infusorier, 1. Slagtet
+      Lichnophora. Lund, 1894.
+
+WALLICH, G. C. '63. Observations on an undescribed indigenous Amoeba.
+      Ann. Mag. Nat. Hist. (3), XI, XII.
+
+WESTON, J. '56. On the _Actinophrys sol_. Q. J. M. S., IV, p. 116.
+
+WRZESNIOWSKI A. '61. Observations sur quelques Infusoires. Ann. d.
+      sc. nat. zool. (6), XVI.
+
+---- '69. Ein Beitrag zur Anatomie der Infusorien. Arch. f. mik.
+      Anat., V, p. 25.
+
+---- '70. Beobachtungen über Infusorien a. d. Umgebung v. Warschau.
+      Zeit. wiss. Zool., XX, p. 467.
+
+
+
+***END OF THE PROJECT GUTENBERG EBOOK MARINE PROTOZOA FROM WOODS HOLE***
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diff --git a/old/18320.txt b/old/18320.txt
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--- /dev/null
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+The Project Gutenberg eBook, Marine Protozoa from Woods Hole, by Gary N.
+Galkins
+
+
+This eBook is for the use of anyone anywhere at no cost and with
+almost no restrictions whatsoever.  You may copy it, give it away or
+re-use it under the terms of the Project Gutenberg License included
+with this eBook or online at www.gutenberg.org
+
+
+
+
+
+Title: Marine Protozoa from Woods Hole
+       Bulletin of the United States Fish Commission 21:415-468, 1901
+
+
+Author: Gary N. Galkins
+
+
+
+Release Date: May 5, 2006  [eBook #18320]
+
+Language: English
+
+Character set encoding: ISO-646-US (US-ASCII)
+
+
+***START OF THE PROJECT GUTENBERG EBOOK MARINE PROTOZOA FROM WOODS HOLE***
+
+
+E-text prepared by Ronald Calvin Huber, while serving as Penobscot Bay
+Watch, Rockland, Maine, and Joseph E. Loewenstein, M.D.
+
+
+
+Note: Project Gutenberg also has an HTML version of this
+      file which includes the original illustrations.
+      See 18320-h.htm or 18320-h.zip:
+      (https://www.gutenberg.org/dirs/1/8/3/2/18320/18320-h/18320-h.htm)
+      or
+      (https://www.gutenberg.org/dirs/1/8/3/2/18320/18320-h.zip)
+
+
+
+
+
+Contributions from the Biological Laboratory of the U. S. Fish
+Commission, Woods Hole, Massachusetts.
+
+MARINE PROTOZOA FROM WOODS HOLE.
+
+by
+
+GARY N. GALKINS,
+Department of Zoology, Columbia University.
+
+_Bulletin of the United States Fish Commission_ 21:415-468, 1901
+
+
+
+
+
+
+Comparatively little has been done in this country upon marine
+Protozoa. A few observations have been made by Kellicott, Stokes, and
+Peck, but these have not been at all complete. With the exception of
+Miss Stevens's excellent description of species of _Lichnophora_ I
+am aware of no single papers on individual forms. Peck ('93 and '95)
+clearly stated the economic position of marine Protozoa as sources of
+food, and I need not add to his arguments. It is of interest to know
+the actual species of various groups in any locality and to compare
+them with European forms. The present contribution is only the
+beginning of a series upon the marine Protozoa at Woods Hole, and
+the species here enumerated are those which were found with the algae
+along the edge of the floating wharf in front of the Fish Commission
+building and within a space of about 20 feet. Many of them were
+observed in the water and algae taken fresh from the sea; others
+were found only after the water had been allowed to stand for a few
+days in the laboratory. The tow-net was not used, the free surface
+Protozoa were not studied, nor was the dredge called into play. Both
+of these means of collecting promise excellent results, and at some
+future time I hope to take advantage of them.
+
+My observations cover a period of two months, from the 1st of July
+to the 1st of September. During that time I was able to study and
+describe 72 species representing 55 genera, all from the limited
+space mentioned above. In addition to these there are a few genera
+and species upon which I have insufficient notes, and these I shall
+reserve until opportunity comes to study them further.
+
+I take this opportunity to express my thanks to Dr. Hugh M. Smith
+for many favors shown me while at Woods Hole.
+
+In dealing with these marine forms from the systematic standpoint,
+two courses are open to the investigator. He may make numerous new
+species based upon minor differences in structure, or he may extend
+previous descriptions until they are elastic enough to cover the
+variations. The great majority of marine protozoa have been described
+from European waters, and the descriptions are usually not elastic
+enough to embrace the forms found at Woods Hole. I have chosen,
+however, to hold to the conservative plan of systematic work, and to
+make as few new species as possible, extending the older descriptions
+to include the new forms.
+
+The different classes of Protozoa, and orders within the classes,
+are distributed more or less in zones. Thus the Infusoria, including
+the Ciliata and the Suctoria, are usually littoral in their habitat,
+living upon the shore-dwelling, or attached, water plants and upon
+the animals frequenting them. It is to be expected, therefore,
+that in forms here considered there should be a preponderance of
+Infusoria. Flagellated forms are also found in similar localities,
+but on the Surface of the sea as well; hence the number described
+in these pages is probably only a small proportion of the total
+number of Mastigophora in this region. The Sarcodina, including the
+Foraminifera and the Radiolaria, are typically deep-sea forms and
+would not be represented by many types in the restricted locality
+examined at Woods Hole. Two species, _Gromia lagenoides_ and
+_Truncatulina lobatula_, alone represent the great order of
+Foraminifera, while the still larger group of Radiolaria is not
+represented at all.
+
+The Protozoa described are distributed among the different orders as
+follows:*
+
+
+Class SARCODINA.
+   Subclass RHIZOPODA.
+      Order AMOEBIDA.
+            1. _Amoeba guttula_ Duj
+            2. _Amoeba_ sp.
+            3. _Trichosphaerium sieboldi_ Schn.
+      Order RETICULARIIDA.
+         Suborder IMPERFORINA.
+            4. _Gromia lagenoides_ Gruber.
+         Suborder PERFORINA.
+            5. _Truncatulina lobatula_ Walker & Jacob.
+   Subclass HELIOZOA.
+      Order APHROTHORACIDA.
+            6. _Actinophrys sol_ Ehr.
+      Order CHLAMYDOPHORIDA.
+            7. _Heterophrys myriapoda_ Archer.
+Class MASTIGOPHORA.
+   Subclass FLAGELLIDIA.
+      Order MONADIDA.
+            8. _Mastigamoeba simplex_, n. sp.
+            9. _Codonoeca gracilis_, n. sp.
+           10. _Monas_ sp.
+      Order CHOANOFLAGELLIDA.
+           11. _Monosiga ovata_ S. Kent.
+           12. _Monosiga fusiformis_ S. Kent.
+           13. _Codonosiga botrytis_ (Ehr.) J. Cl.
+      Order HETEROMASTIGIDA.
+           14. _Bodo globosus_ Stein.
+           15. _Bodo caudatus_ (Duj.) Stein.
+           16. _Oxyrrhis marina_ Duj.
+      Order EUGLENIDA.
+           17. _Astasia contorta_ Duj.
+           18. _Anisonema vitrea_ Duj.
+      Order SILICOFLAGELLIDA.
+           19. _Distephanus speculum_ Stoehr.
+   Subclass DINOFLAGELLIDIA.
+      Order ADINIDA.
+           20. _Exuviaella lima_ Clenk.
+           21. _Exuviaella marina_ Clenk.
+      Order DINIFERIDA.
+           22. _Gymnodinium gracile_ Bergh.
+           23. _Glenodinium cinctum_ Ehr.
+           24. _Glenodinium compressa_, n. sp.
+           25. _Peridinium digitale_ Pouchet.
+           26. _Peridinium divergens_ Ehr.
+           27. _Ceratium tripos_ Nitsch.
+           28. _Ceratium fusus_ Ehr.
+           29. _Amphidinium operculatum_ Clap. & Lach.
+Class INFUSORIA.
+   Subclass CILIATA.
+      Order HOLOTRICHIDA.
+         Family ENCHELINIDAE.
+           30. _Lacrymaria lagenula_ Cl. & Lach.
+           31. _Lacrymaria coronata_ Cl. & Lach.
+           32. _Trachelocerca phoenicopterus_ Cohn.
+           33. _Tiarina fusus_ Cl. & Lach.
+           34. _Mesodinium cinctum_, n. sp.
+         Family TRACHYLINIDAE.
+           35. _Lionotus fasciola_ Ehr.
+           36. _Loxophyllum setigerum_ Quenn.
+         Family CHLAMYDODONTIDAE.
+           37. _Nassula microstoma_ Cohn.
+           38. _Chilodon cucullulus_ Muell.
+           39. _Dysteria lanceolata_ Cl. & Lach.
+         Family CHILIFERIDAE.
+           40. _Frontonia leucas_ Ehr.
+           41. _Colpidium colpoda_ Ehr.
+           42. _Uronema marina_ Duj.
+         Family PLEURONEMIDAE.
+           43. _Pleuronema chrysalis_ Ehr.
+           44. _Pleuronema setigera_, n. sp.
+           45. _Lembus infusionum_, n. sp.
+           46. _Lembus pusillus_ Quenn.
+         Family OPALINIDAE.
+           47. _Anoplophrya branchiarum_ Stein.
+      Order HETEROTRICHIDA.
+         Family BURSARIDAE.
+           48. _Condylostoma patens_ Muell.
+         Family HALTERIDAE.
+           49. _Strombidium caudatum_ From.
+         Family TINTINNIDAE.
+           50. _Tintinnopsis beroidea_ Stein.
+           51. _Tintinnopsis davidoffi_ Daday.
+      Order HYPOTRICHIDA.
+         Family PERITROMIDAE.
+           52. _Peritromus emmae_ Stein.
+         Family OXYTRICHIDAE.
+           53. _Epiclintes radiosa_ Quenn.
+           54. _Amphisia kessleri_ Wrzes.
+         Family EUPLOTIDAE.
+           55. _Euplotes charon_ Ehr.
+           56. _Euplotes harpa_ Stein.
+           57. _Diophrys appendiculatus_ Stein.
+           58. _Uronychia setigera_, n. sp.
+           59. _Aspidisca hexeris_ Quenn.
+           60. _Aspidisca polystyla_ Stein.
+      Order PERITRICHIDA.
+         Family LICHNOPHORIDAE.
+           61. _Lichnophora macfarlandi_ Stevens.
+         Family VORTICELLIDAE.
+           62. _Vorticella marina_ Greeff.
+           63. _Vorticella patellina_ Mueller.
+           64. _Zoothamnium elegans_ D'Udek.
+           65. _Cothurnia crystallina_ Ehr.
+           66. _Cothurnia nodosa_ Cl. & Lach.
+           67. _Cothurnia imberbis_ Ehr.
+   Subclass SUCTORIA.
+         Family PODOPHRYIDAE.
+           68. _Podophrya gracilis_, n. sp.
+           69. _Ephelota coronata_ Wright.
+         Family ACINETIDAE.
+           70. _Acineta divisa_ Fraip.
+           71. _Acineta tuberosa_ Ehr.
+         Family DENDROSOMIDAE.
+           72. _Trichophrya salparum_ Entz.
+
+* This classification includes only the orders and families
+  represented at Woods Hole
+
+
+
+Genus AMOEBA Auct.
+
+The pseudopodia are lobose, sometimes absent, the body then
+progressing by a flowing movement; the body consists of ectoplasm and
+endoplasm, the latter being granular and internal, the former hyaline
+and external. There is always one nucleus and one vacuole, but both
+may be more numerous. Reproduction takes place by division or by
+spore-formation. Fresh-water and marine.
+
+
+Amoeba guttala Duj.  Fig. 1.
+
+A minute form without pseudopodial processes, extremely hyaline in
+appearance, and characterized by rapid flowing in one direction.
+The body is club-shape and moves with the swollen end in advance.
+A comparatively small number of large granules are found in the
+swollen portion, while the smaller posterior end is quite hyaline.
+Contractile vacuole absent, and a nucleus was not seen.  Frequent in
+decomposing vegetable matter. Length 37 mu. Traverses a distance of
+160 mu in one minute.
+
+The fresh-water form of _A. guttula_ has a vacuole, otherwise
+Dujardin's description agrees perfectly with the Woods Hole forms.
+
+
+[Illustration: Fig. 1.--_Amoeba guttala_.]
+
+
+Amoeba?  Fig. 2.
+
+A more sluggish form than the preceding, distinguished by its larger
+size, its dense granulation, and by short, rounded pseudopodia,
+which, as in _Amoeba proteus_, may come from any part of the body.
+A delicate layer of ectoplasm surrounds the granular endoplasm, and
+pseudopodia formation is eruptive, beginning with the accumulation
+of ectoplasm. Movement rapid, usually in one direction, but may be
+backwards or sideways, etc. Contractile vacuole absent; the nucleus
+is spherical and contains many large chromatin granules. Length 80 mu;
+diameter 56 mu.
+
+
+[Illustration: Fig. 2.--_Amoeba_ sp.]
+
+
+Genus TRICHOSPHAERIUM Schneider '78
+
+Synonym: _Pachymyxa hystrix_ Gruber.
+
+Marine rhizopods, globular or irregular in form, and slow to change
+shape. Dimorphic. Both forms multinucleate during vegetative life.
+Pseudopodia are long, thin, and thread-form, with rounded ends.
+Their function is neither food-getting nor locomotion, but probably
+tasting. The plasm of both forms is inclosed in a soft gelatinous
+membrane. In one form the jelly is impregnated with needles of
+magnesium carbonate (Schaudinn), but these are absent in the other
+form. The membrane is perforated by clearly defined and permanent
+holes for the exit of the pseudopodia. Reproduction occurs by
+division, by budding or by fragmentation, but the parts are
+invariably multinucleate. At the end of vegetative life the
+needle-bearing form fragments into numerous mononucleate parts; these
+develop into adults similar to the parent, but without the spines.
+At the end of its vegetative life this new individual fragments into
+biflagellated swarm-spores which may conjugate, reproducing the form
+with needles. Size up to 2 mm.
+
+
+Trichosphaerium sieboldi Schneider.  Fig. 3.
+
+With the characters of the genus. A form which I have taken to be a
+young stage of this interesting rhizopod is described as follows:
+
+A minute, almost quiescent, form which changes its contour very
+slowly. The membrane is cap-like and extends over the dome-shaped
+body, fitting the latter closely. The  endoplasm is granular and
+contains foreign food-bodies. Nucleus single, spherical, and
+centrally located. Pseudopodia short and finger-form, emerging from
+the edge of the mantle-opening and swaying slowly from side to side
+or quiescent. The most characteristic feature is the presence of a
+broad, creeping sole, membranous in nature and hyaline in appearance.
+This membrane is the only evidence of ectoplasm, and it frequently
+shows folds and wrinkles, while its contour slowly changes with
+movements of body. The pseudopodia emerge from the body between this
+membrane and the shell margin. Contractile vacuole absent. Length
+42 mu, width 35 mu. In decomposing seaweeds, etc.
+
+Only one specimen of this interesting form was seen, and I hesitate
+somewhat in placing it on such a meager basis. It is so peculiar,
+however, that attention should be called to it in the hope of getting
+further light upon its structure and mode of life. Its membranous
+disk recalls the genus _Plakopus_; its mononucleate condition, its
+membranous disk, and the short, sometimes branched, pseudopodia
+make it difficult to identify with any phase in the life-history of
+_Trichosphaerium_. I shall leave it here provisionally, with the hope
+that it may be found more abundantly another time.
+
+
+[Illustration: Fig. 3.--_Trichosphaerium sieboldi_]
+
+
+Genus GROMIA Dujardin '35.
+
+(Dujardin 1835; M. Schultze '62; F. E. Schultze '74; Leidy '77;
+Buetschli '83; Gruber '84.)
+
+The form is ovoid or globular, and the body is covered by a tightly
+fitting, plastic, chitin shell, which, in turn, is covered by a fine
+layer of protoplasm. The flexibility of the shell makes the form
+variable as in the amoeboid types. The thickness of the shell is
+quite variable. The pseudopodial opening is single and terminal. The
+pseudopodia are very fine, reticulate, granular, and sharply pointed,
+and form a loose network outside of the shell opening. Nucleus single
+or multiple. Contractile vacuole is usually absent. Fresh and salt
+water.
+
+
+Gromia lagenoides Gruber '84.  Fig. 4.
+
+This species is not uncommon about Woods Hole, where it is found upon
+the branches of various types of algae. The body is pyriform, with the
+shell opening at the larger end. The chitinous shell is hyaline and
+plastic to a slight extent, so that the body is capable of some
+change in shape. The shell is thin and turned inwards at the
+mouth-opening, forming a tube (seen in optical section in fig. 4)
+through which the protoplasm passes to the outside. The walls of this
+tube are thicker than the rest of the shell, and in optical section
+the effect is that of two hyaline bars extending into the body
+protoplasm. A thin layer of protoplasm surrounds the shell and
+fine, branching, pseudopodia are given off in every direction. The
+protoplasm becomes massed outside of the mouth-opening and from here
+a dense network of pseudopodia forms a trap for diatoms and smaller
+Protozoa. The nucleus is spherical and contains one or two large
+karyosomes. The protoplasm is densely and evenly granular, without
+regional differentiation. I have never observed an external layer of
+foreign particles, such as Gruber described in the original species.
+
+Length of shell 245 mu; largest diameter 125 mu.
+
+
+[Illustration: Fig. 4.--_Gromia lagenoides_.]
+
+
+Genus TRUNCATULINA D'Orbigny.
+
+A group of extremely variable foraminifera in which the shell is
+rotaline; i. e., involute on the lower side and revolute on the upper
+(Brady). The shell is calcareous and coarsely porous in older forms.
+The characters are very inconstant, and Brady gives up the attempt to
+distinguish the group by precise and constant characters.
+
+
+Truncatulina lobatula Walker & Jacob.
+
+Synonyms: See Brady '84 for a long list.
+
+"It is impossible to define by any precise characters the
+morphological range of the present species. Its variations are
+infinite." (Brady, p. 660.)
+
+This very common form, which occurs in all latitudes, was found
+frequently among the algae at Woods Hole. Its characters are so
+difficult to define that for the present I shall limit my record to
+this brief notice. Size of shell 230 mu by 270 mu.
+
+
+Genus ACTINOPHRYS Ehr.
+
+
+The body is spherical and differentiated into granular endoplasm and
+vacuolated ectoplasm, but the zones are not definitely separated.
+There is one central nucleus and usually one contractile vacuole. The
+pseudopodia have axial filaments that can be traced to the periphery
+of the nucleus.  Fresh and salt water.
+
+Actinophrys sol Ehr., variety.  Fig. 5.
+
+Synonyms: See Schaudinn '95.
+
+The diameter is about 50 mu; the vacuolated ectoplasm passes gradually
+into the granular endoplasm. This is the characterization given _A.
+sol_ by Schaudinn, and it applies perfectly to the freshwater forms.
+If I am correct, however, in placing an _Actinophrys_-like form
+found at Woods Hole in this species, the description will have to
+be somewhat modified. In this form (fig. 5) there is no distinction
+between ectoplasm and endoplasm, and there is an entire absence of
+vacuoles. The nucleus is central, and axial filaments were not seen.
+The single specimen that I found looked much like a Suctorian of
+the genus _Sphaerophrya_, but the absence of a firm cuticle and the
+presence of food-taking pseudopodia with granule-streaming makes it a
+very questionable Suctorian, and 1 place it here until further study
+throws more light upon it.
+
+Diameter of body 40 mu; length of pseudopodia 120 to 140 mu.
+
+
+[Illustration: Fig. 5.--_Actinophrys sol_.]
+
+
+
+Genus HETEROPHRYS Archer.
+
+The body is globular with but slight differentiation into ectoplasm
+and endoplasm; one nucleus in the latter; contractile vacuoles
+one or many; pseudopodia on all sides, thin, and with peripheral
+granule-streaming; surrounded by a globular, rather thick coat of
+jelly, which is hyaline inside and granular on the periphery. Fresh
+and salt water.
+
+
+Heterophrys myriapoda Archer.  Fig. 6.
+
+Synonym: _H. marina_ Hert. & Less. '74.
+
+Diameter 25 to 80 mu; pseudopodia twice as long as the body diameter;
+the plasm often contains chlorophyll bodies (Zoochlorella). The
+granular part of the gelatinous layer is thick (up to 10 mu). The
+spine-like processes are very thin and short. (Schaudinn '95.) The
+marine form found at Woods Hole probably belongs to this species,
+as described by Schaudinn. The short pseudopodia which give to
+the periphery a fringed appearance are quite regularly placed in
+connection with the pseudopodia. The latter are not so long as twice
+the body diameter, the longest being not more than equal to the
+diameter of the sphere. The body inside of the gelatinous covering
+is thickly coated with bright yellow cells similar to those
+on Radiolaria. The animal moves slowly along with a rolling
+motion similar to that described by Penard '90, in the case of
+_Acanthocystis_. Diameter of entire globe 35 mu; of the body without
+the jelly 18 mu. The extremely fine granular pseudopodia are 8 to 35 mu
+long. Common among algae.
+
+This form was probably meant by Peck '95, when be figured "a
+heliozooen."
+
+
+[Illustration: Fig. 6.--_Heterophrys myriapoda_.]
+
+
+KEY TO ORDERS OF FLAGELLIDIA.
+
+Small, body usually amoeboid; 1 or more   Order MONADIDA.
+flagella; no mouth
+
+Small; plasmic collar around the          Order CHOANOFLAGELLIDA.
+flagellum
+
+With 2 or more flagella; one trails       Order HETEROMASTIGIDA.
+behind
+
+With 3 or more flagella, none of which    Order POLYMASTIGIDA.
+trails
+
+Large; firm body wall; 1 or 2 flagella;   Order EUGLENIDA.
+mouth or pharynx, or both
+
+Medium size; with chlorophyll,            Order PHYTOFLAGELLIDA.
+no mouth, usually colonial
+
+Small; silicious skeleton; parasitic      Order SILICOFLAGELLIDA.
+on Radiolaria or free                     (One genus,
+                                          _Distephanus_ Stoehr)
+
+
+KEY TO THE FAMILIES OF MONADIDA.
+
+No mouth; 1 or 2 flagella: amoeboid       Family _Rhizomastigidae_
+with lobose or ray-like pseudopodia
+
+Mouth at base of single flagellum;        Family _Cercomonadidae_
+plastic; no pseudopodia
+
+One flagellum; inclosed in gelatinous     Family _Codonoecidae_
+or membranous cups
+
+One flagellum; tentacle like process      Family _Bikoecidae_
+at base of flagellum; inclosed in cup
+
+One main flagellum and 1 or 2             Family _Heteromonadidae_
+accessory flagella
+
+
+KEY TO MARINE GENERA OF MONADIDA.*
+
+Family _Rhizomastigidae_:
+
+   1. Flagellum repeatedly thrown off     Genus *_Mastigamoeba_
+      and reassumed                       in part
+
+   2. Flagellum never thrown off          3
+
+   3. a. Pseudopodia lobose               Genus _Mastigamoeba_
+
+      b. Pseudopodia ray-like             Genus _Mastigophrys_
+
+Family _Codonoecidae_:
+
+   1. Goblet-shaped cups adherent         Genus *_Codonoeca_
+      by stalk
+
+Family _Heteromonadidae_:
+
+   1. The long flagellum vibratory        Genus *_Monas_
+
+   2. The long flagellum rigid;           Genus _Sterromonas_
+      shorter one vibrates
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE QENERA OF CHOANOFLAGELLIDA.
+
+   1. Without gelatinous                  3
+      or membranous test
+
+   2. With gelatinous                     4
+   or membranous test
+
+   3. a. Attached forms:
+
+         1. Without a stalk, or with      Genus *_Monosiga_
+            a very short one
+
+         2. With a long, simple, stalk    Genus *_Codonosiga_
+
+         3. With a long, branched, stalk  Genus _Codonocladium_
+
+      b. Free-swimming                    Genus _Desmarella_
+
+   4. Colonial, and with a gelatinous     Genus _Proterospongia_
+      covering
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO FAMILIES AND MARINE GENERA OF HETEROMASTIGIDA.
+
+   1. Two flagella nearly equal in size   Family _Bodonidae_
+
+      One main and 2 accessory flagella   Family _Trimastigidae_
+
+Family _Bodonidae_:
+
+   1. Body very plastic,                  Genus *_Bodo_
+      almost amoeboid
+
+      Body not plastic; with large        Genus *_Oxyrrhis_
+      anterior cavity, holding flagella
+
+Family _Trimastigidae_:
+
+   1. With an undulatory membrane         Genus _Trimastix_
+      between accessory flagella
+
+      Without such membrane; flagella     Genus _Costia_
+      contained in a ventral groove
+      while at rest
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF POLYMASTIGIDA.
+
+   1. Body flattened; ends rounded;       Genus _Trepomonas_
+      sides hollowed; often with
+      wing-like processes; cross
+      section S-shaped
+
+   2. Body pyriform; one large            Genus _Tetramitus_
+      asymmetrical groove; 4 flagella
+
+   3. Body spherical; many flagella       Genus _Multicilia_
+      equally distributed
+
+
+KEY TO FAMILIES AND MARINE GENERA OF EUGLENIDA.
+
+   1. With deeply-insunk pharynx;         2
+      no mouth
+
+      With pharynx and distinct mouth     Family _Peranemidae_
+
+   2. Body plastic; usually with          Family _Euglenidae_
+      chromatophores and eye-spot
+
+      Body plastic; no chromatophores;    Family _Astastidae_
+      no eye-spot
+
+Family _Euglenidae_:
+
+      Body _Euglena_-like, inclosed       Genus _Trachelomonas_
+      in shell with round opening for
+      exit of flagellum
+
+Family _Astastidae_:
+
+      Body with one flagellum             Genus *_Astasia_
+
+Family _Peranemidae_:
+
+   1. Body striped; plastic;              Genus _Heteronema_
+      two diverse flagella
+
+   2. Body striped; not plastic;          Genus *_Anisonema_
+      posterior flagellum longer
+      than the other
+
+   3. Body striped; not plastic;          Genus _Entosiphon_
+      with rod-like organ in pharynx
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus MASTIGAMOEBA F. E. Schultze '75.
+
+(Kent '81; Buetschli '86; Klebs '92; Senn 1900.)
+
+In general the form is oval and either regular in outline or
+irregular through the presence of many pseudopodia. One flagellum
+usually quite large and distinct. Differentiation of ectoplasm and
+endoplasm distinct or wanting. One to several contractile vacuoles.
+The pseudopodia are occasionally withdrawn, and the flagellum is the
+sole means of locomotion. In some cases the flagellum turns into a
+pseudopodium, and, conversely, the pseudopodium at one end may become
+a flagellum (see below). In some rare cases the ectoplasm secretes a
+gelatinous mantle. Reproduction not observed.
+
+Fresh and salt water.
+
+
+Mastigamoeba simplex, n. sp.  Fig. 7.
+
+A very small form, first seen in the flagellated stage, aroused my
+interest by reason of the fact that its flagellum lost its regular
+outline and became amoeboid, turning to a pseudopodium, while at the
+same time other pseudopodia were protruded from different parts of
+the periphery. In this condition ectoplasm and endoplasm could be
+made out with the clearest definition. After the pseudopodia were
+well formed, the body became flat and closely attached to the glass
+slide. In a short time one of the pseudopodia became longer than the
+rest; the body became more swollen; the pseudopodia were gradually
+drawn in, with the exception of the more elongate one; this became
+active in movement and finer in diameter, until ultimately it formed
+a single flagellum at the anterior of a small monadiform flagellate.
+The process was repeated two or three times under my observation,
+so that I am convinced that it was not a developmental form of
+some rhizopod. Several of them were seen at different times during
+the summer, and they were always of the same size and form in
+the flagellated or amoeboid condition. I did not make out their
+reproduction, and I shall not be satisfied that this is a good
+species until their life history is known.
+
+In decaying algae. Length 10 mu.
+
+
+[Illustration: Fig. 7.--_Mastigamoeba simplex_.]
+
+
+Genus CODONOECA James Clark '66.
+
+(Kent '81.)
+
+Small forms inclosed in cup or "house" of ovoid or goblet shape,
+colorless and probably gelatinous (chitin?) in texture, and borne
+upon a stalk. The monad does not completely fill the test.
+Contractile vacuole single, posterior.
+
+
+Codonoeca gracilis, n. sp.  Fig. 8.
+
+The cup is urn-shaped with a well-defined neck or collar borne upon a
+shoulder-like end of the body. It is hyaline, colorless, and carried
+upon a stalk equal in length to the cup or shorter than this. The
+animal does not fill the cup, nor is it attached by a filament to
+the latter. There is a single flagellum. The nucleus is minute and
+lateral in position; the contractile vacuole is in the posterior end
+of the body. Total length of cup and stalk 21 mu; of cup alone 12 mu.
+This minute form looked so much like a choanoflagellate that I
+supposed it to be one until I discovered an empty case (Fig. 8).
+
+
+[Illustration: Fig. 8.--_Codonoecea gracilis_.]
+
+
+
+Genus MONAS (Ehr.) Stein '78
+
+(Kent '81; Buetschli '86; Klebs '97; Senn 1900.)
+
+The body is small, globular or oval and either free-swimming or
+fastened by one of the two flagella. The body is sometimes a little
+amoeboid, with short pseudopodial processes. In addition to the main
+flagellum, there are usually one or two small flagella at the basis
+of the larger one.  The nucleus is usually anterior, and one or two
+contractile vacuoles are present.
+
+
+Monas sp.  Fig. 9.
+
+An extremely small form (3 mu) attached by a thread of
+protoplasm--perhaps a flagellum, to algae. The body is ovoid and
+the main flagellum is about four times the length of the body. The
+contractile vacuole is posterior. Only one specimen was seen and
+upon this I shall not attempt to name the species.
+
+
+[Illustration: Fig. 9.--_Monas_ sp.]
+
+
+Genus MONOSIGA Kent '81.
+
+(Buetschli '86; France '97; Senn 1900.)
+
+Small colorless forms of Choanoflagellida, always naked and solitary.
+The posterior end is attached directly to the substratum, or
+there is a short stalk not exceeding the body in length. Kent '81
+distinguished nine species, but Buetschli questioned the accuracy
+of many of these, and in this he was followed by France '97, who
+recognized three species--_Monosiga ovata_, _M. fusiformis_, and _M.
+augustata_. Fresh and salt water.
+
+
+Monosiga ovata S. Kent '81.  Fig. 10.
+
+Synonyms: _M. brevipes_ S. K.; _M. consociata_ S. K.; _M. limnobia_
+Stokes.
+
+The individuals are unstalked or provided with a very short stalk
+less than the body in length. The form is spherical or ovate,
+broadest at the base and tapering to the extremity. The collar is
+somewhat variable in size. In the Woods Hole forms it was about
+the length of the body. Oil particles present. Contractile vacuole
+posterior, nucleus anterior.
+
+Fresh and salt water. Length of body without the collar 5 mu.
+
+
+[Illustration: Fig.10.--_Monosiga ovata_.]
+
+
+Monosiga fusiformis S. K.  Fig. 11.
+
+Synonyms: _M. steinii_ S. K.; _M. longicollis_ S. K.
+
+The individuals are unstalked, minute, and of a general flask-shape.
+The body is swollen centrally and tapers slightly at each end. There
+is no stalk, the body being fixed by the attenuate posterior end.
+There are two contractile vacuoles and one nucleus, which is situated
+a little above the body center. Fresh and salt water. Length without
+collar 9 mu; length of collar 3 mu.
+
+
+[Illustration: Fig. 11.--_M. fusiformis_.]
+
+
+Genus CODONOSIGA (Jas. Clark '67).
+
+(Buetschli '78; Kent '81; France '97; Senn 1900.)
+
+This genus, as modified by France, is distinguished from the
+preceding by the possession of an unbranched stalk much longer than
+the body length. The body is naked and of various shapes, and the
+individuals are solitary or colonial upon a single stalk. Kent '81
+enumerates no less than 10 species, which were cut down by Buetschli
+to 1. France admits 4--_C. botrytis_ Jas. Clark; _C. grossularia_;
+_C. pyriformis_, and _C. furcata_, all S. Kent--but regards the
+second and third as merely form varieties of the first.
+
+
+Codonosiga botrytis (Ehr. sp.) Jas. Clark '67.  Fig. 12.
+
+France gives the following synonyms: _Epistylia botrytis_ Ehr.;
+_E. digitalis_ Stein, _Zoothamnium parasitica_ Stein; _Anthophysa
+solitaria_ Fresenius; _Codonosiga pulcherrima_ Jas. Clark; _Monosiga
+gracilis_ S. Kent; _M. globulosa_ S. Kent; _Codonosiga pyriformis_
+Kent; _C. grossularia_ Kent; (France).
+
+The individuals are small and provided with a long unbranched, or
+terminal, simply split stalk. The individuals are single or colonial.
+The Woods Hole form measured 22 mu over all; the body was 5 mu, the
+collar 3 mu, and the stalk 14 mu. No colonies were seen, and only a few
+individuals upon red algae.
+
+
+[Illustration: Fig. 12.--_Codonosiga botrytis_.]
+
+
+Genus BODO (Ehr.) Stein.
+
+(Stein '59, Buetschli '83; Klebs '92; Senn 1900.)
+
+The body is naked, usually amoeboid in its changes, and provided with
+two flagella, one of which is usually trailed along under and behind
+the animal. The anterior end is usually pointed, with the flagella
+arising from a minute depression; the posterior end is rounded.
+Specific characters very difficult to analyze. Fresh and salt water.
+
+
+Bodo globosus Stein.  Fig. 13.
+
+The body during movement is globular or ovoid, without any anterior
+process. The trailing flagellum is invariably much longer than the
+vibratory one. The contractile vacuole lies in the anterior half of
+the body. Solid food particles are taken in near base of flagella.
+
+Length of body 9 to 12 mu; diameter 8 to 11 mu. Common.
+
+
+[Illustration: Fig. 13.--_Bodo globosus_.]
+
+
+Bodo caudatus (Duj.) Stein.  Fig. 14.
+
+Synonyms: _Amphimonas caudatus_ Duj.; _Diptomastix caudata_ Kent.
+
+The body is variable in shape, but usually flattened and pointed
+posteriorly. An anterior process is almost always present, and
+below this the flagella are inserted in a minute depression. The
+contractile vacuole is close to the base of the flagella. The
+flagella are about the same size, the anterior one usually somewhat
+longer. Common. Length 12 to 18 mu.
+
+This species was seen by Peck '95 and described as a small
+flagellate.
+
+
+[Illustration: Fig. 14.--_Bodo caudatus_.]
+
+
+Genus OXYRRHIS Duj.
+
+(Kent '81; Buetschli '86; Klebs '92; Senn 1900.)
+
+Medium-sized forms, somewhat oval in shape, with a rounded posterior
+end. The anterior end is continued dorsally in a somewhat attenuate
+pointed process. At the base of this process is a large cavity or
+funnel, on the dorsal wall of which, or on a projection from this
+wall, are two equal-size flagella. When at rest, the flagella are
+directed backwards. The nucleus is central. In moving, the posterior
+end is invariably in advance. This genus is exceptional among
+Mastigophora in that division is transverse instead of longitudinal.
+
+
+Oxyrrhis marina Duj.  Fig. 15.
+
+With the characters of the genus. Contractile vacuole not seen.
+Length 28 to 40 mu.
+
+
+[Illustration: Fig. 15.--_Oxyrrhis marina_.]
+
+
+Genus ASTASIA Ehr.
+
+Flagellates with one flagellum, a spindle-form body and a high
+degree of plasticity, the contour constantly changing. A distinct,
+usually striped cuticle is invariably present. "Eye-spots" are
+absent. Fresh and salt water.
+
+
+Astasia contorta Duj.  Fig. 16.
+
+_Astasia inflata_ Duj. '41.
+
+The body is colorless, transparent, and flexible. It is largest in
+the center, thence tapering at the two extremities. The surface of
+the cuticle is obliquely striated, giving to the animal a distinctly
+twisted appearance. The contractile vacuole is in the anterior
+neck-like portion of the body. The flagellum is inserted in a
+distinct oesophageal tube, into which the contractile vacuole
+empties. This tube is continued into a deeper pharyngeal apparatus of
+unknown function.
+
+Common in decaying algae. Length 60 mu; greatest diameter 30 mu.
+
+
+[Illustration: Fig. 16.--Two aspects of _Astasia contorta_.]
+
+
+Genus ANISONEMA Buetschli
+
+Flagellates with two flagella, of which one is directed forwards and
+is concerned with the locomotion of the animal, while the other is
+directed backwards and drags after the animal when in motion. Body
+slightly compressed dorso-ventrally (fig. 17, section). An oral
+furrow is present on the ventral side and the two flagella originate
+in it (fig. 17, at left). The vacuole is on the left side. Food
+vacuoles are present in the posterior part. The nucleus is central.
+Movement creeping.
+
+Fresh and salt water.
+
+
+Anisonema vitrea (Duj.)  Fig. 17.
+
+Synonyms: _Tropidoscyphus octocostatus_ Stein '83; _Sphenomonas_ Kent
+'81; _Ploeotia vitrea_ Senn 1900.
+
+With the characteristics of the genus. It differs from freshwater
+forms in having eight furrowed surfaces running somewhat spirally
+from the posterior to the oral end. Length 50 mu; width 23 mu.  This
+attractive flagellate was quite common in decaying algae at Woods
+Hole; its shaking movement, its peculiar furrowed surfaces, and,
+above all, its perfectly transparent, vitreous appearance, were well
+described by Dujardin. Stein's _Tropidoscyphus octocostatus_ is a
+fresh-water form which may possibly be a distinct species, especially
+as it is described with both flagella directed forwards.
+
+
+[Illustration: Fig. 17.--_Anisonema vitrea_.]
+
+
+Genus DISTEPHANUS  Stoehr.
+
+An aberrant flagellate bearing a single flagellum and a silicious
+skeleton resembling those of the Radiolaria. The skeleton consists
+of two rings of different diameter parallel with one another and
+connected by silicious bars. From the wider ring half a dozen bars
+radiate outwards and a similar number of short thorn-like bars point
+inwards obliquely. The color is yellow, and except for the flagellum
+the form might easily be mistaken for a Radiolarian, as has been the
+case repeatedly.
+
+
+Distephanus speculum Stoehr.
+
+_Dictyocha speculum_ Stoehr; _Dictyocha_ Auc.
+
+With the characters of the genus.
+
+A single specimen only of this very interesting form was seen at
+Woods Hole. It occurred in a collection of tow made near the end of
+the wharf during the evening.
+
+
+KEY TO FAMILIES OF DINOFLAGELLIDIA.
+
+   1. No crossfurrow; two free flagella   Family _Prorocentridae_
+
+   2. One or more cross-furrows           3
+
+   3. Cross-furrow nearly central         Family _Peridinidae_
+      (cf. _Oxytoxum_)
+
+      Cross-furrow close to               Family _Dinophysidae_
+      anterior end
+
+      Several cross-furrows               Family _Polydinidae_
+      and flagella                        (One genus, _Polykrikos_.)
+
+
+KEY TO MARINE GENERA OF PROROCENTRIDAE.
+
+Diagnostic characters: The transverse furrow is absent and the two
+flagella arise from the anterior end of the body. The shell may be
+bivalved.
+
+   1. No tooth-like process dorsal        Genus *_Exuviaella_
+      to the flagellum
+
+   2. With tooth-like process dorsal      Genus _Prorocentrum_
+      to the flagellum
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF PERIDINIDAE.
+
+Diagnostic characters: The cross-furrow is nearly central (see,
+however, _Oxytoxum_); the body may or may not have a shell; the
+shell may or may not be composed of distinct plates; the plates are
+distinguished as _equatorial_ (_i.e._, bordering the cross-furrow),
+_apical_, and _antapical_, while still another, the "rhombic plate",
+may be present, extending from the cross-furrow to the apex.
+
+   1. Without distinct shell              Genus *_Gymnodinium_
+
+      With a distinct shell               2
+
+   2. Shell not composed of definite      3
+      plates
+
+      Shell composed of definite plates   4
+
+   3. Cross-furrow replaced by            Genus _Ptychodiscus_
+      thin-skinned band
+
+      Cross-furrow well defined;          Genus _Protoceratium_
+      reticulate markings raised
+      on shell-surface
+
+      Cross-furrow well defined;          Genus *_Glenodinium_
+      no markings
+
+   4. Two parts of shell equal or         5
+      nearly equal
+
+      Two parts of shell very unequal     11
+
+   5. With transverse flagellum in        6
+      a distinct furrow
+
+      Transverse flagellum not in a       10
+      furrow
+
+   6. With horns, or with wing-like       7
+      processes
+
+      Without processes of any kind       9
+
+   7. Processes small, wing-like,         Genus _Diplopsalis_
+      around flagellum-fissure
+
+      Processes horn-like                 8
+
+   8. Anterior part with 7 equatorial     Genus *_Peridinium_
+      and 1 rhombic plates
+
+      Anterior part with 5 equatorial     Genus _Gonyaulax_
+      and no rhombic plates
+
+      Anterior part with 3 equatorial     Genus *_Ceratium_
+      and no rhombic plates
+
+   9. Anterior part with 14 equatorial    Genus _Pyrophacus_
+      and 1 rhombic plates
+
+      Anterior part with 7 equatorial     Genus _Goniodoma_
+      plates
+
+      Anterior part with 4 equatorial     Genus _Amphidoma_
+      plates
+
+  10. Apical extremity drawn out          Genus _Podolampas_
+      into a tube
+
+      Apical extremity not drawn out      Genus _Blepharocysta_
+      into a tube
+
+  11. Cross-furrow deep, with great       Genus _Ceratocorys_
+      ledge-like walls
+
+
+      Cross-furrow wide, no ledge-like    Genus _Oxytoxum_
+      walls
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO MARINE GENERA OF DINOPHYSIDAE.
+
+Diagnostic characters: The cross-furrow is above the center of the
+body, and its edges, as well as the left edge of the longitudinal
+furrow, are usually produced into characteristic ledges; those of
+the cross-furrow usually form great funnel-like anterior processes,
+while those of the longitudinal furrow usually form great, lateral,
+wing-like processes ornamented by ribs and other markings.
+
+   1. Without shell; longitudinal         Genus *_Amphidinium_
+      furrow may open & close
+
+   2. With shell; longitudinal furrow     3
+      unchangeable
+
+   3. With distinct apical funnel         4
+
+      No apical funnel                    Genus _Phalacroma_
+
+   4. With great wing-like ledge          5
+
+      Ledges very small; body long,       Genus _Amphisolenia_
+      needle-like
+
+   5. Ledge of longitudinal furrow        6
+      extends to posterior end
+
+      Ledge of longitudinal furrow        Genus _Dinophysis_
+      does not extend to posterior end
+      (Recorded by Peck ('93-'95) as very abundant at Woods Hole
+      and in Buzzards Bay.)
+
+   6. Ledge is continued dorsally to      Genus _Ornithocercus_
+      the cross-furrow
+
+      Ledge is not continued dorsally     7
+
+   7. With deep dorsal cavity;            Genus _Citharistes_
+      secondary funnel not notched
+
+      No dorsal cavity; secondary         Genus _Histioneis_
+      funnel deeply notched
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EXUVIAELLA Cienkowsky '82.
+
+(Klebs '81; Pouchet '83, '86.)
+
+The form varies from globular to ovoid, with occasionally a sharp
+posterior end. Shells are usually somewhat compressed, and consist
+of two valves, which frequently slide one over the other in such a
+manner as to show the structure with great clearness. The right shell
+may have a distinct indentation in the anterior edge. There are two
+lateral, discoid, brown chromatophores, each of which possesses a
+central amylum granule. The nucleus is posterior. Salt water.
+
+
+Exuviaella lima Ehr.  Fig. 18.
+
+Synonyms _Pyxidicula_ Ehr.; _Cryptomonas_ Ehr.; _Prorocentrum lima_
+Kent; _Amphidinium_ Pouchet.
+
+The shell is ovate, rounded and swollen posteriorly. The anterior
+border of both shells is slightly indented. The shell is quite thick.
+The animal moves through the water very slowly. Dark brown in color.
+Length 48 mu; width 44 mu.
+
+
+[Illustration: Fig. 18.--_Exuviaella lima_.]
+
+
+Exuviaella marina Cienkowsky.  Fig. 19.
+
+A smaller form than the preceding, more elliptical in outline, with
+a thinner shell and with large granules throughout the endoplasm.
+The nucleus is spherical and subcentral in position and possesses a
+distinct central granule. This may be a small variety of _E. lima_.
+
+
+[Illustration: Fig. 19.--_Exuviaella marina_.]
+
+
+Genus GYMNODINIUM Stein '78.
+
+(Bergh '81; Kent '81; Pouchet '83, '85; Entz '84; Schuett '95.)
+
+The general structure of these forms is similar to that of
+_Glenodinium_; the most striking and positive difference is the
+absence of a shell. The animals are, as a rule, spherical, yet they
+may be pointed at the two ends or at one of them. They are also
+frequently flattened dorso-ventrally. The transverse furrow may
+be either circular and straight around the body or may describe a
+spiral course, passing even twice around the body. The flagella
+arise near cross-furrow or, in some cases, in longitudinal furrow.
+Chromatophores may or may not be present and food-taking is holozoic,
+in many cases at least. In some cases ectoplasm and endoplasm can be
+distinguished. Fresh and salt water.
+
+
+Gymnodinium gracile Bergh '82, var. sphaerica, n.  Fig. 20.
+
+The body is divided by the transverse furrow into a shorter anterior
+and a longer posterior part. The longitudinal furrow is broader at
+the posterior extremity than at the cross-furrow. The structural
+feature upon which this new variety is made is the unvarying
+plumpness of the body, making it almost spherical, except for
+a slight flattening dorso-ventrally. The nucleus is large and
+ellipsoidal, with characteristic longitudinal markings of chromatin.
+The endoplasm is evenly granular, with a number of large ingested
+food bodies. The color is brown, not rose-red as in Bergh's species,
+nor is the Woods Hole form as large as the latter. Length of body
+68 mu; width 55 mu. Common.
+
+
+[Illustration: Fig. 20.--_Gymnodinium gracile_, var. _sphaerica_.]
+
+
+Genus GLENODINIUM (Ehr.), Stein '83.
+
+(Bergh '82; Buetschli '86; Pouchet '85; Daday '86.)
+
+Small globular forms with two distinct furrows, one transverse around
+the body, the other longitudinal upon the face only. The shell is
+soft and structureless with a distinct aperture near the meeting
+point of the two furrows. The endoplasm usually, but not always,
+contains a bright red eye-spot.
+
+Fresh and salt water.
+
+
+Glenodinium compressa, n. sp.  Fig. 21, a, b, c.
+
+This species resembles _G. acuminata_ of Ehrenberg except that it is
+strongly compressed laterally. The longitudinal furrow extends nearly
+to the extremity of the animal. It begins as a narrow slit and widens
+as it progresses upon the left side; it also becomes much deeper
+on this side and at the bottom of the depression the longitudinal
+flagellum is inserted. The transverse furrow runs evenly around the
+body near the upper pole, giving to the shell almost the aspect of
+an _Amphidinium_. Brown chromatophores may or may not be arranged
+radially about a central amylum granule. One striking characteristic
+is the depth of the two furrows. The nucleus is elongate and somewhat
+curved; it lies against the posterior wall of the rather thick shell.
+Not uncommon.
+
+Length 40 mu; breadth 32 mu; width 18 mu.
+
+The posterior end of the animal is often somewhat pointed and this
+point frequently becomes attached, so that the animal whirls around
+upon it as upon a pivot.
+
+
+[Illustration: Fig. 21 a, b, c.--_Glenodinium compressa_, n. sp.]
+
+
+Glenodinium cinctum Ehr.  Fig. 22.
+
+The body is globular, smooth, and homogeneous.  Brown chromatophores
+arranged radially, each in the form of a cone, the base of which
+rests against the shell while the points turn inward.  A bright-red
+eye-spot may or may not be present; when present it is placed near
+the junction of the two furrows. The longitudinal furrow is small.
+Fresh water and salt.
+
+Length and diameter the same, 21 mu.
+
+This species was observed by Peck '93.
+
+
+[Illustration: Fig. 22.--_Glenodinium cinctum_.]
+
+
+Genus PERIDINIUM Ehr. '32, Stein '83.
+
+(Claparede & Lachmann '58; Bergh '81; Pouchet '83; '85; Gourret '88;
+Buetschli '86.)
+
+The form is globular, ovoid or elongate, the apex frequently drawn
+out into a long tube. The transverse and longitudinal furrows are
+quite distinct, the former having often a spiral course about the
+body. The two halves of the body are similar, the posterior being
+somewhat shorter; the anterior half has seven equatorial plates, an
+oral plate, two lateral apical plates, and one or two dorsal plates.
+The two antapical plates frequently have a tooth-like process. The
+bodies are colorless, green or brown.
+
+Fresh and salt water.
+
+
+Peridinium digitale Pouchet.  Fig. 23.
+
+Synonyms: _Protoperidinium digitale_ Pouchet; _Protoperidinium_ Bergh
+p. p.; _P. divergens_ Peck.
+
+The shell is covered with pits of large size. The posterior part
+is hemispherical and surmounted by a single horn or spine. The
+transverse furrow is very oblique, and its two extremities are united
+by a sigmoid longitudinal furrow. The anterior half bears two spines
+or horns of different size, and variable.  The nucleus is spherical
+or ellipsoidal and placed in the posterior half of the shell.
+
+Length 68 mu; diameter 54 mu. Common.
+
+Although the description of Pouchet's _P. digitale_ differs in some
+respects from a careful description of the Woods Hole form, I think
+the species are the same. The chief difference is in the single horn
+of the posterior half; in Pouchet's form this is furrowed by a narrow
+groove which runs to the S-shaped longitudinal furrow. In the Woods
+Hole form I was unable to make out such a furrow. The flagella, also,
+were not seen. This same form was pictured by Peck '95 as _P.
+divergens_.
+
+
+[Illustration: Fig. 23.--_Peridinium digitale_.]
+
+
+Peridinium divergens Ehr.  Fig. 24.
+
+Synonym: _Ceratium divergens_ Kent.
+
+The shell is spheroidal, widest centrally, attenuate and pointed
+posteriorly; the anterior portion is armed with two short, pointed
+horns, each of them having a toothed process at the basal portion
+of the inner margin. They are frequently colorless and beautifully
+transparent, the body being free from large opaque granules; again
+they are colored brown or yellow. The nucleus is large and elongate
+and finely granular. 75 mu long and 68 mu in diameter. Common.
+
+
+[Illustration: Fig. 24.--Ventral and dorsal aspects of _Peridinium
+divergens_.]
+
+
+Genus CERATIUM (Schrank).
+
+(Stein '78; Perty '52; Clap & Lach. '58; Bergh '82; Pouchet '83;
+Gourret & Roeser '88; Buetschli '85; Kent '81; Senn 1900; Schuett '98.)
+
+The general shape is a flattened sphere with three long processes
+or horns. The cross-furrow is either spiral or circular; the
+longitudinal furrow is usually wide and occupies the greater part of
+the anterior half of the shell. The shell is thick, reticulate or
+striped, and sometimes provided with short spines; often distinctly
+porous. The anterior half is composed of 3 equatorial and 3 apical
+plates, the latter being continued into the horn-like process. The
+posterior half is composed of 3 equatorial and one apical plate
+continued into the posterior horn. The right posterior plate is
+continued into a similar horn which may remain rudimentary or be
+continued into a considerable process. Similarly the left posterior
+horn is usually developed, but remains small. There may be from 2 to
+3, 4, and 5 horns. Chromatophores usually present, green to yellow
+brown.
+
+Fresh and salt water.
+
+
+Ceratium tripos Ehr.  Fig. 25.
+
+The body is somewhat triangular and bears three horns, two of which
+are shorter than the other one and slightly curved upward.
+
+Length, including the horns, 290 mu.
+
+
+[Illustration: Fig. 25.--_Ceratium tripos_.]
+
+
+Ceratium fusus Ehr.  Fig. 26.
+
+Synonym: _Peridinium fusus_ Ehr.
+
+The animal is very elongate, due to the presence of two long horns
+at the extremities of the body. Color, yellow with chromatophores.
+Length 285 mu; width 23 mu.
+
+Both of these species are common in the tow and in the algae at the
+edge of the wharf. Both of them are mentioned by Peck in '93 and '95.
+
+
+[Illustration: Fig. 26.--_Ceratium fusus_.]
+
+
+Genus AMPHIDINIUM Clap. & Lach.
+
+The body is ovoid to globular and usually much flattened
+dorso-ventrally. The anterior portion is very much reduced and is
+somewhat head-like or cap-like. The longitudinal furrow extends
+through the entire posterior body length and is apparently capable
+of widening and narrowing. It is probably naked (see here Klebs,
+Pouchet, Buetschli), although Stein maintained that there is a
+delicate cuticle-like shell. Chromatophores of brown or green colors
+present and usually grouped radially about a central amylum granule.
+The nucleus is posterior.
+
+Fresh and salt water.
+
+
+Amphidinium operculatum Clap. & Lach.  Fig. 27.
+
+The body is oval and flattened. The transverse furrow is at the
+extremity (posterior) of the body and the small portion, which is
+thus apparently cut off, is the cap-like or operculum-like structure
+which gives the name to the species. Klebs maintains that the two
+furrows are not connected, but in this he is certainly mistaken,
+provided we have the same species under consideration.  Very common
+about Woods Hole.
+
+Length from 40 to 50 mu; width 30 mu; thickness 15 mu.
+
+
+[Illustration: Fig. 27.--_Amphidinium operculatum_.]
+
+
+
+KEY TO INFUSORIA.
+
+1. With cilia                             Subclass _Ciliata_. 3
+
+2. Without cilia (in adult state)         Subclass _Suctoria_
+   tentacles
+
+3. a. Without a specialized fringe of     Order _Holotrichida_
+      large cilia (ad. zone)
+
+   b. With general covering of cilia      Order _Heterotrichida_
+      + adoral zone
+
+   c. With cilia on ventral side          Order _Hypotrichida_
+      + adoral zone
+
+   d. With cilia in region of adoral      Order _Peritrichida_
+      zone, and about mouth only
+
+
+KEY TO FAMILIES OF THE HOLOTRICHIDA.
+
+A. Mouth closed except during food        1
+   ingestion; no undulating membrane
+
+   Mouth always open; with undulating     2
+   membrane
+
+   1. _Gymnostomina_.
+
+      a. Mouth terminal or subterminal.   Family _Enchelinidae_
+         Food is swallowed and not
+         introduced by currents
+
+      b. Mouth terminal or subterminal;   Family _Trachelinidae_
+         body frequently drawn out into
+         long process; mouth may have
+         specialized framework.
+
+      c. Mouth central or posterior;      Family _Chlamydodontidae_
+         pharynx with supporting
+         framework
+
+   2. _Trichostomina_.
+
+      a. Mouth anterior or central;       Family _Chiliferidae_
+         pharynx short or absent;
+         peristomial depression faint
+         or absent
+
+      b. Mouth central; pharynx long,     Family _Urocentridae_
+         tubular; cilia in two broad
+         zones
+
+      c. Mouth posterior; form            Family _Microthoracidae_
+         asymmetrical; cilia dispersed
+         or limited to oral region
+
+      d. Mouth anterior or central.       _Paramoecidae_
+         Peristomial depression           (One genus, _Paramoecium_)
+         clearly marked.
+
+      e. Mouth at end of long peristome   Family _Pleuronemidae_
+         running along ventral side;
+         body dorso-ventrally or
+         laterally compressed; left edge
+         of peristome with great, sail-
+         like undulating membrane
+
+      f. Mouth and pharynx distinct,      Family _Isotrichidae_
+         posterior; cilia uniform.
+         Parasites in ruminants.
+
+      g. Mouth absent; body vermiform,    Family _Opalinidae_
+         cilia uniform. Usually
+         parasites.
+
+
+KEY TO MARINE GENERA OF ENCHELINIDAE
+
+Diagnostic characters: Form ellipsoid or ovoid; the mouth is
+invariably terminal and is usually round--more rarely slit-formed; it
+is closed except when food is taken. An oesophagus when present is a
+short, invariably non-ciliated tube which is usually surrounded by
+a more or less clearly defined buccal armature. The anus is usually
+terminal. Large food particles are swallowed, never introduced by
+currents.
+
+   1. Body naked                          3
+
+   2. Body inclosed in a shell or coat    7
+
+   3. a. Cilia uniform about the entire   4
+         body; body symmetrical
+
+      b. Cilia in the mouth region        5
+         longer than the others; body
+         symmetrical
+
+      c. Bristles, or tentacles, in       6
+         addition to cilia
+
+   4. Mouth terminal; body ellipsoidal    Genus _Holophrya_
+      to ovoid
+
+   5. a. Mouth terminal; body elongate,   Genus _Chaenia_
+         flexible, and elastic
+
+      b. Mouth terminal; "neck" highly    Genus *_Lacrymaria_
+         elastic; entire body
+         flexible; conical "head"
+
+      c. Mouth terminal; "neck" highly    Genus *_Trachelocerca_
+         elastic; entire body
+         flexible; "head" square
+
+      d. Mouth terminal; "neck" highly    Genus _Lagynus_
+         elastic; no separate
+         mouth-bearing portion
+
+   6. a. Body asymmetrical; bristles      Genus _Stephanopogon_
+         in addition to cilia
+
+      b. Body symmetrical; 4 small        Genus *_Mesodinium_
+         tentacles from mouth; cilia
+         and cirri in girdles
+
+   7. Shell composed of small             Genus *_Tiarina_
+      sculptured pieces; cilia long,
+      uniform
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LACRYMARIA Ehr. '30.
+
+(Ehrenberg, C. G., 1838; Perty '52; Claparede & Lachmann '58; Stein
+59-83; Quennerstedt '66, '67; Fromentel '74; Kent '81; Gruber '84;
+Gourret & Roeser '86; Buetschli '88; Schewiakoff '89.)
+
+Body short to very long flask-shape; for the most part contractile,
+especially in the neck region. The posterior end is rounded or
+pointed. The main character is the mouth-bearing apex, which "sets
+like a cork in the neck of the flask." One or more circles of long
+cilia at the base of the mouth portion or upon it. The body is
+spirally striped. Contractile vacuole terminal, with sometimes one
+or two further forward. Macronucleus central, globular to elongate,
+sometimes double. Food mainly bacteria. Fresh and salt water.
+
+
+Lacrymaria lagenula Clap. & Lach.  Fig. 28, a, b.
+
+Synonym: _L. tenuicula_ Fromentel '74.
+
+Body more or less flask-shape, two or three times as long as broad,
+with conical apex, which is slightly elastic and protrusible; surface
+obliquely striate, with well-defined lines, 14 to 16 in number; cilia
+uniform on the body, with a crown of longer ones at the base of the
+conical proboscis. The body cilia are not thickly placed except
+around the proboscis. The endoplasm is thickly packed with large
+granules (food particles) in the anterior half and with finely
+granular particles in the posterior half. The elongate macronucleus
+lies a little above the center among the larger granules; the
+contractile vacuole is double, one on each side of the median line
+and at the posterior end of the body among the finer granules. The
+anus is posterior. Length 90 mu to 160 mu; greatest width assumed 65 mu.
+When fully expanded the posterior end assumes a curious polyhedral
+form. (Fig. 28 b.)
+
+This form differs slightly from others of the same species as
+described by different observers, the most striking difference being
+the presence of two contractile vacuoles in place of the usual one.
+These are very slow to fill and grow to a large size before diastole.
+The membrane is very tough and retains its form easily under pressure
+of the cover glass. Another characteristic feature is the flattening
+of the surfaces between the striae. Decaying algae.
+
+
+[Illustration: Fig. 28.--_Lacrymaria lagenula_.]
+
+
+Lacrymaria coronata Cl. & Lach. '58.  Fig. 29.
+
+Synonyms: _L. lagenula_ Cohn '66; Moebius '88; _L. cohnii_ ? Kent '81;
+_L. versatilis_ Quen. '67.
+
+Form flask-like and similar to _L. lagenula_, contractile but tough.
+The contractile vacuole is terminal, the proboscis is short, slightly
+raised and separated from the body by a deep cleft; the buccal cilia
+are inserted part way up on the proboscis. Form changeable, from
+short, sac-like to elongate and vermiform. Length 85 mu.
+
+This species is not very different from _L. lagenula_, but I noted
+that in addition to the elongate nucleus, the body striae are much
+more apparent here and seem to sink into the cuticle, giving the
+periphery, especially at the collar region, a curious crenulated
+effect. The endoplasm is very densely granular and colored a
+blue-green, probably from food particles. The number of striae is much
+larger than in the preceding species. The membrane is very tough and
+retains the shape of the body, even with the full pressure of the
+cover glass. Micronucleus and trichocysts were not observed.
+
+
+[Illustration: Fig. 29.--_Lacrymaria coronata_.]
+
+
+Genus TRACHELOCERCA (Ehr. '83) Cohn '66.
+
+(Quennerstedt '67; Gruber '87; Entz '84; Kent '81; Gourret & Roeser
+'88; Buetschli '88; Schewiakoff '89; Shevyakov '96.)
+
+The only well-known representative is very elongate, large (up
+to 3 mm. Van Beneden), and very contractile. The main feature of
+importance in distinguishing it is the 4-part structure of the mouth
+region, which, however, may not be obvious. Pharynx faint and smooth.
+Contractile vacuole terminal. Macronucleus in one central body or in
+numerous pieces scattered throughout the cell.  Salt water.
+
+
+Trachelocerca phoenicopterus Cohn '66.  Fig. 30.
+
+Synonyms: _T. sagitta_ Ehr. '40, Stein '59; _T. tenuicollis_
+Quennerstedt '67, Kent '81; _T. minor_ Gruber '87, Shevyakov '96.
+
+The body is extremely elongate and ribbon-like, and this, combined
+with its wonderful power of extension and retraction, makes it one of
+the most curious and interesting of microscopic forms. The anterior
+end is square or cylindrical; the type species has a four-sided
+mouth, but many specimens may be found which have a plain cylindrical
+mouth region. One reason for this may be the fact that the extremity
+gets broken off. In one instance I noticed a very large form with the
+anterior end under some debris, which evidently held it tight, for
+the body of the ciliate was thrashing back and forth and twisting
+itself into knots, etc., like a nematode worm. Finally, the anterior
+end broke off with about one-tenth of the body; the remainder, in an
+hour, had regenerated a new anterior end with long cilia, but with
+no indication of four sides. The small anterior piece was also very
+lively, moving about and eating like the normal animal; its history,
+however; was not followed. This species appears to be variable in
+other ways as well; thus, in some cases the posterior end is rounded
+(cf. Entz '84); in others it is pointed (cf. Kent '81, Cohn '66, et
+al.).
+
+Again, the macronucleus may be a single round body (Entz '84,
+Buetschli '88) or in two parts (Kent '81), or in many parts scattered
+about the body (Gruber). In the Woods Hole forms the tail is
+distinctly pointed and turned back sharply, forming an angle at the
+extremity. The cilia on this angular part are distinctly longer than
+the rest. The function of this posterior part is apparently to anchor
+the animal while it darts here and there upon the tail as a pivot,
+contracting and expanding the while. The body is finely striated
+with longitudinal markings; when contracted there are no transverse
+markings nor annulations. The nucleus is in the form of many
+fragments scattered throughout. Length of large specimen 1.7 mm.
+
+
+[Illustration: Fig. 30.--_Trachelocerca phoenicopterus_.]
+
+
+Genus MESODINIUM Stein '62.
+
+(Maupas '82, '84; Entz '84; Shevyakov '96.)
+
+The main part of the body is globular or conical, with a short,
+platform-like oral region, and a deep annular groove about the
+middle of the body. The oesophagus is rather long, and smooth or
+longitudinally striped. One or more rings of cirri rise in the
+groove. If more than one ring of cirri are present, the anterior set
+usually point forward and lie close to the anterior part of the body.
+The posterior set, on the other hand, cling close to the posterior
+region of the body and give to it a peculiar encapsuled appearance.
+The most characteristic feature is the presence of four short
+tentacle-like processes which can be protracted and retracted from
+the oral region. (Mereschowsky says that the entire anterior half
+is more or less contractile.) The macronucleus is horseshoe-shaped
+or ovoid and is situated in the posterior half of the body. The
+contractile vacuole is also posterior.
+
+Movement consists in rapid swimming, with rotation on its axis, or
+in creeping by means of its anterior cirri, or in sudden jumping, by
+which it apparently clears a distance of 20 times its diameter in one
+bound. Mouth parts may also be used for attachment to foreign bodies.
+The moving periods alternate with quiescent periods, during which the
+organisms with their outstretched and radiating cirri resemble the
+heliozooen _Actinophrys_.
+
+
+Mesodinium cinctum, n. sp.  Fig. 31.
+
+Body spherical to pyriform, constricted near the middle, the
+constriction dividing the body into dissimilar parts. The anterior
+part is broadly pyriform, somewhat plastic and hyaline, with an oral
+extremity which is sometimes hollow, sometimes evaginated and convex.
+Upon this flexible anterior part there are four short but distensible
+tentacles. The posterior part is granular and usually filled with
+food particles; it is well rounded and holds the nucleus and
+contractile vacuole. The entire body is surrounded by a fine cuticle.
+The nucleus is elongate and extends through the greater part of the
+posterior half. The contractile vacuole lies on one side, near the
+girdle. The mouth is on the anterior pole in the tentacle region. The
+motile organs are cirri and cilia, all inserted in the constriction.
+There are two sets of cirri and one of cilia; the latter stand out
+radially from the girdle and are usually in motion. The cirri of
+one set, the anterior, extend forward about twice the length of the
+anterior half; those of the posterior set closely engirdle the lower
+half, reaching not quite to the posterior extremity. These are
+somewhat hyaline and are closely approximated, giving the impression
+of a tight-fitting crenulate casing about the lower half. The cirri
+are sharply pointed, much broader at the base, and the two sets are
+so placed that, looked at from above, they have the appearance of a
+twisted cord. (Fig. 31 b.) Movement erratic; sometimes the animal
+swims steadily forward with mouth in front; again it shoots across
+the field of the microscope, either backward or forward or sideways,
+through the action of its powerful cirri. It is often quiet, usually
+mouth downward, and is held in place by adhesion of the tentacles. In
+this position it looks strikingly like a heliozooen.
+
+Length 35 mu; greatest width 30 mu. Not uncommon.
+
+The chief features by which this species is distinguished from the
+frequently described _M. pulex_ of Europe are the number of anterior
+cirri and the ring of true cilia in place of the central girdle of
+cirri. The European form is described with four anterior bristles;
+the present form has from 28 to 32. The radial cilia differ decidedly
+from the more powerful cirri and they are not in one plane, so that
+counting is difficult; they are not closely set. The presence of
+tentacles makes these forms of especial theoretical interest,
+especially in the light of the origin of _Suctoria_.
+
+
+[Illustration: Fig. 31.--Side and top views of _Mesodinium cinctum_.]
+
+
+Genus TIARINA R. S. Bergh '79.
+
+(Claparede & Lachmann '58.)
+
+Body subcylindrical, pointed posteriorly, two and one-half times
+as long as broad; encased in covering composed of separate pieces
+arranged in five girdles. The pieces bear processes which rest
+against neighboring pieces of the girdle. Mouth large, anus terminal
+near contractile vacuole. The macronucleus is simple and round. Salt
+water.
+
+
+Tiarina fusus (Cl. & Lach.) emend R. S. Bergh.
+
+Synonyms: _Coleps fusus_ Cl. & Lach. '58; Daday '86; Moebius '88,
+Lauterborn '94; Shevyakov '86.
+
+This form, which resembles _Coleps_ rather closely, was placed as a
+separate genus by R. S. Bergh. The skeletal parts consist of five
+zones of needles composed of an organized substance and embedded in
+the cortical plasm, the last zone coming to a point at the posterior
+end. The needles have lateral processes, which give a latticed
+appearance to the casing. The cilia are long, with a specialized
+crown of still longer ones at the oral end; they arise outside of the
+skeletal elements and do not pass between them, as in _Coleps_.
+
+
+KEY TO MARINE GENERA OF TRACHELINIDAE.
+
+Diagnostic characters: Body bilateral, or asymmetrical by local
+prolongations; usually compressed or flattened laterally, the left
+side more convex than the right. The essential feature is the
+position and character of the mouth. This is either a long slit
+extending from the anterior end well down the ventral surface, or the
+posterior part only of a ventral furrow remains open as a round or
+elongate mouth some distance from the anterior end. The entire mouth
+region of the body is usually drawn out into an elongate tapering
+proboscis which is generally curved dorsally at the extremity.
+An oesophagus is short or absent altogether; when present it is
+supported by a stiff buccal armature. Cilia are uniform about entire
+body or limited to the flat right side. Food is swallowed.
+
+1. a. Proboscis easily distinguished      2
+      from the main body
+
+   b. Proboscis not marked off from       Genus *_Loxophyllum_
+      main body; body flat;
+      both surfaces striated
+
+2. a. Mouth runs the entire length        Genus _Amphileptus_
+      of proboscis; entire body
+      uniformly ciliated
+
+   b. Mouth runs the entire length        Genus *_Lionotus_
+      of proboscis; body flat; right
+      side only is ciliated
+
+   c. Proboscis much drawn out,           Genus _Dileptus_
+      flexible; mouth at its base
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LOXOPHYLLUM Dujardin '41.
+
+(Duj. '41; Wrzesniowski '69; Quennerstedt '65; '67; Cohn '66; Entz
+'84; Gourret & Roeser '88; Buetschli '88; Shevyakov '96.)
+
+The body is flat and somewhat leaf-shape, flexible, and elastic. The
+anterior end is somewhat proboscis-like and flexible, but is not
+sharply demarcated as in _Lionotus_. The central portion of the body
+is developed into a more or less arched dorsal mass, which usually
+contains the nuclei and contractile vacuoles. As a result of this
+local thickening, the body is surrounded by a thin hyaline margin.
+This, however, may be absent on the right side in some species. The
+mouth reaches from the anterior extremity to a short distance from
+the end, and usually approaches the left edge. An anus is present
+near the posterior end of the dorsal swelling. Trichocysts are
+numerous on the ventral surface, and often on the dorsal surface,
+where they are inclosed in minute papilla-like swellings.
+Cilia-distribution controverted. Maupas and Buetschli hold that
+ventral surface alone is ciliated; others (Kent and Dujardin) that
+cilia are uniformly distributed. The entire body, dorsal and ventral
+surfaces alike, are uniformly striated. The contractile vacuole lies
+posteriorly, on the right side and in the dorsal swelling. In the
+fresh-water form _L. meleagris_, it is connected with a long canal
+whose swellings are frequently taken for additional contractile
+vesicles (Buetschli); in the marine form described below the canal is
+not developed and a series of vacuoles takes its place; these are
+all contractile. The macronucleus may be single, double, quadruple,
+band-formed, or rosette-formed. Movement is steadily progressive and
+peculiarly gliding. Fresh and salt water.
+
+
+Loxophyllum setigerum Quenn. '67.
+
+Synonyms: _Litosolenus armatus_ Stokes '93; _Litosolenus verrucosa_
+Stokes '93.
+
+The body is flattened, irregular in outline, obtusely pointed
+anteriorly, the point being turned to the right; rounded posteriorly.
+The left edge is nearly straight, the right considerably arched with
+a few setae on the posterior half. Contractile vacuoles are numerous,
+dorsal in position and on the right side. The macronueleus is beaded,
+the several spheres connected.
+
+
+Variety armatum (Cl. & Lach.) Fig. 32.
+
+Under the name _Litosolenus armatus_, Stokes described a form from
+brackish water near New York, which should unquestionably be referred
+to the genus _Loxophyllum_, and I believe to Quennerstedt's species
+_setigerum_. While the latter possesses only a few setae, the former
+has a number of them, and Stokes described his species as having a
+variable number. For this reason I include the Woods Hole form under
+the tentative name _armatum_, as a variety of Quennerstedt's _L.
+setigerum_. The flat margins are distinctly striated longitudinally,
+and faintly marked radially, on the dorsal surface. Longitudinal
+elevated striae also run the length of the dorsal hump and upon the
+entire ventral surface. The ventral surface is alone ciliated. Upon
+the edges of the flat border are sharp-pointed, colorless, spine-like
+processes, situated at equal distances around the entire periphery
+except at the anterior end. Each spine is thick at the base and
+tapers to a full point which is curved upward--_i. e._, dorsally
+(fig. 32, a, b). The entire body is plastic and contractile, turning
+its leaf-like edge readily over objects upon which it creeps. The
+cilia are fine and uniform, with a tendency to lengthen in the oral
+region.
+
+Length 100 mu; greatest width assumed on contraction 85 mu; when normal
+about 50 mu.
+
+
+[Illustration: Fig. 32.--_Loxophyllum setigerum_, var. _armatum_. a,
+b, c, ventral, dorsal, and lateral aspects.]
+
+
+Genus LIONOTUS Wrzesniowski '70.
+
+(Incorrectly called _Litonotus_ by many. Entz '84; Gruber '84;
+Buetschli '88; Kent '81; Schewiakoff '89; Shevyakov '96.)
+
+The body is elongate and somewhat lance-shaped, widest at the central
+part and tapering to a point at the anterior end. The posterior end
+may be similarly tapered or rounded. The anterior end frequently
+proboscis-like, flat, and flexible, while the entire body is more or
+less elastic and contractile.  The right side is flattened and alone
+provided with cilia, while the left side of the body proper is
+arched; on the left side of the proboscis is a row of coarse cilia
+resembling an adoral zone, and a row of trichocysts. A long peristome
+stretches down the thin, ventral side of the proboscis, and the mouth
+proper is situated at the junction of the proboscis and body; the
+mouth, as a rule, is invisible. The ciliated right side alone is
+striated in the majority of species. The contractile vacuole may be
+single or multiple, usually in the posterior region of the body and
+dorsal in position. The macronucleus is usually double, rarely single
+or quadruple, but may occasionally break into numerous smaller
+pieces.  Movement, free-swimming or gliding, with especial tendency
+to get under clumps of foreign matter.
+
+Fresh and salt water.
+
+
+Lionotus fasciola Ehr.  Fig. 33.
+
+Synonyms. _Amphileptus fasciola_ Ehr. '38; Dujardin '41; Lachmann
+          '56;  Cohn '66, Diesing '65.
+          _Loxophyllum fasciola_ Claparede & Lachmann '58;
+          Balbiani '61.
+          _Loxophyllum duplostriatum_ Maupas '83. Shevyakov '96.
+
+Body frequently brown or brilliant yellow in color, somewhat sigmoid
+in form with tapering anterior end, the extremity of which is turned
+dorsally. The proboscis is about half the entire length and is not
+sharply marked from the rest of the body but tapers gradually, its
+base being equal to the diameter of the body at its middle point. The
+body is slightly contractile and the posterior end is carried to a
+rounded point, but not into a distinct tail. Unlike the fresh-water
+variety, this one has no hyaline margin nor hyaline caudal region,
+and the contractile vacuole is double or multiple on the dorsal side
+near the posterior end. Cilia are present only on the under (right)
+side, with, however, a row of large cilia marking the course of the
+elongate mouth, upon its left side. The right side is striated, the
+left arched and without markings. The endoplasm is finely granular
+with, however, larger food particles in the process of digestion,
+while specimens are occasionally seen with the natural form
+completely lost through distortion caused by over-large captures (Cf.
+also Wrzesniowski '70, p. XXIII, fig. 32). Movement continuous, slow,
+and gliding; very little tendency to jerking movements. Macronucleus
+double, both parts spherical, and placed in about the center of the
+larger part of the body; closely approximated but not, as Schewiakoff
+described, connected. In conjugation, a large form unites with a
+smaller one, the mouth parts being connected. Details of conjugation
+and macronuclei not made out. Length 200 mu to 600 mu.
+
+
+[Illustration: Fig. 33.--_Lionotus fasciola_.]
+
+
+KEY TO MARINE GENERA OF CHLAMYDODONTIDAE.
+
+Diagnostic characters: Form usually ellipsoid, never very elongate.
+Transverse section of body circular or elliptical. The mouth is
+usually some distance from the anterior end and may be in the
+posterior part. Sometimes it is in the center of the ventral
+surface, again on the right side. The oesophagus invariably has
+a well-developed buccal armature, or a smooth peculiarly built
+oesophageal tube. Food particles of large size.
+
+1. Body cylindrical. Cilia about          Genus *_Nassula_
+   entire body
+
+   Body flat                              2
+
+2. a. Without a caudal process            3
+
+   b. With a caudal process               5
+
+3. a. Anterior end angular                4
+      on left side
+
+   b. Anterior end rounded                Genus _Chlamydodon_
+
+4. a. Dorsal striae and cilia present,    Genus _Orthodon_
+      ventral cilia longer
+
+   b. Dorsal striae and cilia absent;     Genus *_Chilodon_
+      posterior end not pointed
+
+   c. Dorsal striae and cilia absent;     Genus _Scaphidiodon_
+      posterior end pointed
+
+5. a. Caudal spine with posterior         6
+      bristle-like cilia
+
+   b. Caudal spine without posterior      Genus _Trochilia_
+      bristle-like cilia;
+      ventral cilia reduced
+
+6. a. With pigment spot on anterior       Genus _AEgyria_
+      angle
+
+   b. Without such pigment spot           Genus _Onychodactylus_
+
+   c. Cilia on right edge only of         Genus *_Dysteria_
+      greatly reduced ventral surface
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus NASSULA Ehr. '33
+
+(Dujardin '41; Stein '67; Cienkowsky '55; Cohn '66; Clap. et Lach.
+'58; Kent '81; Maupas '83; Entz '84; Fabre-Domergue '88; Buetschli
+'88; Shevyakov '96.)
+
+The body is ovoid or cylindrical, with well-rounded ends, and in
+some cases slightly flattened. The mouth is ventral and placed some
+distance from anterior end (1/4 to 1/3 total length). A slight
+depression on the ventral surface marks the mouth region, which is
+further indicated by larger and more powerful cilia. The rest of the
+body is uniformly ciliated. The entire body is marked by clearly
+defined spiral stripes. The mouth is circular and the oesophagus is
+supported by a considerable armature, which usually extends dorsally
+and to the left, rarely to the right. In some cases the structure of
+this armature is indistinct; again it can be clearly seen to consist
+of definite rods (Staebchen). The anus is probably always terminal.
+Contractile vacuoles are variable in different species. In some cases
+there is but one, which is placed at the posterior end or centrally
+on the ventral side; in others there may be four--two dorsal and
+two ventral. In many cases trichocysts are uniformly distributed.
+Sometimes the body is colorless; again, and more often, it is
+brightly colored with red, blue, brown, or black pigment. The
+macronucleus is globular and central, occasionally band-form and
+with numerous attached micronuclei. Food substance varied, usually
+vegetable matter, see, however, below. Cysts are globular. Movement
+is a steady progression, combined with rolling.
+
+
+Nassula microstoma Cohn '66.  Fig. 34.
+
+Synonyms: _Paramoecium microstomum_ Cl. et Lach. '58, Gourret et
+Roeser '88; _Isotricha microstomum_ Kent '81.
+
+Body subcylindrical, rounded at each extremity, not quite twice as
+long as broad. A slight depression on one surface marks the position
+of the mouth, this depression being indicated by a row of longer
+cilia. The mouth is extremely small and is surrounded by a curious
+buccal armature. This is not made up of bars or rods, as in most
+species of _Nassula_, but appears perfectly smooth and uniform
+except for the considerable swelling at the inner end. The cuticle is
+firm and unyielding and marked by longitudinal and somewhat spiral
+rows of cilia and trichocysts. Under the microscope this is one of
+the most pleasing forms found at Woods Hole. Its color is yellowish
+brown from the presence of brilliant particles of coloring matter
+held in the cortical plasm, and, as it slowly rolls along, these
+particles and the black trichocysts give to the organism a peculiar
+sparkling effect. The macronucleus is almost central; the contractile
+vacuole posterior. The endoplasm appears well filled with food
+bodies, some of which could be distinguished as _Amphidinium_ and
+_Glenodinium_.
+
+Length 55 mu; greatest diameter 30 mu.
+
+
+[Illustration: Fig. 34.--_Nassula microstoma_.]
+
+
+Genus CHILODON Ehr.
+
+(Dujardin '41; Engelmann '78; Stein '54, '58; Kent '81; Buetschli '88;
+Gruber '83; Cienkowsky '55; Moebius '88; Clap. et Lach '58;
+Wrzesniowksi '65; Shevyakov '96.)
+
+Small forms, greatly flattened dorso-ventrally and almost egg-form in
+outline. The anterior end is bent distinctly to the left and forms a
+characteristic process, which, together with the entire margin of the
+body, is soft and flexible. The posterior end is, as a rule, broadly
+rounded. The ventral surface is finely striate, and this surface
+alone is ciliated. The lines of cilia converge at the mouth, and at
+this region the cilia are somewhat larger and more distinct, thus
+forming a functional adoral zone. The mouth is median and is situated
+in the anterior half of the body. It is surrounded by a well-defined
+armature, composed usually of from 10 to 16 rods. The contractile
+vacuoles are quite varied and from one to many in number, the
+number increasing with the size of the individual. The macronucleus
+is usually single, elliptical in form, and centrally placed;
+one micronucleus. Reddish granular pigment and trichocysts are
+occasionally present.
+
+
+Chilodon cucullulus Muell., sp.  Fig. 35.
+
+Synonyms; _Colpoda cucullus_ O. F. Mueller; _Loxodes cucullulus_;
+_Chilodon uncinatus_ Ehr. '58, Perty '52, Dujardin '41; _L. dentatus_
+Duj., etc.
+
+This extremely variable form has received so many different names
+that it hardly pays to enumerate them. It is one of the commonest
+and most widely spread ciliates known, although at Woods Hole I was
+surprised to see it so rarely. It is the type species of the genus
+and needs no further description. The specimens observed at Woods
+Hole had numerous contractile vacuoles and were 42 to 45 mu long and
+from 28 to 32 mu wide.
+
+
+[Illustration: Fig. 35.--Ventral and dorsal aspects of _Chilodon
+cucullulus_.]
+
+
+Genus DYSTERIA Huxley '57.
+
+(Cl. et Lach. '58; Entz '84; Moebius '88; Shevyakov '96.)
+
+Small forms, firm in outline, and colorless or slightly colored. The
+body is somewhat clam-shaped, flattened, slightly curved or straight
+on the right side, the other more convex. The true ventral side is
+only a narrow strip along the right and anterior edge of the body,
+the apparent ventral side being a fold of the very large dorsal
+surface which comes around ventrally, forming a valved structure
+somewhat analogous to a clam shell. Cilia are limited to the outer
+edge of the small ventral surface, which also bears a peculiar spine
+at the posterior end. Behind this spine are larger cilia. The mouth
+opening lies in the anterior widened portion of the ventral surface
+and is connected with a smooth tubular pharynx. The right half of the
+dorsal side, _i.e._, the apparent dorsal side, is arched and bears
+longitudinal ridges. Two to four contractile vacuoles are placed on
+the ventral side. The macronucleus is usually dorsal, elliptical, and
+cleft, with one micronucleus attached. Fresh and salt water.
+
+
+Dysteria lanceolata Cl. et Lach.  Fig. 36.
+
+Synonym: _Cypridium lanceolatum_ Kent '81.
+
+Outline of the flattened body ovoid; body consists of two valve-like
+portions; the edge of the right valve is nearly straight, that of the
+left valve more or less sinuous; anteriorly it is cut away, obliquely
+and posteriorly it has a deep indentation in which the seizing spine
+rests. The cilia are confined to the ventral surface, here reaching,
+however, from the anterior dorsal extremity to below the posterior
+indentation. Posteriorly the cilia become larger, corresponding to
+the larger cirri of _D. armata_, which are posterior to the spine.
+The mouth lies between the two valves and is surrounded by a long
+and smooth buccal armature which passes downward and backward to
+the left a distance equal to about half the entire body length. The
+macronucleus is situated in the dorsal region in the central part of
+the body. There are two contractile vacuoles, one behind the center
+of the buccal armature, the other near the inner end of this organ.
+Movement is in circles, the animal moving around quite rapidly when
+not attached by its posterior process. It is colorless and measures
+45 mu in length by 27 mu in width. Claparede & Lachmann and Shevyakov
+describe it as 70 mu long.
+
+
+[Illustration: Fig. 36.--_Dysteria lanceolata_.]
+
+
+KEY TO MARINE GENERA OF CHILIFERIDAE.
+
+Diagnostic characters: Mouth never lies behind the middle of the
+body; the oesophagus is but slightly developed. The undulating
+membranes are placed either on the edge of the mouth or in the
+oesophagus. A peristomial depression leading to the mouth is absent
+or very slightly indicated.
+
+1. Mouth in the anterior half,            Genus *_Frontonia_
+   undulating membrane on left edge
+   only; right edge continued in a
+   long ventral furrow
+
+2. Two undulating membranes; mouth        Genus *_Colpidium_
+   central; no caudal bristles
+
+3. Two undulating membranes; caudal       Genus *_Uronema_
+   bristle
+
+
+Genus FRONTONIA Ehr. (Cl. & Lach. '58?).
+
+(Ehrenberg, subgenus of _Bursaria_ '38; Claparede & Lachmann '58;
+Buetschli '88; Shevyakov '96.)
+
+Form elongate and cylindrical, or often flattened dorso-ventrally,
+with round or pointed ends. It is usually plastic and contractile.
+Cilia are evenly distributed about the body and are similar in
+length. The large, open mouth lies on the anterior half of the
+ventral surface, and is elongate and oval in outline. On its left
+edge is a well-defined membrane which stretches across to the right
+side of the mouth. On the right edge is a small, longitudinally
+striped tract which is free from trichocysts and smooth in
+appearance. This tract is continued posteriorly in a long furrow,
+which in some cases reaches the posterior end of the animal. A few
+rows of cilia in this furrow vibrate differently from the others and
+give the effect of a membrane (Buetschli). The oesophagus is extremely
+short and hard to make out. The body is usually covered uniformly
+with trichocysts, often of considerable size. There are 1 or 2
+vacuoles with long canals radiating throughout the endoplasm. The
+macronucleus is oval and centrally placed. Micronuclei vary from
+one to many. An anal opening is placed at the end of the long
+ventral furrow. The plasm is colorless or green by the presence of
+Zoochlorella, or colored brown or black by pigments. In these cases
+there is a considerable pigment mass on the anterior end. Movement
+is regular, forward, and combined with rotation. Food consists of
+foreign objects, diatoms, other protozoa and the like. Fresh and salt
+water.
+
+
+Frontonia leucas Ehr.  Fig. 37.
+
+Synonyms: _Frontonia vernalis_ Ehr. '38; _Bursaria leucas_ Allman
+'55, Carter '56; _Panophrys leucas_ Duj. '41, Stein '67; _Panophrys
+vernalis_ Dujardin '41, Stein '67; _P. chrysalis_ Duj. '41, Fromentel
+'74; _Cyrtostomum leucas_ Stein '67, Kent '81.
+
+Form ovoid, elongate, occasionally a little flattened
+dorso-ventrally. Mouth in the anterior third of the body. The left
+edge of the mouth carries a distinct undulating membrane; the right
+edge is plain, longitudinally striated and bears cilia. It is
+slightly depressed and the depression is carried posteriorly in the
+form of a shallow furrow which reaches to the posterior end. The
+contractile vacuole is on the left side, the spheroidal nucleus on
+the right side of the furrow. The body is uniformly covered with fine
+cilia, and the periphery is uniformly studded with large trichocysts,
+except along the furrow. Food consists of dinoflagellates and other
+small forms. Color dark brown to black.
+
+Length 330 mu; width 200 mu.
+
+This form differs considerably from the fresh-water _Frontonia
+leucas_ as described by Schewiakoff '89, especially in the extreme
+length of the peristomial furrow, in the position of the nucleus and
+contractile vacuole, and in the nature of the water canals. These
+in the Woods Hole form are very irregular in size and very much
+branched, not uniform as in Lieberkuehn's (see Buetschli) figure of
+_Frontonia leucas_, nor radiating as in Schewiakoff's description.
+This may be the same species as _Frontonia marina_, of Fabre-Domergue
+'91, whose description and figure I have not seen.
+
+
+[Illustration: Fig. 37.--_Frontonia Leucas_.]
+
+
+Genus COLPIDIUM Stein '60
+
+(Buetschli '88; Maupas '83.)
+
+The general form is oval, slightly compressed laterally with the
+dorsal side strongly arched. The ventral side is slightly incurved.
+The anterior end is somewhat smaller than the posterior end, which is
+broadly rounded. The mouth is placed some distance from the anterior
+end in an oral depression and opens into a tubular oesophagus. There
+are usually two undulating membranes which do not extend beyond the
+mouth borders. The right undulating membrane extends down into the
+oesophagus and appears to be attached to the walls of the latter. The
+body stripes in front of the mouth are twisted to the left. The anus
+is terminal and the contractile vacuole may be terminal or situated
+forwards in the dorsal region. The macronucleus is spherical and
+has one  micronucleus attached. Food consists mainly of bacteria.
+Movement rapid, but interrupted.
+
+Fresh and salt water, common in infusions.
+
+
+Colpidium colpoda Ehr., sp.  Fig. 38.
+
+Synonyms: _Colpidium cucullus_ Kent '81; _C. striatus_ Stokes '85;
+_Kolpoda cucullus_ Duj. '41; _Paramoecium colpoda_ Ehr. '38,
+Quennerstedt '67; _Plagyiopyla nasula_ Kent '81, G. & R. '86;
+_Glaucoma pyriformis_ G. & R. '86; _Tillina campyla_ Stokes '85, '88.
+
+The body is oval, somewhat larger posteriorly, and a little
+compressed dorso-ventrally. The anterior end is twisted a little from
+the right to the left (more evident in fresh-water forms), and leans
+somewhat toward the ventral side. Under this portion, on the ventral
+side, lies the mouth in a large depression just above the middle of
+the body. The entire body is covered with uniform and delicate cilia,
+which are placed in longitudinal rows. These rows are almost straight
+on the dorsal side, but bend on the ventral surface, following
+the contour of the twisted anterior portion. The endoplasm is
+finely granular; the oesophagus leading into it is very distinct.
+Schewiakoff ('89) describes two membranes, an inner and an outer;
+Maupas ('83) describes them as right and left. In the present species
+I was able to make out only one. The macronucleus is central,
+spherical in form, and bears a single minute micronucleus. The
+contractile vacuole is posterior and dorsal to the long axis of the
+body. The anus is ventral to this axis and also posterior. Length
+45 mu, width 20 mu. Common.
+
+This marine variety is much smaller than the fresh-water form and the
+form differs in a number of respects, viz, in the anterior torsion
+and in the structure of the mouth. These may be, however, only
+individual variations of a widely spread species, and I believe it is
+perfectly safe to describe this as _Colpidium colpoda_.
+
+
+[Illustration: Fig. 38.--_Colpidium colpoda_.]
+
+
+Genus URONEMA Duj. '41.
+
+(Quennerstedt '69; Cohn '66; Kent '81; Buetschli '81; Schewiakoff '89;
+Shevyakov '96.)
+
+Minute forms; colorless and constant in body form. The form is oval,
+slightly compressed on the ventral side, while the dorsal side is
+distinctly arched. The membrane is distinctly marked by rather widely
+separated striae. These occasionally have a spiral course about the
+body; in all cases they can be easily counted. The mouth is large
+and placed near the center of the ventral surface. It is sometimes
+approached by a very shallow depression or peristome from the
+anterior end, and marked by two rows of cilia. An undulating membrane
+extends down the mouth. Oesophagus absent. A long, stiff bristle
+extends outwards from the posterior end. The contractile vacuole is
+terminal or subterminal and near the anal opening. The macronucleus
+is spherical, centrally placed, and with one micronucleus closely
+applied. Movement is rapid and usual forwards in a straight line,
+often found resting, however, with outstretched cilia in contact with
+some foreign body. Food mainly bacteria. Fresh and saltwater, usually
+in decomposing vegetable substances.
+
+
+Uronema marina Duj.  Fig. 39.
+
+Synonyms: _Enchelys triquetra_ Dujardin; _E. corrugata_ Duj.;
+_Cryptochilum griseolum_ Maupas '83; _Philaster digitiformis_
+Fabre-Domergue '85.
+
+Small animals with ellipsoidal form and about twice as long as
+broad. The mouth lies in the upper half of the body and bears a
+well-developed undulating membrane upon its left edge. The membrane
+is longitudinally striped and covered with long and vibratile cilia.
+The right edge of the mouth bears cilia which are about the same in
+size as the body cilia, but are more closely inserted (Schewiakoff).
+The most characteristic feature is the long caudal bristle, which
+is extremely delicate and about two-thirds the length of the body.
+Schewiakoff thinks this bristle has a sensory function. I could not
+make this out, for although other protozoa ran against this bristle,
+often bending it well over to one side, the animal showed no sign
+of irritability but lay quiescent. A spherical macronucleus with
+attached micronucleus lies in the center of the body. The contractile
+vacuole is posterior in front of the bristle. The macronucleus was
+found to be double, as though just divided, in a large percentage of
+cases. This may be a precocious division of the nucleus long before
+signs of the body division are evident. Such a phenomenon, however,
+is rare, the macronucleus usually dividing at a late stage of cell
+division. Length 30 to 50 mu; width 15 to 20 mu. Common in decomposing
+algae.
+
+
+[Illustration: FIG. 39.--_Uronema marina_.]
+
+
+KEY TO MARINE GENERA OF PLEURONEMIDAE.
+
+Diagnostic characters: The mouth is at the end of a long peristome
+running along the ventral side; the body is dorso-ventrally or
+laterally compressed. The entire left edge of the peristome is
+provided with an undulating membrane which occasionally runs around
+the posterior end of the peristome to form a "pocket" leading to
+the mouth. The right edge of the peristome is provided with a
+less-developed membrane. There may or may not be a well-developed
+pharynx.
+
+Body small; not produced into             Genus *_Pleuronema_
+ neck-like elongation
+
+Body medium-sized; anterior end           Genus *_Lembus_
+produced into neck-like elongation
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PLEURONEMA Dujardin '41.
+
+(Perty '52; Clap. & Lach. '58; Stein '59, vol. I; Quennerstedt '67;
+Kent '81; Buetschli '88; Schewiakoff '89; Shevyakov '96.)
+
+Small to medium-sized ciliates, with an unchanging form. They are
+somewhat lens-shape and laterally compressed, the two surfaces
+about equally arched. The ventral surface is nearly straight or
+but slightly arched; the dorsal is quite convex.  The anterior and
+posterior extremities are equally rounded.  The peristome begins as
+a small depression, but becomes larger until it takes in nearly all
+of the ventral surface. The depression becomes much deeper at about
+the center of the body, and is especially marked on the left side of
+the peristome. In this deeper portion is the mouth, with an almost
+imperceptible oesophagus. Upon the left edge of the peristome is a
+high, undulating membrane, sail-like in appearance when extended.
+This may stretch around the posterior edge of the peristome and upon
+the right aide, thus forming a pocket by means of which the food
+particles are directed into the mouth. The rest of the right edge
+of the peristome is occupied by closely approximated powerful cilia
+(Buetschli) or a second undulating membrane (Stein). The body cilia
+are relatively long. Trichocysts and caudal bristles may be present.
+The contractile vacuole is subterminal and dorsal; it is questionable
+whether there are canals leading to it. A round macronucleus with
+one micronucleus is in the anterior half of the body. The anus is
+terminal. Food is chiefly bacteria. Movement combines springing with
+swimming and rotation. Fresh and salt water.
+
+
+Pleuronema chrysalis Ehr., sp.  Fig. 40.
+
+Synonyms: _Pleuronema crassa_ Dujardin '41; _P. marina_ Duj. '41;
+Fabre-Domergue '85; _P. coronata_ Kent '81; _Paramoecium chrysalis_
+Ehr. '38; _Lembadion orale_ G. & R. '88; _Histiobalantium agile_
+Stokes '85, '88.
+
+The body is ovoid, slightly flattened, rounded at both ends, the
+anterior end sharper than the posterior. The ventral surface is
+almost entirely taken up by a peristome which extends from the
+anterior end posteriorly three-quarters of the body length. The
+posterior end of the peristome is straight, the left curved,
+following the depressed portion. The body is covered with fine cilia
+in longitudinal lines, except on the peristome. The mouth is small
+and situated in the hollow of the peristome near the left border. On
+the left peristome edge is a large undulating membrane. It begins
+near the anterior end of the body and increases in height posteriorly
+following the peristome edge around on the right side. This posterior
+bend of the membrane causes the appearance of a full sail, so
+often seen. It can be entirely withdrawn and folded together in
+the peristome. On the right edge of the peristome are large,
+powerful cilia. The contractile vacuole is central and dorsal; the
+macronucleus is in the anterior half of the body, with one attached
+micronucleus. Food consists of bacteria. Not very common. Fresh
+and salt water. It often remains quiet, with membrane and cilia
+outstretched, as though dead, but suddenly gives a spring and is
+gone.
+
+
+[Illustration: Fig. 40.--_Pleuronema chrysalis_.]
+
+
+Pleuronema setigera, n. sp.  Fig. 41.
+
+Body colorless, elongate, and with the general form of a cucumber,
+the posterior end being somewhat pointed. The mouth and relatively
+small peristome are situated in the lower third of the body. The
+peristome begins as a shallow furrow at the center of the ventral
+surface and dips sharply into the buccal depression, which is deep
+and turned toward the posterior end. The left edge of the peristome
+bears a high undulating membrane, which extends anteriorly only
+as far as the center of the body; posteriorly it passes around to
+the right edge of the peristome, thus forming the characteristic
+membranous pocket. Inside the oral depression is a second undulating
+membrane, running down to the mouth. This is small and without an
+oesophagus. The body is clothed with long setose cilia which are
+frequently fully outstretched when the animal is resting, a slight
+tremor of the large membrane alone indicating vitality. Posteriorly
+these appendages are drawn out into long filiform setae, the number
+varying in different individuals from three to nine or ten. These
+are extremely fine and difficult to see without a high power (_e.g._
+1/12 oil) and careful focussing of the substage condensor. Like _P.
+chrysalis_, the resting periods are terminated by sudden springs,
+otherwise the movements are steady and forward. The macronucleus is
+central, and the contractile vacuole posterior and terminal. Length
+45 mu to 50 mu; greatest diameter 17 mu. In decaying algae.
+
+It was this form, I believe, that Peck '95 described as a "ciliate."
+
+
+[Illustration: Fig. 41.--_Pleuronema setigera_.]
+
+
+Genus LEMBUS Cohn '66.
+
+(Cohn '66; Quennerstedt '69; Kent '81; Fabre-Domergue '85; Gourret &
+Roeser '88; Buetschli '88; Shevyakov '96.)
+
+Free-swimming animals of elongate form, more or less elastic, and
+flexible, bending readily to avoid obstacles, etc. The anterior half
+is usually drawn out into a slightly curved neck-like portion. The
+peristome is a small groove leading from the anterior end to the
+mouth about midway down the ventral side of the body. Buetschli,
+following Quennerstedt, describes an undulating membrane on each side
+of the peristome groove. Other observers, however, usually describe
+but one, the left, which is clearly defined and stretches out some
+distance from the body, while the right border is described as having
+smaller but very active cilia. The general body surface is clothed
+with fine, uniform cilia, and body striae are usually absent. One
+or more caudal bristles may be present. The contractile vacuole is
+posterior and terminal, and may be multiple. The macronucleus is
+spherical and perhaps double (Kent). Food is chiefly bacteria, and
+the animals are frequently found with the anterior end embedded in
+zoogloea masses. Salt water, usually in infusions.
+
+
+Lembus infusionum, n. sp. Fig. 42.
+
+The body is elongate, lancet-shaped, with a tapering anterior
+extremity. The dorsal outline is concave through the bending of the
+anterior end, while the ventral outline presents an even, convex
+curve. The mouth lies slightly above the center of the body and marks
+the posterior limit of the ventral peristomial groove, which curves
+slightly from the anterior extremity. Each side of this groove bears
+an undulating membrane, the left being much larger and conspicuously
+striated. The general form of this left membrane is triangular,
+the widest part is anterior, the narrowest at the mouth. The
+right membrane is similar in form, but smaller and more active.
+The endoplasm is colorless and finely granular, not regionally
+differentiated. The ectoplasm consists of a relatively thick cortical
+plasm specially noticeable in the posterior half of the body and
+a delicate cuticle which bears almost imperceptible longitudinal
+markings--the insertion points of the fine cilia. The body is covered
+with uniform cilia except at the anterior extremity. Here they are
+much larger and bristle-like. I was unable to find any cilia in the
+peristome. One long caudal bristle, one-quarter of the length of the
+body, trails out behind. The macronucleus is spheroidal and placed
+near the center of the body; a conspicuous micronucleus lies near it.
+A row of contractile vacuoles extends from the posterior end. I have
+seen as many as six of nearly equal size and one or two smaller ones.
+The intervals of contraction are quite long. Length 70 to 75 mu;
+greatest diameter 10 to 12 mu.
+
+_L. infusionum_ resembles _L. elongatus_ in its general form and in
+its mode of life, for it excavates a retreat in zoogloea masses and
+lies there for considerable periods perfectly quiet. It differs
+from _L. elongatus_ and from _L. velifer_ (probably the same as _L.
+elongatus_ of Claparede & Lachmann) in the presence of the caudal
+bristle, in the absence of annular markings, number of contractile
+vacuoles, and in the slightly smaller size. It resembles _Lembus
+verminus_ (Mueller) as described by Kent (_Proboscella vermina_), and
+_L. intermedius_ as described by Gourret & Roeser (_Lembus verminus_
+syn.)in the absence of annular markings and in the presence of a
+caudal bristle. It differs from the former, however, in the absence
+of a tentacle-like process, and from both in the absence of a double
+nucleus and in the presence of many vacuoles. These features are so
+characteristic of all the specimens examined that I have concluded,
+somewhat reluctantly, to give it a specific name. It is common in old
+infusions of algae, especially after decomposition is well advanced.
+Its food consists of bacteria.
+
+
+[Illustration: Fig. 42.--_Lembus infusionum_.]
+
+
+Lembus pusillus Quennerstedt 1869.  Fig. 43.
+
+Synonym: _L. subulatus_ Kent 81.
+
+This species is much smaller than the preceding, and might easily
+be mistaken for _Uronema marina_. It is subcylindrical in form, the
+anterior end bluntly pointed, the posterior end rounded. The oral
+apparatus is quite different from _Uronema_. The mouth, as in the
+preceding species, is at the end of a long peristomial groove
+extending from the anterior end to the middle of the body. The edges
+of the peristome bear undulating membranes as in _L. infusionum_.
+Like the latter, there is one caudal bristle, but unlike it there is
+only one posterior contractile vacuole, while the endoplasm is filled
+with large granules or food balls. The cuticle is distinctly striated
+with longitudinal markings, and the cilia are uniform in length.
+
+Habitat similar to that of _L. infusionum_, in zoogloea masses.
+Length 26 to 30 mu; diameter 7 to 8 mu.
+
+Although Quennerstedt's description of _L. pusillus_ makes no mention
+of a caudal bristle, the size and other characters are so closely
+similar that I hesitate to make a new species. The bristle is
+extremely delicate, scarcely thicker than a cilium, and easily
+overlooked, yet with proper focussing of the condenser I found it on
+every specimen examined.
+
+
+[Illustration: Fig. 43.--_Lembus pusillus_.]
+
+
+KEY TO MARINE GENERA OF OPALINIDAE.
+
+Diagnostic characters: The form is oval, and the body may be short or
+drawn out to resemble a worm. They are characterized mainly by the
+absence of mouth and pharynx.
+
+Anterior end not pointed; body            Genus *_Anoplophrya_
+cylindrical; tapering
+
+Anterior end pointed; body elongate;      Genus _Opalinopsis_
+cylindrical; tapering
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus ANOPLOPHRYA Stein '60.
+
+(Stein '60; Claparede '60; Leidy '77; Vejdovsky '79; Kent '81;
+Balbiani '85; Buetschli '88; Shevyakov '96.)
+
+The general form is elongate, cylindrical or slightly flattened, with
+rounded ends, the posterior end tapering. The body is striated with
+clearly defined, often depressed lines, which run longitudinally and
+sometimes spirally. The contractile vacuoles are usually placed in
+rows upon the edges. The macronucleus is almost always long and
+band-formed, rarely oval, and generally extending through the entire
+length of the body. Micronuclei have been made out in one case.
+Reproduction is effected by simple cross division or by budding at
+the posterior end, and is frequently combined with chain formation.
+The main characteristic is the entire absence of mouth and
+oesophagus, the animals being parasitic in the digestive tract of
+various annelids. Parasites, salt-water forms.
+
+
+Anoplophrya branchiarum. Stein '52.  Fig. 44.
+
+_A. circulans_ Balbiani.
+
+The body is cylindrical to pyriform, in the latter case broadened
+anteriorly. Cuticle distinctly marked by longitudinal striations
+which take the form of depressions and give to the body a
+characteristic melon shape. The endoplasm contains a number of large
+refringent granules--probably body products. The nucleus is elongate,
+somewhat curved, and coarsely granular. A micronucleus lies in the
+concavity. The cilia are long, inserted rather widely apart along
+the longitudinal markings. The contractile vacuole is single and
+is located at the pointed end, which is directed backwards during
+locomotion. One specimen found free swimming among some algae.
+
+Length 104 mu; greatest diameter 36 mu.
+
+I was much surprised to find this form swimming about freely in the
+water; its mouthless condition showed it to belong to the family of
+parasites, the _Opalinidae_. As the name indicates, however, this
+species is an ectoparasite upon the gills, and Stein gave the name
+_branchiarum_ to a fresh-water form parasitic upon _Gammarus pulex_.
+The Woods Hole form is so strikingly similar to the figure of _G.
+branchiarum_ that, although the name was given to a fresh-water form,
+it obviously applies to this marine variety. One important difference
+is the presence of only one contractile vacuole in the marine form.
+
+
+[Illustration: Fig. 44.--_Anoplophrya branchiarum_.]
+
+
+KEY TO FAMILIES OF HETEROTRICHIDA.
+
+Cilia cover the body                      1
+
+Cilia reduced to certain                  2
+localized areas
+
+1. _Polytrichina_.
+
+   a. The mouth terminates a long         Family _Plagiotomidae_
+      peristomial furrow having an
+      adoral zone along the entire
+      left edge
+
+   b. Peristomial area a broad            Family _Bursaridae_
+      triangular area ending in mouth
+
+   c. Peristomial depression short;       Family _Stentoridae_
+      limited to the anterior end; its
+      plane at right angles to the
+      long axis of body; surface of
+      peristome striated and ciliated;
+      no undulating membranes
+
+2. _Oligotrichina_.
+
+   a. Peristome without cilia; cilia      Family _Halteriidae_
+      limited to one or more girdles
+      about body
+
+      One marine genus                    *_Strombidium_
+
+   b. Thecate forms; the body is          Family _Tintinnidae_
+      attached by a stalk to the cup;
+      within the adoral zone is a ring
+      of cilia.
+
+   c. The peristomial depression is       Family _Ophryoscolecidae_
+      deep and funnel-like; cuticle
+      thick, with posterior spine-like
+      processes.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+KEY TO THE MARINE GENERA OF PLAGIOTOMIDAE.
+
+Diagnostic characters: The peristome is a narrow furrow which begins,
+as a rule, close to the anterior end and runs backward along the
+ventral side, to the mouth, which is usually placed between the
+middle of the body and the posterior end. A well-developed adoral
+zone stretches along the left side of the peristome, and is usually
+straight.
+
+1. Body cylindrical; size medium;         Genus _Metopus_
+   peristome long and turns sharply
+   to the left at the extremity
+
+2. No torsion in the peristome;           Genus _Blepharisma_
+   undulating membrane is confined
+   to the posterior part of peristome
+
+3. No peristomial torsion;                Genus _Spirostomum_
+   body highly contractile;
+   no undulating membrane
+
+
+KEY TO THE MARINE GENERA OF BURSARIDAE.
+
+Diagnostic characters: The body is usually short and pocket-like, but
+may be elongate. The chief characteristic is the peristome, which is
+not a furrow, but a broad triangular area deeply insunk and ending in
+a point at the mouth. The adoral zone is usually confined to the left
+peristome edge, or it may cross over to the right anterior edge.
+
+1. The anterior half of the body          Genus _Balantidium_
+   tapers to nearly a point in front;
+   the peristome is narrowest at the
+   apex; the mouth is the entire
+   peristome base.
+
+2. The anterior end does not taper;       Genus *_Condylostoma_
+   the peristome is widest at the end
+   of the body; the mouth is clearly
+   defined.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus CONDYLOSTOMA (KONDYLOSTOMA Bory de St. Vincent 1824) Dujardin
+'41
+
+(Dujardin '41; Claparede & Lachmann '58; Stein '59, '67; Cohn '66;
+Quennerstedt '67; Wrzesniowski '70; Buetschli '76, '88; Kent '81;
+Maupas '83; Shevyakov '96.)
+
+Colorless and more or less flexible animals of medium size. The
+general form is elongate and cylindrical or somewhat smaller
+anteriorly. The posterior end is broadly rounded, the anterior end
+somewhat truncate and oblique. The peristome is broad and triangular,
+the base of the triangle being the entire anterior end of the body.
+The entire length of the peristome is one-fourth or less of the body
+length. The mouth is large and placed at the apex of the peristomial
+triangle and opens into a comparatively small oesophagus. The right
+edge of the peristome is lamellate and bears a clearly defined
+undulating membrane. The adoral zone is well developed upon the left
+edge of the peristome, from which it passes around anteriorly to the
+right edge. The surface of the peristome is free from cilia, but
+the rest of the body is uniformly coated with small active cilia.
+Contractile vacuoles are not safely determined. Buetschli thinks
+there is probably one terminal vacuole, but some observers deny this
+(_e.g._ Maupas). Others describe them on the dorsal side of the
+posterior end (Quennerstedt). The macronucleus is long and beaded and
+placed upon the right side. Micronuclei are numerous and scattered
+along the macronucleus. The anus is terminal and dorsal. Food
+consists of large and small particles. Movement rapid, free swimming,
+alternating with resting periods; in some cases an undulating or
+wriggling movement is seen, showing clearly the flexibility of the
+body. Fresh and salt water.
+
+
+Condylostoma patens Mueller.  Fig. 45.
+
+The body is elongate, somewhat sac-like, five or six times as long
+as broad, plastic, and frequently contains brightly colored food
+granules. The triangular peristome takes up the greater part of the
+anterior end, and the mouth is situated at the sharper angle of the
+triangle, about one-fourth of the total length from the anterior end.
+The cuticle is longitudinally striated, the lines having a slightly
+spiral course. They are not closely set, and fine cilia are thickly
+inserted along their edges. The endoplasm is granular and viscous.
+The motile organs consist of an adoral zone of membranelles, which
+stretch along the left edge of the peristome and the front edge of
+the body. The right edge of the peristome supports an undulating
+membrane. The nucleus is moniliform and extends the full length of
+the left side; a number of micronuclei are distributed along its
+course (Maupas).
+
+Length 400 mu; diameter at widest part 105 mu. Maupas gives the length
+from 305 mu to 495 mu; and Stein 376 mu to 564 mu. Very common.
+
+For a more extended account of the structures, see the excellent
+description by Maupas '83.
+
+
+[Illustration: Fig. 45.--_Condylostoma patens_.]
+
+
+KEY TO THE MARINE GENERA OF STENTORIDAE.
+
+Diagnostic characters: The peristome is relatively short and limited
+to the front end of the animal, so that its plane is nearly at right
+angles to that of the longitudinal axis of the body. The adoral zone
+of cilia either passes entirely around the peristome edge or ends at
+the right-hand edge. The surface of the peristome is spirally
+striated and provided with cilia. Undulating membranes are absent.
+
+1. Peristome circular in outline;         Genus _Stentor_
+   limited to the anterior end
+
+2. The peristome is drawn out into two    Genus _Folliculina_
+   wing-like processes; tube-dwelling
+
+
+Genus STROMBIDIUM Cl. & Lach. '58.
+
+(Stein '67; Buetschli '73; Fromentel '74; Kent '81; Gruber '84; Entz
+'84; Maupas '83. Buetschli '88.)
+
+Small, colorless (except for ingested food) animals with
+characteristic springing movements. The form is usually constant, but
+in some cases may be plastic like _Astasia_; it is usually globular
+or conical, the posterior end being more or less pointed, the
+anterior end broadest. The latter is surrounded by a complete circle
+of the adoral zone, the oral end of which passes into a peristomial
+depression which extends deep into the middle of the body. The mouth,
+with a very small oesophagus, lies at the bottom of the inturned
+peristome. The region surrounded by the adoral zone is frequently
+drawn out into an anterior process, occasionally bearing a pigment
+mass. The ventral surface in some cases bears cilia, which may be
+distributed or restricted to a row of large cilia. Trichocysts are
+usually present and may be widely spread, limited to the posterior
+region, or arranged in a girdle about the middle. The contractile
+vacuole is simple, and posterior in position. The macronucleus
+is spherical and usually central in position. Movement is rapid
+swimming, combined with resting and floating periods, the latter
+usually terminated by a sudden leap.
+
+Fresh and salt water; more common in the latter.
+
+
+Strombidium caudatum Fromentel '74.  Fig. 46, a, b, c.
+
+Fromentel described a fresh-water form of this genus with a caudal
+appendage. The body is pyriform, broadly truncate on the anterior
+end, in the middle of which rises a papilliform process (Schnabel).
+On this process is a heap of pigment granules, which, however, are
+not constant. A ring of long cirri surround the anterior end and pass
+into the peristome, and from the left edge of this line of cirri a
+large adoral zone continues down to the mouth. The peristome is
+elongate and sac-form, and the mouth lies at the posterior extremity.
+With the exception of a caudal filament there are no other motile
+organs; this is about half as long as the body, structureless,
+hyaline, and sharply pointed. It splits up into a bundle of fine
+fibers upon treatment with caustic potash (c). The cirri emerge from
+minute hollows in the edge of the anterior border. The cortical
+plasm contains peculiar rod-like bodies, which look more like lines
+or markings than like rods or trichocysts. The nucleus is large,
+spherical, and placed in the center of the body. The contractile
+vacuole is posterior.
+
+Length without appendage is about 35 mu; greatest diameter 15 to 18 mu.
+In decaying vegetable matter. Common.
+
+
+[Illustration: Fig. 46.--_Strombidium caudatum_.]
+
+
+Although Fromentel's species is incompletely described, it is very
+evident that the organism corresponds fairly well with the Woods Hole
+variety. His was a fresh-water type; this is marine, but the caudal
+filament and the contractile vacuole are similar. Certainly in this
+case the organism can not be regarded as a Vorticella broken off its
+stalk, as Kent '81 suspected. The anterior process with its pigment
+spot; the cirri, the spherical nucleus, the position of the vacuole,
+etc., are all opposed to such an interpretation which Kent applied to
+the original species. Neither can it be a Tintinnoid. I place it
+provisionally as _S. caudatum_.
+
+
+KEY TO THE MARINE GENERA OF TINTINNIDAE.
+
+Diagnostic characters: Body attached by a stalk to a cup. Inside the
+zone of membranelles is a ring of cilia (par-oral).
+
+1. The test is gelatinous and more or     Genus _Tintinnidium_
+   less covered by foreign particles
+
+2. The test is chitinous and clear.       Genus _Tintinnus_
+   No foreign particles.
+
+3. The test is chitinous; covered by      Genus *_Tintinnopsis_
+   foreign particles, growth rings
+   frequent
+
+4. The test is chitinous, often           Genus _Codonella_
+   covered by foreign particles.
+   The test is marked by discoid,
+   circular, or hexagonal spots.
+
+5. The test is perforated by pores        Genus _Dictyocysta_
+   of circular or hexagonal form.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus TINTINNOPSIS Stein '67.
+
+(Stein '67; Kent '81; Daday '87; Buetschli '88.)
+
+Medium-sized ciliates, inclosed in a chitinous lorica with embedded
+sand crystals. The form of the house, or lorica, varies greatly.
+In some cases the mouth opening is wide, giving the lorica a bell
+form; it may be long and tubular, short and spherical, or variously
+indented. The animal is attached, as in the closely allied genus
+_Tintinnus_, by a peduncle to the bottom of the lorica. The anterior
+end of the animal is inclosed by two complete circles of cilia;
+one, the outer, forming the adoral zone, is composed of thick
+tentacle-like membranelles, the other consists of shorter cilia
+within the adoral zone. The mouth leads into a curved oesophagus
+containing rows of downward-directed cilia (Daday). The entire body
+is covered with cilia, but as the lorica is always opaque these can
+be made out only when the animal is induced to leave the house. The
+only difference between this genus and _Tintinnus_ is the covering
+of foreign bodies--usually sand crystals. Movement is rapid and
+restless, and peculiarly vibratory, owing to the apparent awkwardness
+in moving the house.  Salt water.
+
+
+Tintinnopsis beroidea Stein, var. plagiostoma Daday.  Fig. 47.
+
+Synonym: _Codonella beroidea_ Entz '84.
+
+The shell is colorless, thimble-shaped, with a broadly rounded
+posterior end. The body is cylindrical. The internal organs were not
+observed. Membranelles 24 in number. Length 50 mu; greatest diameter
+40 mu.
+
+
+[Illustration: Fig. 47.--_Tintinnopsis beroidea_.]
+
+
+Var. compressa Daday '87.
+
+The posterior end of the shell is pointed, the lower third of the
+shell is swollen, the upper third is uniform in diameter and without
+oral inflation or depression. Nucleus not seen.
+
+Length 70 mu; greatest diameter 48 mu.
+
+
+Tintinnopsis davidoffi Daday.  Fig. 48.
+
+The shell is large, elongated, and provided with a considerable
+spine. The chitin of the shell is covered with silicious particles of
+diverse size. The internal structures were not observed.
+
+Length of shell and spine 230 mu; diameter of the oral aperture 54 mu.
+
+
+[Illustration: Fig. 48.--_Tintinnopsis davidoffi_.]
+
+
+The variations of these species are considerable, and as the internal
+structures, such as the nucleus, are essential in fixing their
+systematic position, I place them as above, provisionally, and until
+further observations can be made.
+
+
+KEY TO FAMILIES OF HYPOTRICHIDA.
+
+a. Peristome indistinct; cilia on         Family _Peritromidae_
+   ventral surface uniform and not        One genus, *_Peritromus_
+   differentiated into cirri
+
+b. Peristome more or less indistinct;     Family _Oxytrichidae_
+   cilia reduced to a few rows on the
+   ventral surface; anal and frontal
+   cirri present
+
+c. Cilia entirely reduced; frontal        Family _Euplotidae_
+   and anal cirri present or reduced;
+   macronucleus band-formed or spherical
+
+d. Peristome reduced to left edge and     Family _Aspidiscidae_
+   does not reach over the anterior       One genus, *_Aspidisca_
+   margin
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PERITROMUS Stein '62.
+
+(Stein '62, '67; Maupas '83.)
+
+The body is flat, colorless or tinged with yellow, and contractile.
+It is elliptical in outline, with broadly rounded ends; in some
+cases the left edge is slightly incurved, the right edge convex.
+The ventral surface is flat, the dorsal surface is arched in the
+middle region of the body. The edges being flat are somewhat more
+transparent than the remainder of the body. The ventral surface is
+striated by longitudinal straight or slightly curved lines, the
+dorsal surface is smooth and without cilia. (Maupas describes
+bristles on the back, but this is not corroborated.) The adoral zone
+is fairly well developed, but not distinctly marked off from the
+remaining ventral surface. It begins on the right side and extends
+entirely around the frontal margin and down the left side below the
+middle of the body, where it turns suddenly to the right, entering
+the slightly insunk peristome. The mouth leads into a short,
+indistinct oesophagus. One contractile vacuole is situated in the
+dorsal swelling at the posterior end of the animal. Macronucleus
+double, one in each side of the dorsal swelling. Movement is slow
+and creeping, with a peculiar method of contracting the more hyaline
+edge, which may turn upward or around a foreign object.
+
+Fresh (?) and salt water.
+
+
+Peritromus emmae Stein.  Fig. 49.
+
+With the characters of the genus.
+
+
+[Illustration: Fig. 49.--_Peritromus emmae_, ventral and lateral
+aspects.]
+
+
+KEY TO THE MARINE GENERA OF OXYTRICHIDAE.
+
+Diagnostic characters: The peristome is not always marked off from
+the frontal area. In the most primitive forms the cilia on the
+ventral surface are similar to those of the preceding family
+(_Peritromidae_). Usually some of the anterior and some of the
+posterior cilia are fused into cirri, distinguished as the frontal
+and anal cirri, respectively. In the majority of forms all of the
+cilia are thus differentiated; strong marginal cirri are formed in
+perfect rows, and ventral cirri in imperfect rows. In addition to the
+adoral zone there is an undulating membrane on the right side of the
+peristome, and in some cases a row of cilia between the membrane
+and the adoral zone. These are the par-oral cilia and they form the
+par-oral zone.
+
+1. The posterior end is pointed or        2
+   tail-like
+
+   The posterior end is rounded;          5
+   not tail-like
+
+2. The front end is pointed               3
+
+   The front end is rounded               4
+
+3. Frontal and anal cirri absent;         Genus _Stichotricha_
+   often tube-forming
+
+   Eight frontal and 3 caudal cirri;      Genus _Gonostomum_
+   not tubiculous
+
+4. Anal cirri present; with or            Genus *_Epiclintes_
+   without short lateral bristles
+
+   Anal cirri absent; no bristles         Genus _Uroleptus_
+
+5. With frontal cirri                     6
+
+   No frontal cirri; 2 to 3 rows of       Genus _Holosticha_
+   ventral cirri; anal cirri small
+
+6. Right margin of peristome straight     Genus _Oxytricha_
+   as far as the anterior end; 5 rows
+   ventral cirri; 5 anal cirri
+
+   Right margin of peristome curved       7
+
+7. Five rows or less of ventral cirri     8
+
+   More than 5 rows of ventral cirri      Genus _Urostyla_
+
+8. Membranelles normal; 5-10 anal         Genus *_Amphisia_
+   cirri; no caudal cirri
+
+   Membranelles normal; 5 to 10 anal      Genus _Stylonychia_
+   cirri; 3 caudal cirri
+
+   Membranelles very large and            Genus _Actinotricha_
+   powerful; adoral zone not
+   continued to mouth; 5 anal cirri
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EPICLINTES Stein '62.
+
+(Stein '62, '64, '67; Mereschowsky '79; Gruber '87; Buetschli '88.)
+
+Very active, contractile, colorless forms of rather small size. In
+the fully expanded condition the body is oval and long, with its
+greatest width in the center or at the front half of the body. The
+posterior end is always drawn out into a relatively long tail, which
+is extremely elastic. The peristome is short and stretches around the
+front end of the animal. In the frontal region are from one to three
+rows of cirri. The ventral surface is covered with longitudinal rows
+of cilia, the number of rows being in dispute (6 to 7 according to
+Stein; 9 according to Mereschowsky and Rees) Some of these cilia
+project from the lateral edges and from the posterior end, where
+they are slightly elongated. The anus is dorsal and placed at the
+beginning of the posterior process. Macronucleus probably double.
+Movement is rapid and restless, the tail process contracting to jerk
+the body backward. Salt water.
+
+
+Epiclintes radiosa Quenn.  Fig. 50.
+
+Synonym: _Metra radiosa_ Quenn.
+
+The body is elongate, slightly narrowed anteriorly, and drawn out
+posteriorly into a long, retractile, tail-like portion. Five large
+cirri extend outward from the anterior extremity. The caudal portion
+may be extended to a distance equal to twice the length of the body
+or contracted to half the length. The peculiar nervousness of this
+form made it extremely difficult to study, and the oral region was
+imperfectly made out. The anterior cirri appear to line the upper
+left border of the peristome, which is marked by a row of large
+cilia. The peristome begins upon the right side of the anterior end
+and passes backward and to the left, narrowing at this point. The
+mouth is very small and difficult to see. It is apt to stay in
+one locality under zoogloea, switching back and forth with great
+vivacity, or hanging on by the posterior cilia while the anterior
+end stretches out in the surrounding medium. Nucleus and contractile
+vacuole were not observed. Length 45 mu.
+
+
+[Illustration: Fig. 50.--_Epiclintes radiosa_.]
+
+
+Genus AMPHISIA Sterki '78.
+
+(Sterki '78; Kent '81; Buetschli '88.)
+
+The body is plastic and soft, colorless or slightly tinged with
+yellow or red. In form it is oval or elongate, the posterior end
+is rounded and slightly reduced in diameter, but does not form a
+distinct tail. The anterior end is also rounded and similarly reduced
+in width. There are two rows of marginal cirri (_Randcirren_), which
+may be placed some distance from the edge, and two or three rows of
+ventral cirri between them. There are from 3 to 5 frontal cirri of
+larger size than those of the ventral rows, and from 5 to 10 anal
+cirri. (The genus _Holosticha_ is similar in all respects save
+the presence of frontal cirri.) The macronucleus is double; the
+contractile vacuole is central and on the left side. The peristome
+is long and rather narrow and carries an undulating membrane on its
+right margin. Fresh and salt water.
+
+
+Amphisia kessleri Wrzes. '77.  Fig. 51.
+
+Synonyms: _Trichoda gibba_ Mueller; _Oxytricha gibba_ Stein '59; _O.
+velox?_ Quen. '69; _O. kessleri_ Wrzes. '77.
+
+Body elongate, slightly sigmoid and swollen in the center, about
+3-1/2 times as long as broad; the rounded anterior end is turned to
+the left, the similarly rounded posterior end to the right; both ends
+taper slightly. The peristome is long and narrow, with a distinct
+adoral zone which appears broken in its course. To the right of this
+adoral zone is a single line of preoral cilia. On the right border of
+the peristome is an undulating membrane. The three frontal cirri form
+a triangle and the five smaller anal cirri form a continuous line
+with the broken row of ventral cirri. There are two and one-half rows
+of ventral cirri and the marginal cirri are drawn in until they are
+ventral in position.
+
+Length 135 mu; greatest width 40 mu.
+
+
+[Illustration: Fig. 51.--_Amphisia kessleri_.]
+
+
+This variety differs from _O. kessleri_ as described by Wrzesniowski
+in having three frontal cirri instead of four. Another difference
+is in the structure of the nuclei and in their position. These
+differences are too minute to warrant a specific name. _O. velox_ of
+Quennerstedt is probably the same as _0. kessleri_, but differs in
+having three complete rows of ventral cirri. _O. velox_ has three
+frontal cirri in a line, thus differing from the Woods Hole form.
+
+
+KEY TO THE MARINE GENERA OF EUPLOTIDAE.
+
+Diagnostic characters: Cilia, as well as the frontal, marginal, and
+ventral cirri, very much reduced; the anal cirri, on the other hand,
+are always present. The macronucleus is band-form.
+
+1. Frontal cirri more than 8              2
+
+   Frontal cirri less than 8              3
+
+2. Eleven marginal cirri on the left      Genus _Certesia_
+   side; 11 frontal cirri
+
+   Four marginal cirri, 2 on each         Genus *_Euplotes_
+   side; 9 to 10 frontal cirri
+
+3. Seven frontal, 5 anal, 3 right         Genus *_Diophrys_
+   marginal, and 2 left marginal
+   cirri
+
+   No frontal, 5 anal, 3 right,           Genus *_Uronychia_
+   and 2 left marginal cirri
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus EUPLOTES (Ehr. 1831) Stein '59.
+
+(Ehrenberg '31, '38; Stein '59; Cl. & Lach. '58; Quennerstedt '65,
+'67, '69;  Buetschli '88; Kent '81; Gourret & Roeser '88; Moebius '88.)
+
+Small to medium-sized forms. Rigid in form, colorless, or green by
+chlorophyl. They are quite flat on the ventral surface but decidedly
+arched dorsally, and the contour is usually oval. The anterior end is
+broadly rounded to truncate; the posterior end is similarly rounded,
+or may be somewhat pointed. The mouth is placed centrally or near
+the left margin, and from it the right edge of the peristome forms a
+curved line to the left, which bends forward, thus making the greater
+part of the left edge the peristomial area. In front the peristome
+bends sharply to the right and extends as far as the right end of the
+adoral zone. Upon the frontal and median ventral surface are 9 to 10
+great cirri (_Bauchwimpern_ of Stein). Posteriorly five great anal
+cirri stretch out beyond the posterior body margin. In addition to
+these there are two smaller marginal cirri upon the left body edge,
+and two similar ones on the hinder part of the body. The dorsal
+surface is rarely smooth, but usually is marked by longitudinal
+ridges, and rows of dorsal bristles have been described. The single
+contractile vacuole lies on the right side in the region of the
+anal cirri, sometimes just above them, sometimes below. The anus is
+posterior and on the right side. The characteristic macronucleus is
+long and band-form, its main portion being usually on the left side
+with an anterior and a posterior arm toward the right. Movement is
+rapid swimming, which, however, is frequently broken by creeping
+periods, during which the animals appear to be examining the foreign
+body on which they creep.
+
+Fresh and salt water.
+
+
+Euplotes charon Ehr.  Fig. 52.
+
+Synonyms: _Trichoda charon_ Mueller; _Ploesconia charon_; _P.
+affinis_, _subrotunda_, _radiosa_, _longiremis_, Dujardin '41.
+
+The body is oval, small, and somewhat variable in length. The
+carapace is strongly marked upon the dorsal side by deep longitudinal
+grooves, 6 to 8 in number; the grooves may be absent, however. The
+adoral zone extends to the posterior third of the body, the mouth
+and oesophagus are directed anteriorly. There are 10 ventral cirri,
+7 of which are on or near the frontal border and 3 near the right
+edge. There are 5 posterior cirri and 4 anal cirri, of much smaller
+size. The cirri may or may not be fimbriated, the latter condition
+indicating the approaching disintegration of the body and is
+abnormal. The macronucleus is long and band-formed or horseshoe
+shape. The contractile vacuole lies on the right side dorsal to the
+posterior cirri.
+
+Fresh and salt water. Length 45 mu; diameter 25 mu.
+
+
+[Illustration: Fig. 52.--_Euplotes charon_, dorsal and ventral
+aspects.]
+
+
+Euplotes harpa Stein.  Fig. 53.
+
+The body is elongate, oval, somewhat widened anteriorly, and has
+rounded ends. The frontal margin is three-toothed. Ten ventral cirri.
+Dorsal surface provided with 8 longitudinal markings. The peristome
+is long and broad, with considerable variation. The adoral zone
+consists of powerful membranelles arranged in a continuous curve
+from the mouth to the extreme right frontal margin. Seven of the 10
+ventral cirri are situated at the anterior extremity; the remainder
+are arranged in a triangle on the right edge. The anal cirri, 5 in
+number, are long and stiff; the marginal cirri smaller and finer. The
+nucleus and contractile vacuole are similar to those of the preceding
+species.
+
+Length 95 mu; width 54 mu.
+
+
+[Illustration: Fig. 53.--_Euplotes harpa_.]
+
+
+Genus DIOPHRYS Dujardin '41.
+
+(Buetschli '88.)
+
+Medium size, colorless to yellow, rigid in form. The body contour
+is oval, the anterior end being rounded or slightly reduced, the
+posterior end usually cut in on the right side. The peristome is
+broad but less extensive than in _Euplotes_, and may extend beyond
+the middle of the body. Its right edge is convex toward the right
+side, extends forward and does not turn again to the right. The
+anterior ventral surface has 7 to 8 scattered cirri and just behind
+the mouth is a transverse row of large anal cirri. In the sharp
+in-cut of the posterior end are three great angular cirri. Two
+lateral cirri are placed on the left of the median line between
+the mouth and the anal cirri, and usually in a slight hollow. The
+contractile vacuole is on the right side in the vicinity of the
+anal cirri. The macronucleus is in two parts, each band-form, one
+anterior, the other posterior in position. Movement is rapid and
+steady. Salt water.
+
+
+Diophrys (Styloplotes) appendiculatus Stein '59.  Fig. 54.
+
+Synonyms: _Styloplotes appendiculatus_ Stein '59; Kent '81;
+Quennerstedt '67, etc.
+
+The general form resembles _Euplotes_. Its outline is oval and
+regular except at the posterior end on the right side, where there is
+a considerable indentation. The frontal margin is characterized by a
+row of powerful membranelles, which become smaller at the peristome
+and at the mouth they are of characteristically small size. The
+ventral cirri are 7 in number. Five of them are in one row from the
+anterior end down the right side nearly to the anal cirri; 1 is on
+the frontal border between the first two; 1 lies just anterior to the
+second anal cirrus from the right side. The 5 anal cirri are large
+and powerful and extend some distance beyond the posterior end of the
+body. In all specimens observed these cirri curve to the left. Dorsal
+to the anal cirri and placed deep into the dorsal pit are 3 large,
+sharply curved cirri, which in most cases are fimbriated, but when
+the specimens are normal these are pointed and curve abruptly to the
+right. Two smaller cirri lie to the left of the group of anal cirri.
+The peristome is well-marked by the adoral zone, and upon its right
+border there is a row of cilia, and a similar row of cilia runs along
+the base of the oral membranelle. The macronucleus is double and
+consists of two elongate cylindrical masses lying parallel with
+one another. One of these is in the anterior region; the other is
+posterior. The contractile vacuole lies dorsal to the anal cirri
+and anterior to the three dorsal cirri. The movement and general
+activities resemble those of _Euplotes_.
+
+Length 50 mu; diameter 25 mu.
+
+
+[Illustration: Fig. 54.--_Diophrys appendiculatus_.]
+
+
+Genus URONYCHIA Stein '52.
+
+(Stein '59, '67; Quennerstedt '67; Kent '81; Buetschli '88.)
+
+Medium-sized colorless ciliates of usually constant body form. The
+body is somewhat short and oval in outline. The anterior end is
+broadly truncate, the posterior end rounded or slightly pointed. The
+ventral and dorsal surfaces are considerably arched and the latter
+usually has a number of rows of longitudinal stripes. The open
+peristome is broad and reaches back to the middle of the ventral
+surface and beyond. According to Stein, the two edges can approach
+each other, thus opening and closing the peristomial area. Its right
+edge forms a greater angle with the front edge than in the genus
+_Euplotes_, and the left edge forms a greater angle with the front
+edge than in that genus. The left edge also appears to cover over the
+adoral zone slightly. There are no ventral cirri in front, but on the
+posterior ventral surface are 7 great springing cirri. Five of these
+are inserted on the right aide in a deep in-sinking, and the other 2
+in a similar depression on the left ventral surface. Above the 5
+right-side cirri, _i.e._, dorsal to them, but in the same depression,
+are 3 angular cirri. A few edge cirri are found to the left of them
+and another to the right of the 5 cirri. The contractile vacuole is
+on the left side between the main groups of cirri. The macronucleus
+is band-form or spherical, and is situated in the middle region of
+the body. Movement consists in forward swimming with sudden springs.
+
+Salt water.
+
+
+Uronychia setigera, n. sp.  Fig. 55.
+
+This species is very common in the Woods Hole waters. It is small,
+colorless, and very active. The most characteristic feature is
+the posterior end with its relatively enormous cirri, which are
+apparently large enough for an animal four times its size. The form
+is ovoid, widened posteriorly.
+
+The ventral surface is flat and has two excavations in the posterior
+end. The right hollow is larger and contains 5 great cirri of unequal
+size, the extreme right one being the largest. The left hollow
+contains 2 cirri, also of dissimilar size. Dorsal to the 5 right
+cirri are 3 sickle-formed cirri, which are usually fimbriated. These
+are pointed and curve regularly to the left. The peristome is wide
+and open, and a small pocket-like hollow on its left border indicates
+the region of the mouth. The adoral zone runs into this pocket
+and the mouth is located in its lower right-hand corner. In _U.
+transfuga_ the right border is generally described as having a
+membrane of extreme delicacy. I was unable to see such a membrane in
+this form, but in its place there are 2 flagella-like cirri extending
+from the margin of the mouth-opening into the peristome, and these
+vibrate slowly. I do not believe these could be the moving edge of an
+undulating membrane, for they are quite distinct. The macronucleus is
+spherical instead of band-form, and a single micronucleus is closely
+attached. This is unlike the European species _U. transfuga_, in
+which the nucleus is elongate. The contractile vacuole lies between
+the two sets of posterior cirri. There are no marginal folds like
+those of the European species.
+
+Length 40 mu; width 25 mu. Common.
+
+
+[Illustration: Fig. 55.--_Uronychia setigera_.]
+
+
+Genus ASPIDISCA Ehr. 1830.
+
+(Perty '52; Cl & Lach. '58; Stein '59; Quennerstedt '65, '67, '69;
+Mereschowsky '79; Kent '81; Buetschli '88.)
+
+Small, colorless, and rigid forms, with nearly circular to oval
+contour. The left side is usually straight, or at least but slightly
+convex. The right side is much more convex, and the right margin is
+considerably thickened. The ventral side is flat, the dorsal surface
+convex, with from one to several longitudinal ridges which run more
+or less parallel with the right edge. The peristome is limited to the
+left edge, where it forms a small depression which may or may not
+reach the anterior border, but which in no case runs around the
+anterior margin. The left peristome margin in some cases grows
+over the peristome depression toward the right, thus making a sort
+of cover for the peristome. In the posterior region is a deep
+depression, from which 5 to 12 cirri take their origin. Seven or 8
+cirri are placed in the anterior half of the ventral surface and
+are arranged more or less in rows. The anus is on the right side in
+the region of the anal cirri (Stein). The contractile vacuole is
+generally on the right side and similarly located. The macronucleus
+is a horseshoe-shaped body. Movement rapid, somewhat in circles, and
+rather uniform.
+
+Fresh and salt water.
+
+
+Aspidisca hexeris Quennerstedt '67.  Fig. 56.
+
+The carapace is elliptical, about 1-1/2 times as long as broad,
+rounded at the extremities. The left border of the carapace bears a
+spur-like projection. The ventral cirri are short and thick, and are
+very characteristic of the species. When moving slowly they look much
+like nicely-pointed paint brushes, but when the animal is compressed
+they quickly become fibrillated, and then look like extremely old and
+worn brushes. These cirri are placed in depressions in the ventral
+surface and each one appears to come from a specific shoulder. At the
+posterior end an oblique hollow bears 6 unequal cirri placed side
+by side. The extreme right cirrus is the largest, and they become
+progressively smaller to the opposite end. Dorsal to these lies the
+contractile vacuole. The peristome is in the posterior half of the
+body and an undulating membrane extends from it into the oesophagus.
+The dorsal surface is longitudinally striated by 5 or 6 lines, which
+are usually curved. The nucleus is horseshoe-shaped and lies in the
+posterior half of the body. Length 68 mu; diameter 48 mu.
+
+
+[Illustration: Fig. 56.--_Aspidisca hexeris_.]
+
+
+This form was incorrectly mentioned as _Mesodinium_ sp. by Peck '95:
+
+In the figure given by Quennerstedt there are only 7 ventral cirri.
+In the Woods Hole form there are 8, 7 of which are anterior, 6 of
+them about one central one. The eighth cirrus is by itself, near the
+base of the largest posterior cirrus. These cirri, in spite of their
+size, are easily overlooked and more easily confused, but by using
+methylene blue they can be seen and counted.
+
+
+Aspidisca polystyla Stein.  Fig. 57.
+
+This species is similar to _A. hexeris_, but is smaller, very
+transparent, and without the spur-like process on the left edge of
+the carapace. The chief difference, however, lies in the number of
+anal cirri. These are 10 in number and they are arranged obliquely as
+in the preceding species, with the largest one on the right and the
+smallest on the left. The ventral cirri are 8 in number, and are
+arranged in two rows, one of which, the right, has 4 cirri closely
+arranged, the other having 3 cirri close together and one at some
+distance, near the largest anal cirrus. The peristome, contractile
+vacuole, and nucleus are similar to the preceding. Length 36 mu; width
+22 mu.
+
+
+[Illustration: Fig. 57.--_Aspidisca polystyla_.]
+
+
+Stein assigns only 7 ventral cirri to this species, but he also
+describes 2 very fine bristle like cilia (p. 125) and pictures them
+in figs. 18, 19, 20, and 21 of his Taf. III in the same relative
+position as my eighth cirrus. I am positive that cilia do not occur
+on the ventral face of this form, and that the characteristic cirri
+are the sole locomotor organs.
+
+
+KEY TO FAMILIES OF PERITRICHIDA.
+
+a. Peristome drawn out into               Family _Spirochonidae_
+   funnel-like process; parasitic
+
+b. Adoral zone and circlet of cilia       Family _Lichnophoridae_
+   at opposite end. Adoral zone           (one genus, *_Lichnophora_)
+   left-wound. Parasitic.
+
+c. Adoral zone a left-wound spiral.       Family _Vorticellidae_
+   Attached or unattached forms.
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus LICHNOPHORA Claparede '67.
+
+(Gruber '84; Fabre-Domergue '88; Buetschli '88; Wallengren '94;
+Stevens 1901.)
+
+Small or medium-sized colorless animals, extremely elastic and
+flexible. The anterior part, bearing the adoral zone, is round or
+oval in ventral view, and has a flat ventral and a highly arched
+dorsal surface. The posterior end of the animal is reduced to a
+stalk-like structure which is broadened at the extremity to form
+a sucking disk. The surface of this disk and the surface of the
+peristome may be brought into the same plane by the characteristic
+bending of the stalk portion. A ciliated girdle is placed at the
+edge of the sucking disk. A well-developed adoral zone incloses the
+peristome; it begins at the mouth on the left side and includes
+nearly all of the peristome in its left-wound spiral, the extremity
+approaching closely the end near the mouth. The macronucleus is a
+long-beaded structure, or it may be in several parts connected by
+strands (Gruber). The contractile vacuole is on the left side in the
+region of the mouth. Salt water.
+
+
+Lichnophora macfarlandi Stevens.  Fig. 58.
+
+The body is elongate; oral disk variable in form, attachment disk
+clearly defined and constant. The stalk is very contractile and
+elastic, constantly changing in shape. When detached from the host
+the animal moves with a very irregular and indefinite motion. When
+attached it moves freely over the surface on its pedal disk. The
+latter is bordered by four membranes composed of cilia. A distinct
+axial fiber extends from the pedal disc to the peristome and gives
+off a number of branches. This fiber is analogous to the myonemes
+in _Vorticella_. An indistinct longitudinal furrow can be made out
+occasionally. The nucleus is in 5 or 6 separate pieces, of which 1
+is found in the pedal disk and 1 or 2 in the neck.
+
+On the egg capsules of _Crepidula plana_; also reported upon annelids
+at Woods Hole.
+
+Length 60 mu from disk to extremity of the peristomial disk.
+
+
+[Illustration: Fig. 58.--_Lichnophora macfarlandi_.]
+
+
+This form does not agree in all respects with Stevens's species, but
+the agreement is so close in other respects that I believe it can be
+safely identified as _L. macfarlandi_. The mode of life is different,
+and the macronucleus is different, there being from 25 to 30
+fragments in Stevens's form and only 5 or 6 in the present one. There
+is, however, the same evidence of chain formation in both of them.
+The length of the oral cilia in  Stevens's form is 18 mu in fixed and
+30 mu in living forms. In the Woods Hole form the cilia are not more
+than half that length.
+
+
+KEY TO THE MARINE GENERA OF VORTICELLIDAE.
+
+Diagnostic characters: Attached or unattached forma of peritrichous
+ciliates in which the adoral zone seen from above forms a right-wound
+spiral. A secondary circlet of cilia around the posterior end may be
+present either permanently or periodically.
+
+1. Posterior ciliated girdle              3
+   permanent around an attaching disk
+
+2. Posterior ciliated girdle,             4
+   temporary during motile stage
+
+3. Body cylindrical:
+
+  (a) With ring of stiff bristles         Genus _Cyclochaeta_
+      above the ciliated girdle
+
+  (b) Without accessory ring of           Genus _Trichodina_
+      bristles; with velum
+
+         Body conical; general            Genus _Trichodinopsis_
+         surface ciliated
+
+4. No test and no stalk                   Genus _Scyphidia_
+
+5. No test; with stalk containing         8
+   contractile thread
+
+6. No test; with stalk but without        Genus _Epistylis_
+   contractile thread
+
+7. With a test; with or without           Genus *_Cothurnia_
+   a stalk
+
+8. Individuals solitary                   Genus *_Vorticella_
+
+   Individuals colonial;                  Genus *_Zoothamnium_
+   entire colony contractile
+
+   Individuals colonial; parts            Genus _Carchesium_
+   only of the colony contractile
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus VORTICELLA (Linnaeus 1767) Ehr. '38
+
+(Bell Animalcule Leeuwenhoek 1675; Ehrenberg '38; Dujardin '41; Stein
+'51; Cl. & Lach. '58; Greeff '70; Buetschli '88; Kent '81; Stokes '88;
+etc.)
+
+Medium-sized ciliates of general bell-like form. They may be
+colorless, or yellow and green through the presence of Zoochlorella.
+When not contracted, the peristome end is widespread, rarely
+narrowed. The adoral zone and peristome agree with the details given
+in the family characteristics. The chief character is the attachment
+of the posterior end by means of a single, longer or shorter, stalk,
+which contains a highly contractile thread easily distinguished
+in the living animal. Another character is the absence of colony
+formation. Contractile vacuole, single or double, usually connected
+with a sac-like reservoir. The macronucleus is invariably long and
+band-formed, with attached micronucleus. Fresh and salt water.
+
+So many species of _Vorticella_ have been described that the task of
+collecting data and of arranging the synonyms is extremely irksome
+and difficult. Stokes enumerates 66 species, inhabiting fresh and
+salt water, and several other new species have been added since his
+work. I am impressed with the fact that new species have been created
+without proper regard for the manifold variations which nearly all
+of the _Ciliata_ show, and I believe the 66 species might be safely
+reduced to 12 or 15.
+
+
+Vorticella patellina Mueller.  Fig. 59.
+
+Body campanulate, widest at anterior border, from which it tapers
+directly to the pedicle. The diameter of the peristome is a little
+larger than the length of the body. The ciliary disk is but little
+elevated. The cuticle is not striated and the body plasm is quite
+transparent. Length 52 mu.
+
+
+[Illustration: Fig. 59.--_Vorticella patellina_.]
+
+
+Vorticella marina Greeff.  Fig. 60.
+
+The body is conical but variable, and may he short or elongate, so
+that relative length and breadth offer no chance of identification.
+In general the body is campanulate. The distinguishing feature is the
+transverse annulation of the bell.
+
+Small, but common, and grows in small social groups. Length 35 mu.
+
+
+[Illustration: Fig. 60.--_Vorticella marina_.]
+
+
+Genus ZOOTHAMNIUM (Bory de St. Vincent 1824) Stein '38, '54.
+
+Colorless and highly contractile forms growing in small or large
+colonies. The form and structure of the individuals is not different
+from _Vorticella_. The colonies are usually richly branched upon
+the dichotomous plan and the entire colony is contractile. The main
+character is that with each division of the individual the stalk
+also divides, each daughter cell getting one-half of the parent stem.
+The stems therefore remain in communication, so that a simultaneous
+contraction results, and the colony as a whole is withdrawn. In some
+species so-called macrogonidia, or larger sexual individuals, are
+developed alongside the usual ones. Fresh and salt water.
+
+
+Zoothamnium elegans D'Udekem '64?  Fig. 61.
+
+The bodies are variable--peristomial border widely dilated, tapering
+and attenuate posteriorly. The pedicle is slender, smooth, and
+transparent, and branches sparsely at its distal extremity. There
+are but few zooids (3 to 4). The ciliary disk projects conspicuously
+beyond the peristomial border. The pharyngeal cleft is very distinct
+and extends beyond center of body. Length of body 80 mu.
+
+
+[Illustration: Fig. 61.--_Zoothamnium elegans_.]
+
+
+Genus COTHURNIA (Ehr. '31) Clap. & Lach. '58.
+
+Colorless forms of medium size-in some cases they may be green
+by Zoochlorella. The general structure is similar to that of
+_Vorticella_, but the individuals are elongate and occupy houses. The
+macronucleus is invariably long and band-form. The distinguishing
+character is the colorless or brownish lorica of quite variable form
+but always attached. These houses may be finger-formed, with widened
+center, or widened mouth, or constricted mouth, and the like.
+Ring-formed swellings are frequently developed. Sometimes the mouth
+becomes twisted and the lorica is therefore bilateral. The houses
+are attached either directly to some foreign object or by means of
+a short stalk. The animals are similarly fastened to the lorica,
+sometimes directly, sometimes by means of a short stalk. When they
+contract they draw back to the bottom of the lorica; when expanded
+they usually stretch out of the mouth opening. In some forms there
+is an operculum, by means of which the opening of the shell can be
+closed when the animal is retracted. Fresh and salt water.
+
+The number of species of _Cothurnia_ has become so great that the
+difficulty in placing forms is almost sufficient to discourage the
+systematist; as Buetschli well remarks, the variations in the theca
+have been made the basis of new species so many times that the
+genus is almost as confused as _Difflugia_ among the rhizopods or
+_Campanularia_ among the hydroids. The length of cup, of stalk,
+the presence of annulations on stalk or cup, etc., have given rise
+to many specific names, the majority of which I believe can be
+discarded. According to such differentials the same branch of an alga
+holding a hundred specimens of _Cothurnia crystallina_ yield 10 or 12
+species, whereas they are merely growth stages of one and the same
+form.
+
+
+Cothurnia crystallina Ehr.  Fig. 62.
+
+Synonyms: _Vaginicolla crystallina_ Ehr., Perty, Eichwald; _V.
+grandis_ Perty; _V. pedunculata_ Eichwald; _Cothurnia crystallina_
+Claparede & Lachmann, D'Udek.; _C. gigantea_ D'Udek; _C. maritima_,
+_C. crystallina_ Cohn; _C. grandis_ Meresch.
+
+The form of the cup shows the greatest differences; sometimes it is
+cylindrical, sometimes elongate thimble-shape, sometimes pouch-shape,
+corrugated or smooth on the sides, and wavy or smooth on border.
+Frequently the basal part becomes stalk-like, but this is very short.
+When present, the stalk may or may not have a knob-like swelling. The
+animal within the cup may or may not be borne on a stalk, and this
+stalk may or may not be knobbed. The cups are colorless or brown. The
+animal is very contractile and may stretch half its length out of the
+cup or retract well into it. There is no operculum. The length of the
+cup varies from 70 mu to 200 mu (_C. gigantea_; _Vag. grandis_, etc.).
+From Entz.
+
+There is nothing to add to Entz's characterization of this species,
+which is found both in fresh and salt water. The variability of the
+cup and stalk is quite noticeable in the Woods Hole forms.
+
+
+[Illustration: Fig. 62.--_Cothurnia crystallina_.]
+
+
+Cothurnia imberbis Ehrenberg, var. curvula Entz.  Fig. 63.
+
+Synonyms: _C. imberbis_ Kent et al.; _C. curvula_ Entz; _C. socialis_
+Gruber?
+
+The lorica is swollen posteriorly, narrowest at the oral margin, bent
+on its axis and is supported on a short stalk. It is perfectly smooth
+and without annulations. The animal itself has no definite stalk.
+When fully expanded the animal emerges but slightly from the margin
+of the cup. Fresh and salt water. On red algae. Dimensions of Woods
+Hole form: Cup 50 to 55 mu long; greatest diameter 22 mu; length of stalk
+4 to 5 mu.
+
+
+[Illustration: Fig. 63.--_Cothurnia imberbis_.]
+
+
+Cothurnia nodosa Claparede & Lachmann.  Fig.64.
+
+   A. Smooth cup.--_Cothurnia maritima_ Ehr., Eichwald, Stein, Kent.
+
+   B. Cross-ringed cup.--_C. pupa_ Eichwald, Stein, Cohn; _C. nodosa_
+      Cl & L.; _V. crystallina_ Entz '78; _C. pontica_ Meresch.,
+      Kent; _C. cohnii_ and _pupa_ Kent; _C. longipes_ Kellicott '94.
+
+The cup is elongated, swollen centrally, tapering at oral end
+and conical at base or rounded. Oral opening either circular or
+elliptical. Cross rings may or may not be present, and the cup is
+either smooth or annulate. Length of cup 70 mu to 80 mu. The stalk which
+supports the cup is extremely variable in length. The animal is borne
+upon a stalk of variable length within the cup.
+
+Entz states that the many variations which this species exhibits run
+into each other so gradually that he does not believe it wise to
+separate them. The Woods Hole forms which I found on algae of various
+kinds were nearly of a size, and did not vary much from the one
+figured. Kellicott '94 described a _Cothurnia_ from Woods Hole under
+the name of _C. longipes_, which I believe is only a long-stemmed
+variety of _C. nodosa_. My form has the following dimensions: Cup
+75 mu; cup stalk 38 mu; animal stalk 14 mu.
+
+
+[Illustration: Fig. 64.--_Cothurnia nodosa_.]
+
+
+KEY TO FAMILIES OF SUCTORIA.
+
+a. Unattached forms; ventral cilia        _Hypocomidae_
+   present; one suctorial tentacle
+
+b. Attached forms; thecate and            _Urnulidae_
+   athecate tentacles simple,
+   one or two in number
+
+c. Thecate; posterior end of cup          _Metacinetidae_
+   drawn out into stalk; walls
+   perforated for exit of tentacles
+
+d. Stalked or unstalked; globular;        _Podophryidae_
+   tentacles of different kinds, some     (2 genera *_Ephelota_,
+   knobbed, others pointed                *_Podophrya_)
+
+e. Naked or thecate; stalked or not;      _Acinetidae_
+   tentacles numerous, usually
+   knobbed and all alike
+
+f. Naked; athecate; tentacles             _Dendrosomidae_
+   numerous, all alike, knobbed and
+   grouped in tufts. They may be
+   simple or branched.
+
+g. Sessile forms resting on basal         _Dendrocometidae_
+   surface or on a portion raised
+   like a stalk; tentacles many;
+   short and knobbed; distributed
+   on apical surface or localized
+   on branched arms
+
+h. Stalked or sessile; tentacles          _Ophryodendridae_
+   long, rarely knobbed, supported
+   on proboscis-like processes
+
+   * Presence at Woods Hole indicated by asterisk.
+
+
+Genus PODOPHRYA Ehr. '33.
+
+(Buetschli '88; Stein '59; Perty '52; Cienkowsky '55; Quenn. '69;
+Hertwig '77; Maupas '81.)
+
+The body is globular, with tentacles radiating in all directions. The
+tentacles may be very short or very long. The stalk also is either
+short or long, and some species form stalks but rarely (_P. libera_).
+The macronucleus is centrally placed and globular to ovoid in form.
+The contractile vacuole is usually single. Reproduction takes
+place by division; the distal half developing cilia and becoming a
+swarm-spore. Fresh and salt water.
+
+
+Podophrya gracilis, n. sp.  Fig. 65.
+
+Of all the _Podophrya_ that have been described not one approaches
+this minute form in the relative length of the stalk. The body is
+spherical and is covered with short capitate tentacles. The stalk is
+extremely slender, bent, and without obvious structure. There are
+one or two contractile vacuoles in the distal half of the body. The
+nucleus is small and is situated near the insertion-point of the
+stalk. Reproduction not observed. Diameter of body 8 mu; length of
+stalk 40 mu. Only one specimen seen.
+
+
+[Illustration: Fig. 65.--_Podophrya gracilis_.]
+
+
+Genus EPHELOTA Str. Wright '78.
+
+(Buetschli '88; Ishikawa '96; Sand '98.)
+
+Small to medium-sized and large forms; colorless to brown. The body
+is globular or oval or wedge-shape, sometimes quadrangular. The stalk
+is variable, sometimes 1 mm. in length. The diameter of the stalk
+increases from the point of attachment to the body of the animal;
+it is usually striated either longitudinally or transversely, or
+both. The tentacles are of two kinds and are usually confined to
+the anterior half of the body. Some are long and sharp-pointed
+and adapted for piercing; others are short, cylindrical, usually
+retracted and capitate, adapted for sucking. Contractile vacuoles
+vary from one to many. The macronucleus is nearly central in position
+and usually of horseshoe shape, but is frequently branched and
+irregular. Reproduction is accomplished by external multiple budding,
+usually from the anterior half of the body. Salt water.
+
+
+Ephelota coronata Str. Wright.  Fig. 66.
+
+Synonyms: _Hemiophrya gemmipara_ S. K.; _Podophrya gemmipara_
+Hertwig.
+
+The body is spheroidal, ovate, or pyriform, with numerous
+sharp-pointed tentacles and a few straight, uniform tentacles. The
+stalk is about three times the length of the body and tapers from its
+widest part at the insertion in the body to the narrowest part at the
+point of attachment. It may or may not be longitudinally striated.
+This is one of the commonest of the _Suctoria_ found at Woods Hole.
+It is usually present on Campanularian hydroids, but may be found on
+algae and Bryozoa.
+
+Length of body 90 mu to 200 mu.
+
+
+[Illustration: Fig. 66.--_Ephelota coronata_.]
+
+
+Genus ACINETA Ehr. '33, Buetschli '88.
+
+(Stein '54, '59; Claparede & Lachman '58; Quennerstedt '67; Hertwig
+'76; Mereschowsky '79; Entz '84; Kent '81; Maupas '83; Gruber '84;
+Gourret & Roeser '86, and others.)
+
+Small to medium-sized forms. The distinguishing feature is that the
+stalk is swollen at the distal extremity to form a cup or basin in
+which the animal rests. The cup may be developed until the body is
+nearly inclosed. The macronucleus is spherical or band form. The
+contractile vacuole is usually single. Budding, so far as known, is
+endogenous. Fresh and salt water.
+
+
+Acineta divisa Fraipont '79.  Fig. 67.
+
+This extremely graceful form is common on Bryozoa at Woods Hole. The
+cup is shaped like a wine glass and is specifically characterized by
+a cup-formed membrane upon which the animal rests. The animal thus
+has the appearance of being suspended on the edge of the cup. The
+stalk is slender and about 4 times the length of the body. The
+tentacles are all capitate and distributed, and about 2-1/2 times the
+body length. They sway back and forth very slowly. The nucleus is
+spherical and central in position. The contractile vacuole lies near
+the periphery.
+
+Length of body 27 mu; of stalk 100 mu; of extended tentacle 65 mu.
+
+
+[Illustration: Fig. 67.--_Acineta divisa_.]
+
+
+Acineta tuberosa Ehr.  Fig. 68.
+
+Large forms of _Suctoria_ with tentacles arranged in fascicles. The
+stalk is variable in length and the cup is frequently so delicate
+that it can barely be made out. A specific characteristic is the
+break in continuity of the cup at different points, and through these
+places the tentacles emerge in bundles. The tentacles are capitate
+and in the Woods Hole form, 15 in number in each of the two bundles.
+The endoplasm is granular and yellowish in color. The coloring matter
+is frequently arranged in patterns. The nucleus is spheroidal. The
+contractile vacuole is in the anterior third of the body about midway
+between the bundles of tentacles. Reproduction not observed.
+
+Length of body 330 mu.
+
+
+[Illustration: Fig. 68.--_Acineta tuberosa_.]
+
+
+Genus TRICHOPHRYA Clap. & Lach. '58.
+
+(See Kent '81; Entz '84; Buetschli '88; Sand 1901.)
+
+Small forms to medium size; no cups or stalks. The body is spherical
+to elongate, usually, however, more or less irregularly lobed and
+changeable. The tentacles are in fascicles which are usually borne
+upon lobed or swollen places. The body is always more or less spread
+out. Contractile vacuoles variable. The macronucleus is spherical,
+elongate, band-formed or horseshoe-shaped. Reproduction takes place
+by endogenous budding, and the swarm spores are flat or lenticular
+with a distinct ciliary girdle. They are frequently parasitic. Fresh
+and salt water.
+
+
+Trichophrya salparum Entz '84.  Fig. 69.
+
+Buetschli '88; Schewiakoff '93; _Trichophrya ascidiarum_ Lachmann '59;
+Rene Sand 1901.
+
+The body is somewhat cup-form, with a large, flat base. The anterior
+border is rounded, each of the ends being somewhat truncate and
+carrying a bundle of tentacles all capitate and similar. These may be
+continued internally as far as the nucleus (Sand). The cytoplasm is
+uncolored, but may contain some brilliant granules. The nucleus is
+granular, and spherical, band or horseshoe formed.
+
+
+[Illustration: Fig. 69.--_Trichophrya salparum_.]
+
+
+This species was found by Dr. G. Hunter on the branchial bars of the
+Ascidian _Molgula manhattensis_, where great numbers of them are
+often parasitic.
+
+
+
+
+LIST OF REFERENCES.
+
+
+
+
+
+AUERBACH, L. '54. Ueber Encystierung von Oxytricha pellionella. Zeit.
+      wiss. Zool., V, 1854.
+
+---- '55. Ueber die Einzelligkeit der Amoeben. Zeit. wiss. Zool.,
+      VII, 1855.
+
+BALBIANI E. G. '61. Recherches sur les phenomenes sexuelles des
+      Infusoires. Jour. de la physiol:, IV, 1861.
+
+---- '85. Sur un Infusoire parasite du sang de l'Aselle aquatique.
+      Rec. zool. Suisse, II, 1885.
+
+BERGH, R. S. '79. _Tiarina fusus_ Cl. & Lach. Vid. Med. f. d. Nat.
+      Foren. Kjobenhavn.
+
+---- '82. Der Organismus der Cilioflagellaten.  Morph. Jahr., VII, p.
+      177.
+
+BRADY, H. B. '79. Report on the Foraminifera dredged by H. M. S.
+      _Challenger_ during the years 1873-1876. Challenger Reports,
+      Zoology, IX.
+
+BRANDT, K. '96. Die Tintinnodeen. Bibliot. Zoolog., XX, 1896.
+
+BUETSCHLI, O. '76. Studien ueber die ersten Entwickelungsvorg. der
+      Eizelle, die Zelltheilung, und die Conjugation der Infusorien.
+      Abhand. der Senck. naturf. Ges. Freiburg, X, 1876.
+
+---- '83-'88. Die Protozoen. Bronn's Klassen u. Ord. des Tierreichs.
+
+CARPENTER, W. B. '56. Researches on the Foraminifera. Phil. Trans.
+      (2), p. 547.
+
+CARTER, H. J. '56. Notes on the fresh-water Infusoria of the island
+      of Bombay. Ann. Mag. Nat. Hist. (2), XVIII.
+
+---- '63. On the coloring matter of the Red Sea. Id. (3), XI.
+
+---- '63a. On _Amoeba princeps_ and its reproductive cells. Id. (3),
+      XII.
+
+---- '64. On fresh-water Rhizopods of England and India. Id. (3),
+      XIII, p. 13.
+
+---- '65. On the fresh- and salt-water Rhizopods of England and
+      India. Id. (3), XV, p. 277.
+
+CIENKOWSKY, L. '55. Bemerkungen ueber Stein's Acinetenlehre. Bull.
+      Phys. Math. Acad., St. Petersburg, XIII, p. 297 (also in Ann.
+      Mag. Nat. Hist. (3), XIII).
+
+---- '55. Ueber Cystenbildung bei Infusorien. Zeit. wiss. Zool., VI,
+      p. 301.
+
+---- '61. Beitraege zur Kenntniss der Monaden. Arch. f. mik. Anat., I,
+      1865, p. 203.
+
+CLAPAREDE, E. '54. On _Actinophrys sol_. Ann. Mag. Nat. Hist. (2),
+      XV, 1854.
+
+---- '60. Recherches sur les annelides, etc., observes dans les
+      Hebrides. Mem. Soc. phys. d'hist. nat., Geneve, XVI, 1860.
+
+---- '67. Miscellanees zoologiques. Ann. d. sc. nat. zool. (5), VIII,
+      1867.
+
+CLAPAREDE ET LACHMANN '58-'60. Etudes sur les Infusoires et les
+      Rhizopodes. Mem. Inst. genevoise, V, VI, VII.
+
+COHN, F. '54. Beitraege z. Entwicklungsges. der Infusorien. Zeit.
+      wiss. Zool. III, 1851; IV, 1853.
+
+---- '57. Ueber Fortpflanzung von _Nassula elegans_ Ehr. Zeit. wiss.
+      Zool., IX, 1857, p. 143.
+
+COSTE, M. '64. Developpement des Infusoires cilies dans une
+      maceration de foin. Ann. d. ac. nat. zool.(5), II.
+
+DADAY, E. v. '86.  Ein kleiner Beitrag der Infusorien-Fauna des
+      Golfes v. Neapel. Mitt. Zool. St. Neap., VI, p. 481.
+
+---- '88. Monographie der Familie der Tintinnodeen. Mitt. Zool. St.
+      Neap., VIII, p. 473.
+
+DAVIS, J. '79. On a new species of Cothurnia. Jour. Roy. Mic. Soc.,
+      II, 1879.
+
+DUJARDIN, F. '35. Recherches sur les organismes inferieures. Ann. d.
+      sc. nat. zool. (2), IV, p. 343.
+
+---- '41. Histoire naturelle des Zoophytes infusoires. Paris, 1841.
+
+EHRENBERG, C. G. '31. Ueber die Entwickelung und Lebensdauer d.
+      Infusionsthiere. Abhand. d. Berlin Ak., 1831, p. 1.
+
+---- '38. Die Infusionsthierchen als vollkommne Organismen. Leipzig,
+      1838.
+
+ENGELMANN, Th. W. '78. Zur Physiologie der Contractilen Vacuolen der
+      Infusionsthiere.  Zool. Anz., I, p. 121.
+
+ENTZ, G. '84. Ueber Infusorien d. Golfes v. Neapel. Mitt. Zool. St.
+      Neap., V, p. 289.
+
+---- '85. Zur naheren Kenntniss der Tintinnodeen. Mitt. Zool. St.
+      Neap., VI, p. 185.
+
+FABRE-DOMERGUE, P. '85. Note sur les Infusoires cilies de la baie de
+      Concarneau. Jour. d. l'anat. et de la phys., XXI, p. 554.
+
+---- '91. Materiaux pour servir a l'histoire des Infusoires cilies.
+      Ann. d. mic., III, 1890-91, p. 49.
+
+FOL, H. '83. Further contribution to the knowledge of the
+      Tintinnodea. Ann. Mag. Nat. Hist. (5), XII, p.73.
+
+FRANCE, R. H. '97. Der organismus der Craspedomonaden. Budapest.
+
+FROMENTEL. E. DE. '74. Etudes sur les microzoaires, etc. Paris, 1874.
+
+GOURRET ET ROESER. '88. Contributions a l'etude des Protozoaires de
+      la Corse. Arch. d. biol., VIII  p. 139.
+
+GREEFF, R. '66. Ueber einige in der Erde lebende Amoeben und andere
+      Rhizopoden. Arch. f. mik. Anat., II, p. 299.
+
+---- '70. Untersuchungen ueber den Bau u. d. Naturgeschichte d.
+      Vorticellen. Arch. f. Naturges., XXXVI, XXXVII.
+
+---- '71. Ueber die Actinophryens oder Sonnenthierchen des
+      Suessenwassers als echte Radiolarien. Sitz. Ber. d. Niederrh.
+      Ges. i. Bonn, XXVIII, p. 4.
+
+---- '75. Ueber Radiolarien u. Radiolarienartige Rhizopoden des
+      Suessenwassers 2.  Arch. f. mik. Anat., XI.
+
+---- '88. Studien ueber Protozoen. Sitz. Ber. Ges. z. Bef. d. ges.
+      Nat., Marburg, 1888, p. 91.
+
+GRENACHER, H. '68.  Ueber _Actinophrys sol_ Ehr. Verh. phys.-med.
+      Ges. Freiburg (n. F.), I.
+
+GRUBER, A. '83. Beobachtungen an _Chilodon curvidentis_ n. sp.
+      Festschr. 56. Vers. Deutsch. Naturf. gewid. v. d. Naturf. Ges.
+      Freiburg, II, p. 1.
+
+---- '84. Die Protozoen des Hafens v. Genua. Nova Act. d. K.
+      Leop.-Car. Deutsch. Akad. d. Naturf., XLVI, p. 475.
+
+---- '87. Ueber der Bedeutung der Conjugation bei den Infusorien.
+      Ber. d. Naturf. Ges. Freiburg, II, p. 31.
+
+HAECKEL, E. '73. Zur Morphologie der Infusorien.  Jena Zeit., VII, p.
+      516.
+
+HERTWIG, R. '76. Ueber _Podophrya gemmipara_, nebst Bemerkungen zum
+      Bau u. d. systemat. Stellung d. Acineten. Morph. Jahr., IV,
+      p. 20.
+
+HERTWIG U. LESSER. Ueber Rhizopoden u. denselben nahe stehende
+      Organismen. Arch. F. mik. Anat., X, Suppl., p. 35.
+
+HUXLEY, T. H. '57. On Dysteria, a new genus of Infusoria. Jour. Mic.
+      Sci., V, p. 78.
+
+ISHIKAWA, C. Ueber eine in Misaki vorkommende Art v. Ephelota, etc.
+      Journ. Coll. Sci. Imp. Univ. Tokyo, Japan, X, pt. 2.
+
+JAMES-CLARK, H. '66. On the Spongiae ciliatae as Infusoria flagellata,
+      etc. Mem. Bost. Soc. Nat. Hist. (3), I, p. 1.
+
+KENT, W. SAVILLE. '81. Manual of the Infusoria. London, 1881.
+
+KLEBS, G. '84. Ein kleiner Beitrag z. Kenntniss d. Peridineen. Bot.
+      Zeit., XLII, p. 721.
+
+---- '92. Flagellaten Studien 1. Zeit. wiss. Zool., LV.
+
+LABBE, A. '95. Sur les Protozoaires marins de Roscoff. Arch. d. zool.
+      exper. (3), N. et R., p. XIV.
+
+LAUTERBORN, R. '94. Beitraege z. Suesswasserfauna der Insel Helgoland.
+      Wiss. Meeresunt. Komm. wiss. Unt. d. Meere Kiel (2), I, p. 215.
+
+LEIDY, J. '77. Remarks upon Rhizopods and notice of a new form. Proc.
+      Ac. Sci. Phila., 1877, p. 293.
+
+---- '79. Fresh water Rhizopods of North America. Washington, 1879.
+
+LIEBERKUEHN, N. '56. Ueber Protozoen.  Notes from a letter to C. Th.
+      v. Siebold. Zeit. wiss. Zool., VIII, p. 307.
+
+MAUPAS, E. '81. Contributions a l'etude des Acinetiens. Arch. d.
+      zool. exper. (1), IX, p. 299.
+
+---- '83. Contributions a l'etude morphologique et anatomique des
+      Infusoires cilies. Id. (2), I.
+
+---- '83a. Les sucto-cilies de M. Mereschowsky. Comp. Ren., XCV, p.
+      1381.
+
+---- '88. Recherches experimentales sur la multiplication des
+      Infusoires cilies. Arch. d. zool. exper. (2), VI, p. 165.
+
+MERESKOWSKY, C. '78. Studien ueber Protozoen des nordlichen Russland.
+      Arch. f. mik. Anat., XVI, p. 163.
+
+---- '81. On some new or little-known Infusoria. Ann. Mag. Nat. Hist.
+      (5), VII, 1881.
+
+MOEBIUS, K. '88. Bruchstuecke einer Infusorienfauna der Kieler Bucht.
+      Arch. f. Naturg., 1888.
+
+PECK, J. I. '93. On the food of the menhaden. Bull. U. S. Fish Com.,
+      1893, p. 113.
+
+---- '95. The sources of marine food. Bull. U. S. Fish Com., 1895, p.
+      351.
+
+PERTY, M. '49. Mikrosk. Organ. der Alpen u. d. Italien. Schweiz.
+      Mitt. d. Naturf. Ges. in Bern, 164-165.
+
+---- '52. Zur Kenntniss kleinster Lebensformen, etc., Bern.
+
+POUCHET, G. '83; '85. Contributions a l'histoire des Peridiniens
+      marins. Jour. de l'anat. et de la phys., XIX, XXI.
+
+QUENNERSTEDT, A. '65; '67; '69. Bidrag till Sveriges Infusorie-fauna.
+      Lunds Univ. Aersskrift, II, IV, VI.
+
+SAND, R. 1901. Etude monographique sur le groupe des Infusoires
+      tentaculiferes. Ann. d. la Soc. belge de microscopie, XXIV,
+      XXV, XXVI.
+
+SCHAUDINN, F. '95. Die Heliozoen. Das Tierreich, 1895.
+
+SCHEWIAKOFF, W. '89. Beitraege z. Kenntniss der Holotrichen Ciliaten.
+      Bib. Zool., V, p. 1.
+
+---- '93. Ueber einige ecto- u. ento-parasitische Protozoen der
+      Cyclopiden. Bull. Soc. nat. Moscou, 1893. I.
+
+SCHUETT, F. '95. Die Peridineen d. Plankton-Expedition, 1. Kiel u.
+      Leipzig.
+
+SCHULTZE, F. E. '74; 75. Rhizopodenstudien. Arch. f. mik. Anat., X,
+      XI, XIII.
+
+SCHULTZE, M.  '62. Ueber d. Organismus d. Polythalamien. Leipzig,
+      1862.
+
+SHEVYAKOV ?. '96. Monograph on _Holotrichous ciliates_. (In Russian.)
+      Mem. of the St. Petersburg Acad., VII.
+
+STEIN, F. '59; '78; '83. Der Organismus der Infusionsthiere. I.
+      Infusoria, '59; II. Infusoria, '78; III. Flagellata, '83.
+
+---- '49. Untersuchung ueber die Entwicklungs d. Infusorien. Arch. f.
+      Natur., I, p. 92.
+
+---- '54. Die Infusionsthiere auf ihre Entwicklungsgeschichte
+      untersucht. Leipzig, 1854.
+
+---- '60. Ueber _Leucophrys patula_ u. ueber 2 neue
+      Infusoriengattungen Gyrocoris u. Lophomonas. Sitz. Ber. d.
+      K.-boehm. Ges. d. Wiss. d. Prag, 1860, p. 4.
+
+---- '64. Ueber die neue Gattung Epiclintes. Id., 1864, I.
+
+STERKI, V. '78. Beitraege z. Morphologie der Oxytrichinen.  Zeit.
+      wiss. Zool., XXXI, p. 29.
+
+---- '98. On the classification of ciliate Infusoria. Amer. Natur.,
+      XXXII, p. 425.
+
+STEVENS, N. M. 1901. Studies on ciliate Infusoria.  Proc. Calif.
+      Acad. Sciences, III, 1.
+
+STOKES, A. C. '84. Notices of some new parasitic Infusoria. Amer.
+      Nat., XVIII, p. 1081.
+
+---- '85. Some apparently undescribed Infusoria from fresh water.
+      Id., XIX, p. 18.
+
+---- '87. Some new hypotrichous Infusoria from American fresh waters.
+      Ann. Mag. Nat. Hist. (5), 20.
+
+TATEM, T. G. '67. New species of microscopic animals.  Q. J. M. S.
+      (n.s.), VII, p. 251.
+
+VEJDOWSKY, F. '79. Monographie der Enchytraeiden.  Prag, 1869.
+
+WALLENGREN, H. '94. Studier ofver ciliata Infusorier, 1. Slagtet
+      Lichnophora. Lund, 1894.
+
+WALLICH, G. C. '63. Observations on an undescribed indigenous Amoeba.
+      Ann. Mag. Nat. Hist. (3), XI, XII.
+
+WESTON, J. '56. On the _Actinophrys sol_. Q. J. M. S., IV, p. 116.
+
+WRZESNIOWSKI A. '61. Observations sur quelques Infusoires. Ann. d.
+      sc. nat. zool. (6), XVI.
+
+---- '69. Ein Beitrag zur Anatomie der Infusorien. Arch. f. mik.
+      Anat., V, p. 25.
+
+---- '70. Beobachtungen ueber Infusorien a. d. Umgebung v. Warschau.
+      Zeit. wiss. Zool., XX, p. 467.
+
+
+
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