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diff --git a/43417-0.txt b/43417-0.txt new file mode 100644 index 0000000..cde106a --- /dev/null +++ b/43417-0.txt @@ -0,0 +1,13978 @@ +*** START OF THE PROJECT GUTENBERG EBOOK 43417 *** + +Transcriber's note: A few typographical errors have been corrected: they +are listed at the end of the text. + + * * * * * + + +[Illustration] + + 1. _Spondylus Americanus. (Young.)_ + + 2. _Nautilus pompilius. (Young.)_ + + _G. B. S. Jun^r. fecit._ + + * * * * * + + +A + +CONCHOLOGICAL MANUAL. + +BY + +G. B. SOWERBY, JUN. + +ILLUSTRATED BY UPWARDS OF SIX HUNDRED AND SIXTY FIGURES + + * * * * * + +SECOND EDITION. + +CONSIDERABLY ENLARGED AND IMPROVED. + + * * * * * + +LONDON: + +HENRY G. BOHN, YORK STREET, COVENT GARDEN. + +MDCCCXLII. + + * * * * * + + +PREFACE TO THE FIRST EDITION. + +It may be necessary in introducing this little volume, to state, that it is +strictly conchological, and that it is compiled for the use not only of +those who wish to acquire an elementary acquaintance with the subject, but +also of authors and others, who, desirous of extending their knowledge and +pursuing their researches, require a book of reference, containing a +general outline of what has been done by those who have trodden the same +path before them. It has been thought advisable, for general convenience, +to arrange the principal part of the information in alphabetical order: +adding tables of the systems of Lamarck and De Blainville, to facilitate +the systematic pursuit of the science. + +Persons of the class first alluded to, will find great assistance in the +explanation of technical words, their application being further +illustrated, in most cases, by a reference to the figures; and, although +they might have been multiplied, it is trusted that enough are given for +every useful purpose. + +The definition of the Classes, Orders, Families, and Genera, in the system +of De Blainville, and a tabular view, are presented for the use of those +who prefer it, or who wish to compare it with that of Lamarck. + +In the explanation of the figures, will be found a systematic arrangement +of shells, according to Lamarck, including the names of genera established +or proposed since the publication of his system. The descriptions of +established genera have been rendered as concise and clear as possible. It +is hoped that no essential characters are omitted, and that those living +authors, whose proposed generic distinctions have been passed over in a few +words, will not have to complain of want of justice in the attempt to +interpret their meaning. + +In most cases the generic name will be found accompanied by its derivation. +This has been done, in the hope of assisting the memory by associating the +meaning of a term with some peculiarity in the thing described. At the end +of each description of a genus, some general observations occur, pointing +out the principal character which distinguishes it from others, to which it +is nearly allied; and also stating the geographical or geological +distribution and habits of the animal. + +The above descriptions and definitions are illustrated by a series of +plates, containing above 500 etchings of nearly as many proposed or +established genera, arranged in Lamarckian order, so as to show at a glance +all the generic forms of each family. And, although from their number, they +could not be very highly finished, it is hoped that they will be found +characteristic. + +The compiler cannot replace his pen without acknowledging, with filial +gratitude, the kind assistance of one who has sacrificed much of his time +in bringing his knowledge and experience to bear upon the correctness and +utility of this humble attempt to remove some of the difficulties to which +the commencement of this, as well as of every other study, is exposed. + +PREFACE TO THE SECOND EDITION + +The favourable reception and rapid sale of the first edition of the +Conchological Manual having rendered a second necessary, the Author takes +this opportunity of explaining the nature of the alterations which have +been made. In doing this, he has to thank his friends for their +suggestions, which, together with his own increased knowledge and +experience, enable him to present a more complete and satisfactory work to +the scientific public. + +For the further convenience of those who are studying the rudiments of the +science, an entirely new Introduction is given, in which, commencing with +the structure and gradual developement of the shell, the author has +endeavoured to explain the general principles of Conchology in systematical +order. This Introduction is illustrated by 100 wood-cuts, which will be +found greatly to assist the Student. + +The definitions have been rendered more full and complete than before, and +the Author has profited by some manuscript notes communicated by a +scientific friend, to whom he desires to present his humble +acknowledgments. Upwards of four hundred explanations have been given of +words which did not appear in the former edition, three-fourths of which +are of generic and subgeneric names. + +A large number of notes, referring to the geographical distribution of the +genera, have been added from the pen of Mr. G. B. Sowerby, Senior. + +The plates have been carefully improved; and three, containing upwards of +eighty figures, have been added. + +On the whole, it will be found that the amount of matter has been nearly +doubled; all the defects, as far as they have been discovered, have been +removed, and every means used of making the present edition as useful as +possible. + + * * * * * + +NAMES OF AUTHORS ABBREVIATED. + + _Adans._ Adanson. Author of "Voyages du Senegal." + + _Bl._ Blainville. Author of "Manuel de Malacologie et de + Conchyliologie," &c. + + _Brod._ W. J. Broderip, Esq. Author of various descriptions of Shells + in the Zoological Journal, &c. + + _Brongn._ Brongniart. Author of "Memoire sur les terrains du Vicentin, + d'Italie, de France, et d'Allemagne," &c. + + _Brug._ Brugière. Author of "Dictionaire des Vers testacés, dans + l'Encyclopédie," &c. + + _Cuv._ The late Baron Cuvier. Author of "Regne Animal," &c. + + _Defr._ Defrance. Contributor to the "Annales des Sciences Naturelles," + &c. + + _Desh._ Deshayes. Author of "Coquilles fossiles des environs de Paris," + &c. + + _D'Orb._ D'Alcide D'Orbigny. + + _Drap._ Draparnaud. Author of "Histoire Naturelle des Mollusques + terrestres et fluviatiles de la France," &c. + + _Fer._ De Ferussac. Author of "Histoire Naturelle des Mollusques + terrestres et fluviatiles," &c. + + _Flem._ Fleming. + + _Gmel._ Gmelin. Author of an edition of Linnæus's "Systema Naturæ," &c. + + _Guild._ Rev. Lansdown Guilding. + + _Hübn._ Hübner. + + _Humph._ The late George Humphrey. + + _Lam._ Lamarck. Author of "Animaux sans Vertebres," &c. + + _Lin._ Linnæus. Author of "Systema Naturæ," &c. + + _Mont._ Montague. Author of "Testacea Britannica," &c. + + _Montf._ Montfort. Author of "Histoire Naturelle des Mollusques," &c. + + _Müll._ Müller. Author of "Vermium terrestrium et fluviatilum," + "Zoologiæ Danicæ," &c. + + _Ranz._ Ranzani. Author of "Considerations sur les Balanes," &c. + + _Schum._ Schumacher. + + _Sow._ Sowerby. The late James. Author of "Mineral Conchology," &c. + George Brettingham, Senr., "Genera of Shells," "Species Conchyliorum," + &c. G. B. Jun. "Conchological Manual," "Conchological Illustrations," + "Thesaurus Conchyliorum," Descriptions of New Shells in the Zoological + Proceedings, &c. + + _Sw._ Swainson. Author of "Zoological Illustrations," "Exotic + Conchology," "Lardner's Cabinet Cyclopedia," &c. + + _Turt._ Turton. Author of "British Shells." + + * * * * * + + +INTRODUCTION. + +The Science of Conchology affords a very delightful and instructive +amusement for the leisure hours of those who, retiring occasionally from +the gaieties of fashionable life, seek pleasure in the quiet contemplation +of some of the smaller, but not less wonderful operations of creative +wisdom. And, although the study of shells would be more complete, and rank +higher in the scale of philosophical pursuits, were it always accompanied +by that of the animal inhabiting them, it nevertheless presents means of +intellectual gratification, to many who cannot follow it beyond the cabinet +and the boudoir. These may examine with admiration and mental improvement, +the beautiful colouring and architecture of these wonders of the deep, they +may exercise their taste and judgment in the selection and arrangement of +specimens, and their discrimination in detecting and appreciating the +distinctions upon which the arrangement is founded. + +It is but little that can be known of the subject without forming a +collection of greater or less extent; for, as it would be uninstructive +merely to delight the eye with the bright colours and elegant form of +shells, without possessing correct information respecting them, so it would +be insipid and useless to learn technicalities without being acquainted by +personal observation with the subjects to which they are applied. The first +endeavour should, therefore, be to obtain a few shells as examples of the +larger divisions, and, when these are understood, to proceed with the +smaller groups, until a collection be formed to represent as many generic +forms as possible. It may be as well here to advise those who are forming a +collection to be very particular in every practicable instance to have the +shells properly named at the time of purchasing; as it will save much +trouble, and materially assist in the attainment of the desired object. To +this end, recourse should be had to those naturalist tradesmen, who unite +the attainment and diffusion of real scientific knowledge with their +commercial pursuits. + +Supposing, however, that the person who desires to learn the science, +possesses a small parcel of unarranged and unnamed shells, without any +previous acquaintance with the subject, the following introductory +explanations, are drawn up with the view of enabling him, without further +assistance, to obtain a general insight into its principles, equal to that +of those who have studied it long and laboriously. To effect this, he must +read them, carefully comparing the descriptions with the figures referred +to, and with the specimens which he may have at command. + +After describing the nature of the science and defining its objects, we +shall proceed to explain the structure of those objects, and the manner of +their growth. We shall then enter somewhat minutely into the principles of +classification, the distinctions upon which they are founded, and some of +the technical terms used to express them. After which we shall pass through +the arrangement of Lamarck, defining the general divisions adopted under +the terms of "_Classes_, _Orders_, and _Families_," as far as they are +capable of definition. The subdivision of the latter into _genera_ will +only be entered into so far as to enumerate the principal of them, the more +minute descriptions being reserved for the alphabetical part of the work. + +Let none be discouraged by the number of generic distinctions proposed and +adopted in modern times; for if well defined, they will be found to +facilitate rather than encumber the science. The knowledge of species must +be the foundation of every system, and the greater their number, the more +necessary it becomes to subdivide them; if, for instance, all the species +now known were to have been included in the 50 genera of Linnæus, a single +genus would have contained many hundreds of incongruous species, in which +case it would be much more difficult to remember them, than if they were to +be divided into a far greater number of genera. Every well marked division, +however arbitrary its limits, tends to simplify the subject, and to +facilitate the researches of the student. + +NATURE OF THE SCIENCE. + +Conchology is the study of shells, viewed and described as to what they are +either in themselves, or in relation to the soft, inarticulate animals +which produce them, and of which they form a part. These animals are called +MOLLUSCA, and perhaps the best general description of them will be found in +De Blainville's "Manuel de Malacologie et de Conchyliologie." The following +is a translation, "Animal in pairs, the body and its appendages soft, +inarticulate (not jointed), enveloped in a muscular skin, commonly called +the mantle, which is extremely variable in form, and has developed either +within or upon it a calcareous portion, consisting of one or several +pieces, commonly called a SHELL." + +The term Mollusca was formerly restricted to those soft animals which were +destitute of shells, although possessing in other particulars, the +characters described above, and it was used in order to distinguish them +from the TESTACEA, which were covered or internally supported by calcareous +parts. In the system of Linnæus, the soft portions are first arranged under +the general designation of "Vermes Mollusca," and described without regard +to the presence, absence, or character of the shells; and then the shells +are separately characterized under the appellation of "Vermes Testacea," +without any further notice of the animal, than an indication of the genus +to which it belongs; thus the animal of Cypræa is said to be a Limax, and +that of Tellina a Tethys. + +The nearest approach to correctness, and the most philosophical method of +study will be found in the modern system, adopted by Lamarck and his +followers, of observing these animals as a whole, and arranging them +according to the assemblage of characters which they present; of course +taking into consideration the existence or non-existence, form and +structure of the shell, on the same principle, which, in arranging the +vertebrated animals would lead us to study the hair, hoof, nails, claws, +&c. as well as the other parts. + +At the same time, it must be admitted that there are many private +collectors of Shells who would find it a difficult, if not impossible task +to study minutely and successfully the soft parts of the Mollusca. Ladies, +for instance, could not be expected to handle with pleasure and +perseverance, these fleshy substances, which in order to be preserved from +putrefaction, must be kept in spirits; and yet such persons may, with +improvement and advantage to their own minds, enjoy the interesting and +scientific amusement of studying and arranging the clean and beautiful +natural objects which are so easily preserved, and so exquisitely curious +in their structure. Let it also be remembered, that if shells had not been +rendered commercially valuable, by the zeal and emulation manifested by +_mere_ Conchologists for the possession of rare specimens, few travelling +merchants and sea captains would have thought them worthy of a corner in +their cabins. In this case, few specimens being brought to the country, the +more Philosophical Naturalist would have been left without the means of +obtaining materials to work upon, or of attracting public attention to his +favourite pursuit. + +On account of these and other considerations, it has been thought advisable +that the present undertaking should bear a purely conchological character. +The peculiarities of the shells alone being detailed for the assistance of +those who collect and study them, while at the same time, in deciding upon +their affinities and places, in the arrangement, it will be necessary to +take advantage of the conclusion to which those have arrived, who have +studied the animal in all its parts. And the conviction must be expressed, +that if ever a complete Natural System shall be formed it will result from +the labours of the last mentioned class of naturalists. + +DEFINITION OF A SHELL. + +Before entering minutely into the description of shells, it will be +necessary to distinguish from the true testaceous Mollusca two kinds of +animals which have formerly been associated with them. Of these, the first +is the class of CRUSTACEA, consisting of crabs, crayfish, &c. These differ +from shell-fish, not only in structure and chemical composition, but also +in the fact that the animal has jointed limbs, and that the substance of +the flesh is inseparable from the hard external covering, which invests +each particular joint as with a sheath; whereas the Molluscous animal is +but partially attached to its shell, from which it possesses the power of +partly withdrawing and returning. The second class is that to which the +sea-urchin, or Echinus, belongs, of which there are many genera and +species. The testaceous covering of Echini is composed of a number of small +pieces, placed edge to edge, forming a more or less globular external +covering to the flesh, which is supported in the centre by a number of +bones leaning upon each other in a pyramidal form. The _test_ is of a +fibrous texture, guarded on the outside with moveable spines, which turn on +ball and socket joints. + +A true shell is composed of one or more calcareous pieces, commonly called +valves, each piece formed by a series of layers, applied obliquely upon +each other, in such a manner that each new layer begins within, and +terminates a little in advance of the one before it. + +STRUCTURE AND GROWTH. + +We shall now endeavour to describe the manner in which the growth of each +separate valve, or each regularly formed shell, proceeds from the nucleus. + +Before the young animal has left the egg, if it be an _oviparous_ species, +or the body of the parent if _viviparous_, the nucleus of the shell is +generally formed, and specimens are sometimes preserved in which the young +shell is seen within the egg, as in the cut, fig. 1, 2; or adhering to the +inner surface of the full-grown shell by the dried mucus of the animal, as +seen in fig. 3. + +[Illustration: 1. Egg of a Bulinus. 2. The same broken, shewing the young +shell. 3. The young of a Paludina, as seen in the aperture of the shell.] + +In both cases, the nucleus is generally of a more horny and transparent +composition than the parts subsequently produced. As soon as the animal is +hatched, or, in other words, leaves the egg or body of the parent, of +course it begins to increase in size, and to require a corresponding +enlargement in the shell. To effect this, a small quantity of mucus +substance, secreted by the mantle of the animal, is deposited on the edge +of the aperture. When this is dry and become sufficiently hard, it is lined +by a more calcareous secretion; and these together form a new layer, which +is followed by others in succession; each new layer being larger than the +one that preceded it until the whole being complete, the full-grown animal +is invested with a shell commensurate with its own proportions. Thus from +the apex or nucleus the formation proceeds, as it were, downwards, taking +the shape of the part which secretes it, on which it is in a manner +moulded. + +The nucleus, or first formed portion, may for technical purposes be +considered, mathematically, as the apex of a spiral cone. And here it must +be observed, that whether the shell consist of one or several pieces, each +piece has a separate nucleus, and the process of formation is separately +repeated with each. The word cone is used for convenience, and its meaning +extended so as to include all those structures which commencing at a point +enlarge downwards. + +[Illustration: 4. Imaginary cone. _a._ Apex. _b._ Base. _l._ Lines of +growth.] + +From the apex, the next layer is deposited on its edge, and advancing +beyond it necessarily adds to its extent. Thus, suppose for the sake of +illustration, the part marked _a_ in the diagram, fig. 4, to represent a +nucleus, the cross lines (_l_) will shew the consecutive layers, which +enlarge their circle as they add to their numbers. This disposition of +shelly matter into layers is marked externally by concentric striæ, or +_lines of growth_, while on the inside the edges of the laminæ are +consolidated into a kind of enamel. If a perpendicular section of a solid +portion of a shell were magnified, it would present, in many instances, an +appearance resembling the diagram, fig. 5; _a_ may be taken to represent +the horny part of the layers which form the outer coating, named +"_Periostaca_," or "_Epidermis_;" the undulating line _b_, is formed by the +edges of the calcareous layers, and causes the striæ, or lines of growth, +which are often distinguishable on the surface of the shell; the space _c_ +is the middle part of those layers, and at _d_ they are consolidated into +the enamel which lines the interior. + +[Illustration: 5. Supposed section of a part of a solid shell.] + +In some species the layers are irregularly grouped together, and their +edges overlap each other, so that they are easily separable, and advancing +beyond each other, give a leafy appearance to the external surface. This +structure is termed _foliaceous_. A very familiar instance of this may be +observed in the common oyster. If a specimen of this shell be broken, the +substance will be seen to exhibit a degree of looseness, and a magnifying +glass will enable the student to trace distinctly the laminæ of which it is +composed. The accompanying representation of a magnified section (fig. 6) +will shew at _a_, the external surface, with the foliations or leaves; at +_b_, the parcels of layers which form them; and at _c_, the pearly +structure produced by their consolidation, and by the subsequently +deposited enamel which covers their external surface. + +[Illustration: 6. Section of an oyster shell enlarged.] + +CLASSIFICATION. + +The classification of shells, that is, their systematic arrangement into +_classes_, _orders_, _families_, _genera_ and _species_, cannot be made to +depend entirely upon the characters observable in them, viewed by +themselves; for this reason, that many similarly formed shells form the +habitations of animals perfectly distinct, and that many molluscous animals +are found to agree with each other in every respect but in the form of +their testaceous support. There are, however, many important distinctions +to be observed in the shells themselves, leading to the establishment of +many of those very divisions, which would afterwards be confirmed by an +examination of the soft parts. It is necessary to attend, as far as means +and opportunity will allow, to _all_ the points of difference, both in the +shell and in the animal, in order to form, and in some instances even to +appreciate, a generic or larger distinction. It will therefore be our +endeavour to explain the general principles upon which those distinctions +are formed, and the manner in which they are applied and expressed in +detail by scientific writers. + +NUMBER OF PIECES, OR INDEPENDENTLY FORMED PARTS. + +The first, most simple and obvious division of shells, is that which +results from the number of separate pieces composing them. Hence the +distinction implied by the terms UNIVALVE, or consisting of a single piece; +BIVALVE, or composed of two pieces; and MULTIVALVE, or composed of more +than two. For an example of _univalve_, take a common whelk; for a +_bivalve_, take a muscle or a scallop; and for a _multivalve_, the +barnacle, or balanus, found adhering to the common oyster. + +But although this arrangement may appear at first sight perfectly easy and +plain, some explanation will be necessary in order to guard the student +against understanding the above expressions in their strictest sense, +without qualification. Thus the univalves are said to consist of a single +piece, or spiral cone; but it would be more correct to speak of this piece +as forming either the whole or the principal part of the shell: for there +is in many instances, a much smaller flattened piece attached to the foot +of the animal, which being drawn in when it retires, closes the aperture as +with a kind of door, to which in fact the word valve might be very properly +applied; it is called however the OPERCULUM, and the little horny plate, +frequently drawn out by means of a pin from the aperture of a periwinkle, +will present a familiar example. + +[Illustration: Accessary valves of a Pholas.] + +The same may be said respecting the bivalves; for besides the principal +portions or valves of which the shell is composed, there are in many +species, one or two smaller separate portions, named "_accessary plates_" +by some authors. They are fixed by means of cartilages, on the back of the +hinge.--The engraving, fig. 7, represents the accessary valves of a species +of Pholas, which was on this account arranged by Linnæus with the +Multivalves. Nearly allied to the Pholades is a set of shells to which De +Blainville has given the name "_Tubicolæ_," or inhabitants of tubes. In +this case, the bivalve shell is connected with a testaceous tube or pipe, +to which it is attached either by one or by both valves, or in which it +lies attached only by the cartilages of the animal. In the genus +Aspergillum, the two small valves are soldered into the sides of the tube +in such a manner as to constitute a part of it. One of these shells, called +the Water-spout, might be taken up by a person not aware of its real +nature, and regarded as a pipe or tube prettily fringed, and nothing more; +but upon a closer examination, he would find the two valves, the points of +which are visible from the outside of the tube. + +HABITS--_Land, Fresh-water, or Marine Shells._ + +Another distinction, leading to important results in classification, is +that which is derived from the nature of the element breathed by the +Mollusc. And although this consideration belongs more especially to the +study of the animal itself, yet the habits of the animal materially +influence the structure of the shell. + +The TERRESTRIAL or LAND Molluscs live on land, breathe air, and feed on +plants and trees.--Those who find pleasure in horticultural pursuits will +at once call to mind a too familiar example of these Molluscs in the common +garden snail. The Land-shells are all univalves, and constitute a family in +the Lamarckian system under the name "_Colimacea_," or snails, +corresponding with the Linnean genus Helix.--They are generally light in +structure and simple in form. + +The AQUATIC, or Fresh-water Molluscs, such as the Planorbis, commonly +called the Fresh-water Snail; the Unio--known by the name of Fresh-water +Muscle, is found in ponds, ditches and rivers. The _epidermis_ of these is +generally of a thick, close-grained character, and they are subject to +corrosion near the umbones. There are but few genera of fresh-water shells +besides the Uniones, among bivalves, and the "Melaniana" among univalves. +Concerning the former it may be observed, that they are all pearly within, +and the colour of the thick horny coating embraces all the varieties of +brownish and yellowish green. + +The MARINE, or _sea-shells_, belong to all the classes and orders, and +include by far the greater number of species. They vary in the habits of +the animal, and consequently in the situations in which they are found. +Some are found buried in sand and marine mud, and are named "_Arenicolæ_" +or inhabitants of sand; others in holes of rocks and other hard substances, +then they are named "_Petricolæ_,"--some of these latter form the holes in +which they live by corroding or eating away the stone. A section of these +form the family of "_Lithophagidæ_," or stone-eaters, of Lamarck. Others, +again, take up their parasitical abode in the bodies of animals, and feed +upon their substance; as for instance, the Stylifer, which is found in the +vital part of star-fish, and Coronula, and Tubicinella, found buried in the +skin of the whale. + +LOCOMOTION--_Attached, Unattached._ + +A much more subordinate source of distinction arises from the freedom or +attachment of the shells. Some of them float or walk freely in their +natural element; others are fixed or attached to foreign bodies. Among +those which are attached, there is again a difference as to the mode of +attachment. Some are united to foreign bodies by means of a glutinating +substance, secreted by the animal, and joining part of the surface of the +shell to that of the stone, coral, or other substance. In this way shells +are fixed to each other in groups; this is the case with the Spondyli among +bivalves, and the Serpulæ among univalves. M. de Blainville applies the +term "_Fixæ_" to these shells. Others are kept in a particular place by +means of a _Byssus_ or Tendinous fibrous line or bunch of silky hairs, +acting as a cable, and allowing the Mollusc to ride as it were at anchor. +This Tendon is connected with some part of the animal from which it passes +through an opening or hiatus in the shell, as in the Terebratula and the +Mytilus. + +[Illustration] + +In the former, represented by the cut, fig. 8, the tendon passes through a +perforation in the upper valve; and in the latter, Mytilus, fig. 9, the +byssus passes out between the valves. + +Before proceeding to explain the characters of the different groups, +according to the modern system of classification, it may be desirable to +explain the terms by which the different parts and characters are +described, and to shew the manner in which the shells are measured. For +this purpose we shall treat of the general divisions separately. We begin +with + +UNIVALVE SHELLS. + +In considering Univalves merely with reference to their mathematical +construction, the first point demanding our attention is, whether they are +symmetrical or non-symmetrical, or, in other words, whether a straight line +drawn through the shell would divide it into two equal parts. The greater +part of univalves are non-symmetrical, being rolled obliquely on the axis; +but many are symmetrical, being rolled horizontally on the axis. The +Nautilus presents an illustration of the latter; the Snail is a familiar +example of the former. + +_Symmetrical Univalves._ + +[Illustration] + +In describing these it will be well to commence with the most simple form, +such as the Patella,--taking a conical species as an example. In this it +will be observed that there is no winding or curvature, but a simple +depressed cone, and that the line _a_, _p_, divides it into two equal +parts. + +The _anterior_, _a_, (_cut_, fig. 10) is known by the interruption of the +muscular impression which surrounds the central disc (_d._) This +interruption of the muscular impression is in the place where the head of +the animal lies in the shell. The impression itself is caused by the +fibrous muscle which attaches the animal to the shell. The apex (_a_) in +Patella, generally leans towards the anterior (_a_) part of the shell, and +away from the posterior (_p_); and this circumstance has caused some +mistakes, because in Emarginula the apex leans towards the posterior; and +students, instead of examining the muscular impression, which is the only +criterion, have only noticed the direction in which the apex turned, and +concluded that to be the anterior, towards which it inclined. The lines or +ribs running from the base to the apex of the shell, in the direction _r_, +are called _radiating_ lines; and those which encircle the cone in the +direction _c c_, from front to back, are very properly described as +_concentric_. The _length_ is measured from front to back in the line _e_; +the breadth, from side to side, in the line _b_; and the depth from the +apex to the base. + +Let it be observed that patelliform, or limpet-shaped shells are not all +symmetrical; Umbrella, Siphonaria, Ancylus, &c. will form exceptions, of +which we have yet to speak. And the learner may also be reminded that the +Limpets themselves are not _all_ regular in their form: for as they adhere +to rocks and other rough surfaces, and are so little locomotive, in many +instances they partake of the inequalities of the surface, and conform to +its irregularities. This adherence is not effected by any agglutinating +power in the animal, nor by any tendinous process like that described +above; but simply by means of the foot of the animal acting as a sucker. + +The next variation in symmetrical univalves is to be observed in the +tubular, curved form, the example of which will be the Dentalium, fig. 12. + +[Illustration: Dentalium Elephantinum.] + +This has an opening at the anterior termination _a_, called the aperture. +The opening at the posterior end (_p_) is named a fissure, or perforation. +The ribs running along the sides of the shell are _longitudinal_, or +radiating. And the lines round the circumference are _lines of growth_, or +_concentric_--each one having in succession, at earlier stages of growth, +formed the aperture. They are described as concentric, or transverse. + +_Symmetrical Convolute Univalves._ + +The Nautilus, the Spirula, the Scaphite, and the Ammonite are the leading +types of this form; but when we use the term symmetrical, in reference to +these, the word must not be understood in its strictest sense, for no shell +is _perfectly_ symmetrical: but it means that there is no perceptible +difference in the proportion of the two sides; as in the human body, the +right side is larger and more powerful than the left, yet to a degree so +small that it gives no apparent bias to the figure. + +CHAMBERED SHELLS. + +Many of the shells now under consideration are chambered, that is, the +internal cavity is divided into separate compartments by plates reaching +across it, named _Septa_; and the only connection between the chambers is +formed by the small pipes passing through them, to which the name of Siphon +is attached. + +_Septa._ + +The septa are _simple_ in some species, as in the Nautilus, fig. 13. In +others they are _undulated_, having waved edges, as in some species of +Ammonites; in others they are _angulated_, as in Goniatites, fig. 480 in +the plates; and in the greater number of instances, among the Ammonites, +they are _arborescent_, or branched. + +[Illustration: 13. Section of Nautilus.--14. Undulating Septa.--15. +Arborescent Septa.] + +In the above section of a Nautilus, fig. 13, diminished in size, showing +the whorls and chambers (_c_), it will be seen that the edges of the septa +(_s_) are formed in one simple curve. In fig. 14, the upper part of an +Ammonite, the undulating line will be seen; and in fig. 15 a specimen is +given of the arborescent septa. + +_Siphon._ + +The Siphon is _dorsal_ when placed near the outside of the whorls; +_central_ when near the middle; and _ventral_ when near the inside of the +whorl, or that part which leans against the last volution. When it passes +uninterruptedly from one chamber to another, it is described as +_continuous_, as in the case of Spirula; when, on the other hand, it only +passes through the septum a little distance, and opens into the chamber, as +in Nautilus, it is _discontinuous_. + +_Whorls of Symmetrical Univalves._ + +They are _disunited_ when they do not touch each other, as in the case of +Spirula (fig. 471 in the plates); but in the contrary case they are said to +be _contiguous_. In some species of Nautilus the whorls overwrap each other +in such a manner that the early whorls are entirely covered by the last, +the edges of which reach to the centre of the disk: the spire is then said +to be _hidden_; as in the Nautilus Pompilius. In Nautilus umbilicatus the +spire is nearly hidden, the whorls not quite covering each other; but in +the greater number of the Ammonites, the largest part of the preceding +whorls is seen. To express the degree in which the whorls overwrap each +other, has caused much difficulty in concise descriptions. Perhaps it would +be well to apply the term _spiral disc_ to so much of the shell as is seen +besides the last whorl, and to describe it as large or small in diameter, +compared with the whole: or to say that the whorls of the spire are half, +or one-third, or one-fourth covered, as the case may be. + +_Aperture of Symmetrical Univalves._ + +In Ammonites Blagdeni and some others the aperture is of an oblong square; +it is then said to be _sub-quadrated_; in Nautilus triangularis it is +_angulated_; in Ammonites Greenoughi it is of an interrupted oval shape, +described as _elliptical_. In the greater number of Orthocerata, it is +rounded or _circular_. The entrance of the last whorl into the aperture of +some rounded species of Nautilus causes it to take a _semi-lunar_ form; if +rounded at the sides it is said to be reniform or kidney-shaped; if pointed +at the sides it is _semi-lunar_; and in some species of Ammonites, it is +five-sided or _quinque-lateral_. + +_Measurement of Symmetrical Conical Univalves._ + +[Illustration] + +The _width_ is measured across the aperture, which is the widest part of +the shell. The _length_ (_l_) from the dorsal part (_d_) of the aperture to +the dorsal part of the _whorl_ (_d_) on the opposite part of the shell. The +_ventral_ part of the whorls is that nearest to the axis, and the _dorsal_ +that which forms the outline of the figure. + +NON-SYMMETRICAL UNIVALVES. + +These are _conical_, _irregular_, _spiral_, or _convolute_. The _conical_ +form is when there is no enrolment of the apex. Although the Patellæ were +described as symmetrical, there are several species of Patelliform shells +which are not symmetrical. In Umbrella, for instance, the apex is oblique, +the shells being placed obliquely on the animal. In the genus _Siphonaria_, +there is a groove on one side, where the brachia or gills of the animal +rest. In the genus Ancylus, it will be observed that the apex bends on one +side, and the animal is like the Limnæa, which has a spiral shell. The cup +and saucer Limpets, or Calyptrædæ, present a group which requires to be +described, differently from the symmetrical or true Limpets. Their +structure is very curious, and they vary considerably among themselves, +some of them being simply conical, others nearly flat, or discoidal, and +others more or less spiral. But their principal peculiarity consists in +their having a small internal process or plate variously shaped, commonly +named their _septum_. + +_Septa of Limpets._ + +The septa of Limpets assume a variety of forms, the principal of which will +be seen in the accompanying engravings. + +[Illustration] + +The form from which the group derives its generic appellation is that of +the cup-shaped or _Cyathiform_ species (fig. 17). In the Crepidulæ, or +Slipper-Limpets, the septum is flat, reaching across the opening, like the +deck of a vessel; it is then described as _transverse_ (fig. 20). In +Calyptræa Equestris, it has two prominent points, and is described as +_bi-furcated_ (fig. 18). In another species, it is a three-sided plate +rather spiral at the apex (fig. 19). + +_Measurement of Cup and Saucer Limpets._ + +[Illustration] + +The line marked _a_, _p_, _ll_ indicates the direction in which the shell +is to be measured for _length_. _a_ indicates the _anterior_, _p_ the +_posterior_. The line _d_ (fig. 23), from the apex to the base, is the +_depth_. The line _b_ (fig. 28), is in the direction of the breadth. + +_Irregular non-symmetrical Univalves._ + +Serpuliform shells are irregularly twisted (_tortuous_) hollow tubes, which +were formerly considered to have been secreted by a kind of worm, but now +known to be the shells of true Molluscs, of a kind not very widely +differing from those which have regularly spiral shells. The greater part +of these are attached to foreign bodies, or to each other in groups. Some +are attached by the whole length of the shell, they are then said to be +_decumbent_. Some of these are coiled round like the Spirorbis, the little +white shell seen on the carapace of the Lobster or on leaves of sea-weeds; +they are then said to be discoidal; others again, such as the _Vermetus_, +approach more nearly to the spiral form. The deviation from the regular +spire only taking place after the few first volutions. + +SPIRAL NON-SYMMETRICAL UNIVALVES. + +As these constitute the largest class, it will be necessary to dwell upon +them in detail. First as to _measurement_. + +[Illustration] + +The length is measured from the apex, to that part of the aperture _a_ +(fig. 24), at the greatest distance from it. The _breadth_ is in the +opposite direction. The _anterior_, or front part of the aperture, is +marked _a_, where the head of the animal protrudes. + +_Spire of non-symmetrical Univalves._ + +[Illustration: Fig. 25, _obtuse_; 26, _acute_; 27, 28, _decollated_; 29, +_concave_; 30, _papillary_; 31, _mammellated_; 32, _discoidal_.] + +In counting the whorls of which the spire consists, we commence at the +apex, and reckon downwards to the last, or body whorl. The spire is +described as being long or short in relation to the aperture: in which +case, all that is above the aperture is measured with the spire. Its apex +requires particular notice, as the character of the whole shell frequently +depends upon the particulars observable in this part. It is sometimes +_obtuse_, or blunt; sometimes _acute_, or sharp. In the Cones it is +frequently flat, and in Planorbis it is concave. It is sometimes of a +different structure from the rest of the shell, retaining the horny and +transparent appearance which characterized it when the animal was first +hatched. The Tritons present an instance of this, although it is not always +observable, owing to the tenderness of the substances which causes it to +break or fall away in many specimens. A very remarkable instance also +occurs in Bulinus decollatus (cut, fig. 27, 28), so named, because the +apex, to the depth of several whorls, falls off, and the shell is +_decollated_. In this, and many more instances, among Pupæform land shells, +the occurrence of this circumstance seems to be by no means rare or +accidental, a provision having been made for filling up the opening by a +septum. A _papillary apex_ is one which is swelled at the extremity into a +little rounded nob, or nipple; and a _mammellated_ apex is one which is +rounded out more fully into the shape of a teat. + +_Whorls._ + +The spire is described as consisting of _numerous_ or _few_ whorls, and +sometimes the number of them is particularly stated. A whorl consists of +one turn of the spiral cone. The whorls are described as _flattened_, when +the sides are not bulged out so as to cause the outline of the spire to +deviate considerably from straightness: when the contrary is the case, the +whorls are said to be _ventricose_, and either _rounded_ or _angulated_. +The degree of rapidity with which the whorls become enlarged presents an +important source of distinction. The _suture_, or seam, which separates one +whorl from another is also noticed as being _distinct_ or otherwise; +_canaliculated_, or grooved; or covered by an enamel, which in some +instances is swelled into a ridge or _tumid_. + +[Illustration: Fig. 33, _few_; 34, _numerous_; 35, _rounded_, _ventricose_; +36, _angular_, _ventricose_; 37, _flattened_.] + +_Suture._ + +[Illustration: Fig. 38, _canaliculated_; 39, _enamelled_.] + +_Varices._ + +Varices are caused by periodical rests or stoppages in the growth of the +shell, when the edge of the aperture thickens, and renders the shell as +complete as when full grown. Again, after an interval, another check takes +place, and another thickened edge is formed, and so on in succession, until +the animal arrives at maturity, and the shell is full-grown. The thickened +edges successively forming the aperture, remain visible on the outside, +through all the subsequent stages. When these rests take place at frequent +periods, the varices will of course be numerous as in Harpa and Scalaria. +They occur at regular or irregular distances, varying in shape and other +characters. When the varices occur at regular intervals, and form a +connected ridge from whorl to whorl up the spire, they are said to be +_continuous_, as in Ranella; when on the contrary, the varix on one whorl +does not come in contact with that on the other, they are described as +_discontinuous_. In order to distinguish a regular varix from a mere +external ridge, it will be sufficient to notice whether its edge overlaps +the external surface, and whether it resembles the open edge of the +aperture, which true varices do. + +[Illustration: Fig. 40, _numerous_; 41, _few, continuous_; 42, _few, +discontinuous_.] + +_Aperture._ + +The aperture or opening of the spiral tube, was formerly described as the +mouth; a term calculated to convey an erroneous impression, when applied to +a part of the shell which has no correspondence with the mouth of the +animal. The word _aperture_ is used by modern writers in a general sense, +including the cavity, its edge, and the canals. The cavity itself is +distinguished in various shells as to its shape, which depends much upon +the degree of modification produced by the last whorl. In some cases, as in +Cyclostoma, where the aperture stands apart from the last whorl, the shape +is round, or nearly so. The Scalaria presents a good example of this. In +others, where the inner edge or lip, wrapping over the body whorl is nearly +straight, the aperture is _semi-lunar_, or half-moon shaped: this is +remarkable in the "_Neritacea_" of Lamarck, named, on that account, +"_hemi-cyclostomata_" by De Blainville. In a great number of instances, the +lower part of the body whorl enters obliquely into the upper part of the +aperture, the result being a _pyriform_, or pear-shaped opening. The +aperture is described as _long_ when it is largest in the direction of the +axis, and _wide_, in the contrary case. The _anterior_ is the part at the +greatest distance from the apex, and the body whorl; the _posterior_, the +part nearest to the apex. Thus some apertures are described as _posteriorly +contracted_ and _anteriorly widened_, or the reverse. A _linear_ aperture +is one contracted in its whole length, as in Cypræa. When the whorls are +angulated, a _trigonal_ aperture is the result, as in many species of +Trochus. Some are _transversely oval_, that is in an opposite direction to +the axis, and others _longitudinally oval_. When the whorls are formed with +two outer angles, a somewhat quadrated aperture is formed. There are other +variations too numerous to mention. + +_Apertures._ + +[Illustration: Fig. 43, Helicina, _semilunar_; 44, Pirena, _pyriform_; 45, +Cypræa, _linear_; 46, Trochus, _trigonal_; 47, Cyclostoma, _rounded_; 48, +Chilina, _posteriorly contracted_; 49, Stomatia, _transversely oval_; 50, +Murex, _longitudinally oval_.] + +The entire edge of the aperture described generally, is named the +Peritrême, but this term can only be conveniently applied in cases where, +in some at least of its characters, it is the same all round, so that one +descriptive term is applicable to the whole. As, however, this is of rare +occurrence, it is found convenient in descriptions to separate the rim from +the outer lip. In a great number of instances, this is done naturally, by a +canal, or notch at the anterior or lower extremity, and by the posterior +union of that part which overlays the body whorl with the other portion. At +these two points the outer and inner lips separate from each other: we +therefore describe the + +_Canals of the Aperture._ + +When there is neither notch nor canal, anteriorly or posteriorly, +interrupting the edge of the aperture, it is described as entire. When +there is a notch or sinus at the anterior extremity, it is said to be +_emarginated_. When the edge of this notch is expanded, and drawn out in +the form of a beak, it is said to be _canaliferous_, or to have a _canal_. +When, in addition to this, the lips are thickened and contracted +posteriorly near their junction, and drawn out so as to form a groove, it +is said to be _bi-canaliculated_, or to have two canals. The _anterior +canal_ is said to be long or short, according to the proportion which it +may bear to the rest of the shell. Thus the canal of Ranella ranina (fig. +393 in the plates), may be described as _short_; while that of Murex +haustellum, (fig. 396, pl.) is _long_. When it is wide near the aperture, +and becomes gradually contracted towards its termination, it is said to be +_tapering_, as in Pyrula (fig. 388, pl.); when the termination is sudden, +it is described as _truncated_. If, on placing the shell upon a plane, with +the aperture downwards, the canal is seen to rise upwards, it is +_recurved_. In Buccinum and Nassa it is turned suddenly over the back, and +forms a short, curved elevation; it is then described as _recurved_ and +_varicose_. If the edges meet, so as to form a tube, it is said to be +closed, as in some species of Murex and Typhis. The posterior canal is, in +some cases, _free_, or standing out from the spire, as in some species of +Ranellæ; while in others it is _decumbent_, running up the sides of the +spire, as in Rostellaria (fig. 402, pl.). + +_Canals._ + +[Illustration: Fig. 51, Fasciolaria, _truncated_; 52, Nassa, _recurved_, +_varicose_; 53, Cerithium, _recurved_; 54, Typhis, _closed_.] + +_Lips, or edges of the Aperture._ + +The part of the edge of the aperture next to the body whorl is named the +_inner_, or _columellar_ lip. Posteriorly it commences at the point of +union with the outer lip, where that touches the body whorl, the junction +being generally marked by an angle, and sometimes by a canal. Anteriorly it +terminates where there is generally seen a notch or canal, or sudden angle, +from which the outer lip proceeds. The part which setting out from the body +whorl, and proceeds outwards at a distance from the axis, till it reaches +the anterior canal or notch (or its place in case of absence) is named the +_outer lip_. In many cases the edges are united in such a manner, that it +is difficult to distinguish where the inner lip terminates, and the outer +lip commences: when this is the case, it is usual to describe the margin or +peritrême, as a whole, without distinguishing the parts. The _outer_ lip, +sometimes called the right lip, or _labrum_ of continental writers, is +sometimes acute, not being of thicker substance than the remainder of the +shell. In other cases it is _obtuse_, or thickened and rounded at the edge. +When thickened and turned backwards it is described as _reflected_; when, +on the other hand, it is turned inwards towards the axis, as in the +Cyprædæ, it is _inflected_, or involute. When it is _toothed_, a +distinction must be observed as to whether the dentations are external or +internal. If the teeth are small and numerous, it is _denticulated_; if +larger, it is _dentated_; when expanded into a kind of wing, as in some +species of Strombus and Rostellaria, it is described as _alated_; and a +family in Lamarck's system is named "Alatæ," from this very circumstance. +In some of those which are expanded, the expansion is divided into +separate, attenuated portions, they are then said to be digitated. + +_Outer Lips._ + +[Illustration: Fig. 55, Helix, _reflected_; 56, Cypræa, _involute_, +_denticulated_; 57, Sera, _alated_; 58, Murex, _digitated_; 59, +Rostellaria, _dentated_.] + +The _inner_ lip, sometimes named the _columellar_ lip, or "_labium_," is +subject to similar variations as to thickness, dentition, &c. That portion +of it which lies upon the body-whorl is frequently distinguished from that +which intervenes between it and the notch or canal. De Blainville, +restricting the term _lip_ "bord gauche" to the former portion, applies the +term "columella" to the latter; and in some instances this may be the more +convenient method of describing the part in question. The columellar lip is +sometimes _detached_ entirely from the body of the shell, as in Murex +haustellum; in others it is _decumbent_, or lying over the last whorl, +although quite distinct, and in some cases, _thickened_, _callous_, or +_tumid_. + +At the lower or anterior part, sometimes called the _columella_, there are +in many instances flattened, laminated folds; these are particularly +conspicuous in the genera Cymba and Melo, where, being obliquely spiral and +laminar, they are extremely elegant, presenting to the eye graduated +repetitions of the line of beauty. In other cases, as in the Turbinellæ, +they are more horizontal and thickened. + +In some cases the columella is swelled into a varicose mass; as in Oliva, +Ancillaria, &c.; it is then described as _tumid_ or varicose. It is +sometimes _tortuous_, and sometimes straight, and is susceptible of many +variations, too minute and particular to be described in this part of the +work. + +COLUMELLAR LIPS. + +[Illustration: Fig. 60, Melo, _obliquely plaited_; 61, Turbinellus, +_horizontally plaited_; 62, Ancillaria, _varicose_, _tortuous_; 63, Natica, +_straight_.] + +OPERCULUM. + +The aperture of many species of shells remains constantly open; but in a +great number of species it is occasionally closed, whenever the animal is +retracted within the shell, by a calcareous or horny piece called the +operculum. This must be distinguished in the first instance from another +kind of calcareous covering, which in some univalve shells serves to close +the aperture during a certain portion of the year. This piece, named the +_epiphragm_, although hardened and shelly in appearance, is no real part of +the animal or of the shell; being only a secretion temporarily hardened, +for the purpose of defending the animal from external influences during the +_hibernating_ or _torpid_ season, to be dissolved when that season is at an +end. On examining this piece, it will be observed that it is not formed in +regular layers like the rest of the shell; while the true operculum is of a +regularly laminated structure, having a nucleus and receiving obliquely +deposited additions, either in a lateral spiral or concentric direction. It +is attached to the posterior part of the foot on the upper surface; and +when the animal retires within its shell, that part of the foot enters +last, drawing the operculum after it, and thus closing the aperture. + +The opercula of various shells differ in the first place as to their +chemical composition. They are _calcareous_ when formed principally of +calcareous matter, like the rest of the shell, as in Neritina, Nerita, and +some others. They are _corneo-calcareous_, when upon an internal lamina of +horny consistency there is a thickened layer of shelly matter. This is the +case with shells of the genus Turbo and Phasianella, which are on this +account distinguished from those of the genus Trochus; the opercula of the +latter being horny or _corneus_. + +The size of the operculum is distinguished by comparison with the rest of +the shell; thus, those of Strombus, Cassis, &c. are small; while those of +Cyclostoma and others are large, filling up the cavity at its outer edge. + +The direction in which the successive layers are deposited, forms another +ground of distinction. The disc is formed in some instances of a series of +whorls, the apex or nucleus being more or less central; if these whorls are +numerous, the operculum is described as _multispiral_, as in shells of the +genus Trochus; if few, as in Cyclostoma, it is _paucispiral_. In some +instances the flattened spire consists of but one whorl, it is then +_unispiral_; and when scarcely one turn is completed, it is described as +_subspiral_. When the layers are applied upon each other in such a manner +that the nucleus is central, and the edges of the subsequent layers are +extended beyond each other all around, so as to form rims, the operculum is +described as _concentric_; if the nucleus is lateral, or at one side +without being spiral, it is _lammellated_; and when it forms a terminal +point, enlarging in the form of a finger-nail or claw, it is +_unguiculated_. In the operculum of a Neritina, there is a lateral process, +by means of which it is locked into the columella, the term _articulated_ +is then applied. In that of Navicella, there is also a process which +appears to radiate from the nucleus, it has therefore been described as a +_radiated_ operculum. + +_Opercula of Spiral Univalves._ + +[Illustration: Fig. 64, _multispiral_; 65, _paucispiral_; 66, _concentric_; +67, _articulated_; 68, _radiated_; 69, _lammellated_; 70, _unguiculated_.] + +BIVALVE SHELLS. + +Bivalve shells, named Conchacea by Lamarck, are those which consist of two +principal portions united to and folded upon each other by means of a +hinge. The pieces united compose the shell, while each piece separately is +called a valve. Considering the bivalve shell as a whole, it will be +necessary, in the first instance, to describe the position in which it is +to be observed, in order to give the student a clearly defined notion of +what is intended, when terms expressive of height, depth, length, breadth, +&c. are used, as well as when the anterior and posterior extremities are +spoken of. For this purpose, we must suppose the animal to be living and +creeping along the bed of the sea by means of its foot; where this foot +protrudes, will be the _ventral margin_, and the opposite part the _dorsal +margin_ of the shell. There will then be a valve on each side; and if we +further suppose the animal to be walking forward with its back to the +observer, the _right_ and _left_ valves will correspond with his right and +left sides. + +_Measurements._ + +[Illustration] + +The _length_ will be measured from _anterior_ (_a_) to _posterior_ (_p_), +and the lines of growth running in the same direction will consequently be +_longitudinal_ or _concentric_; _transverse_ of some authors. The height +will be from the umbones (_u_), to the _ventral margin_, and lines or bands +in that direction are termed _radiating_; longitudinal, according to some +authors. + +The points from which the growth of the shell commences, are called the +_umbones_; these usually turn towards the anterior part of the shell: if +this circumstance fails to point out the anterior, it may in many cases be +distinguished by the muscular impressions of the mantle. If this has a +sinus or winding, it is always near the posterior muscular impression; and +in all cases where there is an external ligament, it is on the posterior +side. + +There is sometimes an impression near the front of the umbones, which forms +a semicircle on each valve; the space within this semicircle is called the +_lunule_ (wood-cut, fig. 71 and 72, _l. l. l._); a corresponding +depression, when it exists on the posterior margin near the umbones, is +named the escutcheon. + +_Hinge._ + +[Illustration: Fig. 73, _l t_, lateral teeth; _c t_, cardinal teeth; _c_, +cartilage under the ligament; _l_, ligament; _f_, fulcrum of the ligament.] + +The _hinge_ of the shell is on the _dorsal_ margin, and is composed of the +various apparatus by which the two valves act upon each other in opening +and shutting. It consists of a _ligament_, which is placed on the dorsal +margin, just at the back of the umbones, and unites the two valves +together; the _cartilage_ or thick gristly elastic substance, sometimes +found close to the _ligament_, to which it then forms an inner coating, and +sometimes received into a pit within the shell. It serves the purpose of +keeping the shell open when not forcibly closed by the adductor muscles. An +inner layer of shelly matter upon which are placed teeth, and pits to +receive them on the two valves reciprocally. Each of these it will be +necessary to treat of more at large; observing, at the same time, that in +some species of Bivalves these parts may be wholly or partially wanting. +Thus we meet with some shells, such as the Muscle, without teeth; and there +is the group containing Pholas, &c. the hinge of which is destitute of +teeth and ligament, the two valves being kept together by loose cartilages, +and by the contracted space in which they are confined. + +_Ligament and Ligamentary Cartilage of the Hinge._ + +These two distinct substances have been described by many writers as +though, composing the same mass, they were of one substance; but the +difference may very easily be explained. The _true ligament_ is external, +being fixed on the edge of one valve behind the umbones, and passing over +in an arch to the corresponding edge of the other, very correctly retaining +the name of _ligament_, because it serves the purpose of binding the two +together. The thick, elastic substance, which Mr. Gray names the +_cartilage_, is sometimes found in connexion with the ligament, so as to +form one mass with it, although it is always separable and placed within +it: it is sometimes placed quite within the shell, and separated from the +ligament, in a pit or hollow formed for its reception in the hinge lamina, +near the centre. It is found in both valves, and being elastic, the portion +in one valve presses against that in the other, so as to keep the valves +apart, unless voluntarily closed by the adductor muscles of the animal. The +ligament is sometimes spread over an external area, as in Arca, while the +cartilage is placed in several grooves of the same area, beneath the outer +covering. + +_Hinge lamina, Teeth and Fulcrum of the Ligament._ + +In a great variety of cases, there is a thickening of the substance of the +shell within, under the dorsal margin; this is named the hinge lamina. It +is sometimes merely callous; but in many cases it has raised _teeth_ in +both valves, those in one valve entering into corresponding cavities in the +other. Those which are placed immediately below the umbones, and seem to +take their rise from beneath them, are called _cardinal teeth_; those at a +distance from the umbones, which are seen to lie along the upper margin of +the shell are named _lateral teeth_. + +When the cardinal teeth terminate in a double point, which is not +unfrequently the case, they are said to be _bifid_. The lateral teeth, in +various species, are distinguished as terminating _near_ to, or at a +_distance_ from the umbones. In the Nuculæ and Arcæ there is a row of teeth +placed across the hinge lamina. In which case, the lateral cannot be +distinguished from the cardinal teeth. + +_Muscular Impression._ + +[Illustration: Fig. 74. _a, anterior; p, posterior; m i, muscular +impressions._] + +Lamarck divides the Bivalve shells into two general orders; the first is +named "Dimyaria," having two adductor muscles; and the second, +"Monomyaria," having but one. These adductor muscles are used for the +purpose of drawing the valves together, being composed of contractile +fibrous gristle, fastened firmly to the inner surface of each valve. The +place where they are thus fixed may be seen when the animal is removed, by +depressed areas, which are generally pretty well defined, and are named +_muscular impressions_. Where there is but one adductor muscle, there will +be but one of these impressions near the centre of each valve, but in the +Dimyaria, where there are two, the impressions are seen, one on the +anterior, and one on the posterior of each valve, just below the _hinge_ +lamina. They are sometimes _complex_, that is composed of several portions +in a group; but in general, they are simple and well defined. + +They are also described as large or small, in proportion to the size of the +shell; regular or irregular in form. The animal is attached to the inner +surface by the fibrous portions of the mantle, which creates a linear +impression or _cicatrix_, commonly described as the _palleal impression_, +or muscular impression of the mantle. It runs near the ventral margin from +one muscular impression to the other, sometimes in a smooth _continuous_ +line or band, and sometimes in an interrupted series of small impressions. +Near the point of union with the posterior muscular impression, there is +sometimes a more or less considerable winding inwards towards the centre of +the shell, and back again towards the point of union. This is named the +_sinus_, and is distinguished as being _angular_ or _rounded_, large or +small, according to the species. When it enters towards the centre of the +shell in a tongue-shaped outline it is said to be _ligulate_. Where it +exists it affords a certain index to the posterior side of the shell; as it +is the region through which the excretory tubes pass. + +_Umbones._ + +These are the prominent points of the dorsal edge, where the growth of the +shell commenced, and are called beaks, by some English writers. In some +instances they are close to each other; in others they are rendered distant +from each other by the intervention of areas in the hinge, as in Spondyli, +&c. In Pectunculus they are _straight_; in Venus _curved_ towards the +anterior margin; in Isocardia, _spiral_; in Chama, _decumbent_; in Diceras, +_free_. In shells subject to external corrosion, the process commences at +the umbones. + +[Illustration: Fig. 75, _distant_; 76, _straight_; 77, _curved_; 78, +_spiral_; 79, _decumbent_; 80, _free_; 81, _close_.] + +GENERAL CHARACTER OF BIVALVES. + +When the _breadth_ is spoken of, the distance between the most convex parts +of both valves, when closed, is intended; but when an expression implying +_thickness_ is used, it refers to the substance of each valve: it is +important to bear this in mind, as many persons have been misled by +descriptions in which the distinction has not been attended to. Glycimeris +(fig. 67 in the plates) is a _thick_ shell, but Anatina (fig. 69 in the +plates) is a _broad_ one. + +_Regularity._ + +A great number of Bivalves are extremely regular in their form. These are +generally locomotive, and consequently free from those obstructions in +growth occurring to stationary shells, which being confined in a particular +position, or to a particular spot, modify their shape according to the +substance with which they come in contact, and thus become irregular. This +is generally the case with shells which are attached to submarine +substances, such as Spondyli, Oysters, &c.; and the degree of irregularity +will depend upon the extent of surface involved in the attachment. In the +case of fixed shells, the attached valve is usually termed the under valve, +and the other which moves freely upon the hinge, is termed the upper valve. + +_Form and Proportions._ + +Bivalves are said to be _equivalve_ when the two valves correspond in +extent, breadth, and thickness; and of course _inequivalve_ in the contrary +case. They are _equilateral_ when a line drawn from the umbones to the +ventral margin would divide the shell into two nearly equal parts; and of +course _inequilateral_ in the opposite case, which occurs in the great +majority of instances. + +A Bivalve is said to be _compressed_, when the distance is small from the +most prominent part of one valve to that of the other. It is _cylindrical_ +when lengthened, and more or less rounded in its breadth, as in Lithodomus +(fig. 161 in the plates). It is _cordiform_ when the shape presents a +resemblance to an imaginary heart, as in Cardium cardissa (fig. 122 in the +plates), and in the Isocardia (fig. 126 in the plates). It is _linguiform_ +when it resembles a tongue in shape, as in Vulsella (fig. 185 in the +plates); _rostrated_ when it protrudes at either extremity, and terminates +in a kind of point, as in Sanguinolaria Diphos (fig. 99 in the plates); +_truncated_ when it ends in a square or angle, as if cut off; an example of +which may be seen in Solen (fig. 60 in the plates). + +Other Bivalves are distinguished as being _auriculated_, having processes +flattened and expanded on either side of the umbones, as in Pecten (cut, +fig. 82). When there is one of these on each side of the umbones, it is +_bi-auriculated_; when only on one side, it is _uni-auriculated_. When the +expansion is very broad, as in Unio alatus (fig. 142 in the plates), and in +the Hammer Oyster (cut, fig. 83), the term _alated_ is used. + +[Illustration: Fig. 82, _auriculated_; 83, _auriculated_, _alated_.] + +With regard to these alated species of _Uniones_, it is necessary to +observe that they are also "_adnate_," as it is termed; the two valves +being joined to each other by the dorsal edge of the expanded parts, and +united so completely in substance with each other, that they cannot be +separated without being broken. Many other terms are used to express +difference in Bivalves, but being generally applicable to Univalves and +Multivalves, as well as to them, they will be found explained at large in +the alphabetical part of the work. + +MULTIVALVE SHELLS. + +These are of three different kinds; first, the "_dorsal_," as they are +termed by Linnæus, because they form a ridge in the back of the animal. +They are composed of eight pieces, or separate valves, placed in a +longitudinal series, being joined to each other by inserted lamina, and +named _Articulata_ by De Blainville, on that account. The genus Chiton is +the only example of this kind of Multivalves. + +[Illustration: Fig. 84, 85, Chiton. _a_, anterior; _p_, posterior; _d_, +dorsal ridge; _l l_, lateral areas of the valves; _c c_, central areas; _i +i_, inserted lamina; _m_, margin.] + +The second kind, M. De Blainville terms the _lateral_ bivalves, the pieces +being placed in pairs on each side of the animal; these compose the +"Pedunculated Cirripedes." + +[Illustration: Fig. 86, Anatina.] + +They differ considerably in the number and arrangement of the valves; the +small ones, which are found near the peduncle in some species, are +sometimes termed accessary valves; those which form the edge through which +the bunch of Cilia protrude, are termed _ventral_, and those on the +opposite side _dorsal_. The extremity joining the peduncle is the basal, or +anterior; and the upper extremity is the apsiral, or posterior. The +peduncle is the medium of attachment to submarine substances, to which this +well known tribe of shells adhere. + +The third kind are termed _coronular_ by De Blainville, and compose the +order Sessile Cirripedes of Lamarck; they consist of a number of valves +placed against each other side by side in a circle, supported on a plate, +or tube, or cup, and closed by an operculum composed of two or more valves. + +The _basal support_ is sometimes thick and flat, sometimes forming an +elongated tube, and sometimes hollowed out into a cup. In other species it +is altogether wanting. The operculum always consists of more than one +piece, generally of two pairs: they are either articulated to each other by +serrated edges, and placed against each other conically, as in Balanus, or +they lie flat in two pairs against each other. Through the ventral pair the +_cirrhi_ protrude. + +The _parietal_ valves, composing the principal part of the shell, vary in +number, form and position. The _anterior_ valves are placed on the same +side with the cirrhi; the _posterior_, those on the opposite side; and +those which remain between on each side are the lateral valves. In many +cases, particularly in Balanus, each valve is separated into the +_prominent_ and _depressed_ areas, and the inserted lamina. In some +instances, the parietal portion is formed by a single rounded piece. + +[Illustration] + +In the accompanying cut (87), the prominent areas are distinguished by the +letters _pr_, and the depressed areas by _r_; the posterior valves of the +operculum are marked _p. o._, and the anterior _a. o._ The basal valve +(fig. 88) belongs to a Balanus. Fig. 89 is an Acasta, the cup-shaped base +of which is represented at fig. 90. + +In the foregoing explanations we have omitted many of those general terms +which, relating to external characters, are applicable to shells in almost +every division of the system. It may be as well, however, to enumerate a +few of them in this place, although they are explained under their +respective letters in the alphabetical part of the work. + +When bars or ribs, or large striæ are crossed by others radiating from the +umbones, shells are said to be _cancellated_, as represented in cut, fig. +91. When there is a series of nodules or spines on the upper part of the +whorls, they are _coronated_, as shewn in cut, fig. 92. When a series of +projecting parts overlay each other, in the manner of tiles, as in the cut, +fig. 93, the word _imbricated_ is applied. When marked by a regular series +of ridges, radiating from the apex, they are _pectinated_; the species of +Chiton, a single valve of which is represented in cut, fig. 94, has +received the specific name of _pectinatus_, in consequence of this +character. Shells are said to be _plicated_ when characterized by angular +bendings or foldings in their surface, as shewn in cut, fig. 95. A strong +instance of this is seen in the Ostræa Crista-Galli. When the margin of any +shell has a series of minute notches, resembling the teeth of a saw, it is +said to be _serrated_; when covered with raised points or spines it is +_aculeated_; and when striated in both directions, it is _decussated_; when +covered with a number of raised rounded points, it is _granulated_; and +having a series of these points placed in a row, near or upon the edge, it +is _denticulated_, as already explained in reference to the outer lips of +Spiral Univalves. When the external surface is rendered uneven by raised +knobs, it is said to be _tuberculated_; and if rendered rough and prickly +by sharp points it is _muricated_, as in the cut, fig. 97. The term +_reticulated_ is applied to fine raised lines, crossing each other, and +resembling fine net-work. + +[Illustration: External surface. Fig. 91, _cancellated_; 92, _coronated_; +93, _imbricated_; 94, _pectinated_; 95, _plicated_; 96, _decussated_; 97, +_muricated_; 98, _foliated_.] + +By the foregoing general observations and explanations, it is trusted that +the reader will be prepared for the following exposition of the general +arrangement of Lamarck, and the principles upon which it is founded. + + * * * * * + +GENERAL ARRANGEMENT + +ACCORDING TO LAMARCK. + +In Lamarck's "Histoire Naturelle des Animaux sans Vertebres," he divides +the invertebrata into classes, the 9th, 10th, and 11th of which include +animals possessed of shells properly so called. These are the ANNELIDES, +the CIRRIPEDES, the CONCHIFERA, and the MOLLUSCA. + +The class ANNELIDES constitutes the 9th, and is divided into three orders, +namely, the "Apodes," "Antennees," and "Sedentaires"; the last of which, +_Sedentaria_, alone contains testaceous animals. This order includes +tubular shells, which, with the exception of Dentalium, are irregularly +twisted, and attached to each other, or to extraneous substances. The first +family _Dorsalia_, contains the genus Siliquaria (plates, fig. 1), known +from the Serpulæ, by the slit which passes through the whole length of the +shell on the upper surface of the tube. The second family, _Maldania_, has +the genus Dentalium (plates, fig. 2), a species of which are commonly known +by the name of "tooth shells"; these are regularly formed, curved conical +tubes, open at both extremities. The third family, _Serpulacea_, includes +the genera Serpula, Spirorbis, Galeolaria, Vermilia, Spiroglyphus, and +Magilus. The only shell that a learner would be likely to place among these +incorrectly, according to the system, is the Vermetus (plates, fig. 345), +which being regularly spiral at the apicial extremity, has been placed +among the Mollusca; to which situation the whole of the shells under +consideration have a better title than is generally supposed. It should be +mentioned that the Serpulacea are provided with opercula. + +Class CIRRIPEDES. + +This class constitutes the tenth of invertebrated animals, and receives its +name from the jointed and ciliated branchia which protrude between the +opercular valves. They are Multivalve shells, and were all included in the +single genus Lepas in the system of Linnæus, and are commonly known by the +name "Barnacles." Lamarck has, however, divided them into two distinct +orders. First, the _Sessile_ Cirripedes or those which being composed of +several valves, joined to each other, side by side in a circle, are +attached to each other, or to submarine bodies by the basal portion of +their own substance, and form a hollow, irregular cone, with the aperture +above closed by an operculum consisting of two or more valves. Secondly, +the _Pedunculated Cirripedes_, which are composed of valves placed in pairs +against each other, so as to form a flattened disc attached by means of a +tendinous tube called a peduncle. The first of these orders includes the +genera Tubicinella, Coronula, Platylepas, Clitia, Conia, Elmineus, +Catophragmus, Octomeris, Balanus, Creusia, Nobia, Savignium, Pyrgoma, Adna, +Megatréma. The second contains the genera Pentelasmis, Scalpellum, Smilium, +Pollicipes, Bisnæus, Lithotrya, Ibla, Octolasmis, Cineras, Otion. + +Conchological writers are not agreed as to the propriety of allowing the +above to enter into the present science. + +Class CONCHIFERA. + +The shell of a conchiferous animal is always bivalve, composed of two +pieces placed opposite to each other, joined at the dorsal margins by an +elastic hinge. All true bivalve shells belong to animals of this class; and +the correspondence between the shell and the animal is so true that on +examining an empty bivalve shell we can not only determine that its +inhabitant belonged to this class, but also decide on the particular order +and family in which it should be placed, without seeing the soft parts. + +The first general division of Conchifera is that which results from +observing the muscular impressions, or marks made on the inner surface of +the valve by the insertion of the adductor muscles. All Conchifera are +divided into two orders, as follows: + +First Order, _Conchifera Dimyaria_. + +Having two adductor muscles, and consequently two impressions in each +valve. They are separated into the following families: + + 1. _Tubicolæ_ (plates, fig. 44 to 54), having shelly tubes besides the + valves. This family contains the genera Aspergillum, Clavagella, + Teredina, Teredo, Xylophaga, Fistulana, and Gastrochæna. + + 2. _Pholadaria_ (plates, fig. 55 to 59), cylindrical, living in holes + in rocks pierced by the animals. Lamarck places in this family the + genera Pholas and Gastrochæna, the last of which belongs more properly + to the family Tubicolæ, as placed above. + + 3. _Solenacea_ (plates, fig. 60 to 68), longitudinally (transversely, + Lam.) elongated, open at the anterior and posterior extremities. This + family contains the genera Solen, Pholadomya, Panopæa, Glycimeris + (Solecurtus) and Solenimya. + + 4. _Myaria_ (plates, fig. 69 to 76), ligament internal. A spoon-shaped + ligamentary pit in one or both valves. Shell generally gaping at one or + both extremities. This family includes the genera Anatina, Mya, + Anatinella, Lyonsia, Myochama, Cleidotherus. + + 5. _Mactracea_ (plates, fig. 77 to 88), the cartilage placed in a + trigonal pit, with a small external ligament. The genera Lutraria, + Mactra, Crassatella, Erycina, Ungulina, Amphidesma, and Solenimya + belong to this family, the last of which ought to have been placed + among the Solenacea, as above. + + 6. _Corbulacea_ (plates, fig. 89, 90), inequivalve, with an internal + ligament resembling the Mactracea, but differing in having one valve + deeper than the other, although regular shells. This small family + contains only the genera Corbula and Pandora. + + 7. _Lithophagidæ_ (plates, fig. 91 to 97), irregular, terebrating, + living in holes of rocks. The genera are Saxicava, Petricola, and + Venerirupis. + + 8. _Nymphacea_ (plates, fig. 98 to 110), ligament external, generally + placed upon a prominent fulcrum, which passes from the inside to the + outside of the hinge; valves generally gaping at the extremities. This + family contains the genera Sanguinolaria, Psammobia, Psammotæa, + Tellinides, Corbis, Lucina, Donax, Capsa, and Crassina. + + 9. _Conchacea_ (plates, fig. 111 to 121), regular, having several + cardinal teeth and sometimes lateral teeth. The Conchacea constitute + one of the most beautiful and numerous families of the class; they + present equivalve shells, which are always regular, unattached, and in + general closed, especially at the sides; they are always more or less + inequilateral. They are divided into the _fluviatile_ and _marine + Conchacea_, the first containing the genera Cyclas, Cyrena, and + Galathæa, found in rivers; and the second, Cyprina, Cytherea, Venus, + and Venericardia. + + 10. _Cardiacea_ (plates, fig. 122 to 130). This family, which resembles + the last in some general characters, are also regular and equivalve, + and are generally provided with radiating ribs, which are seldom seen + in the Conchacea. The genera enumerated in this family are Cardium, + Cardita, Cypricardia, Hiatella, and Isocardia. + + 11. _Arcacea_ (plates, fig. 131 to 138). These are known by having a + row of numerous small teeth on the cardinal hinge in each valve. The + genera included are, Cucullæa, Arca, Pectunculus, Nucula. + + 12. _Trigonacea_ (plates, fig. 139 and 140). It is doubtful whether + this family should remain distinct. As of the two genera placed in it, + the first, Trigonia, is thought by some naturalists to have strong + affinities with Nucula, in the family of Arcacea; and the latter, + Castalia, certainly belongs to the Nayades. + + 13. _Nayades_ (plates, fig. 141 to 152). These are fresh-water shells, + covered on the outside by a thick horny epidermis, and pearly within. + They include the genera Unio, Hyria, Anodon, Iridina. + + 14. _Chamacea_ (plates, fig. 153 to 155), inequivalve, irregular, + foliaceous, attached; containing the genera Diceras, Chama, and + Etheria. + +Second Order, _Conchifera Monomyaria_. + +Having one adductor muscle, and therefore only one impression in each +valve. They are separated into the following families:-- + + 1. _Tridacnacea_ (plates, fig. 156 & 157), transverse, equivalve, with + an elongated muscular impression, near the centre of the ventral + margin; margin undulated at the termination of the radiated large ribs. + The genera Tridacna and Hippopus are included. + + 2. _Mytilacea_ (plates, fig. 158 to 162), generally regular, with the + hinge linear, without teeth, occupying the greater part of the dorsal + margin. This family includes the genera Modiola, Mytilus, Pinna. + + 3. _Malleacea_ (plates, fig. 163 to 170), shell generally thin, + inequivalve, irregular, foliaceous, with the hinge linear. This family + contains the genera Crenatula, Perna, Malleus, Avicula, Meleagrina. + + 4. _Pectinides_ (plates, fig. 171 to 178). The Pectinides are generally + regular or nearly so, with the shell solid; the greater part of them + are auriculated at the dorsal margin, and generally characterized by + ribs radiating from the umbones. The genera are Pedum, Lima, + Plagiostoma, Pecten, Plicatula, Spondylus, Podopsis. + + 5. _Ostracea_ (plates, fig. 180 to 192). The shells of this family are + irregular, generally attached and foliaceous. They compose the genera + Gryphæa, Ostræa, Vulsella, Placuna, Anomia. + + 6. _Rudistes_ (plates 193 to 200). This family is composed of a + particular association of shells, which appear on one side to be + connected with the Ostracea; and on the other to approach the + Brachiopoda. They differ from Ostracea in having no hinge or ligament, + and only resemble them in their irregularity and foliaceous structure. + The following six genera are placed by Lamarck in this + family:--Sphærulites, Radiolites, Calceola, Birostrites, Discina, + Crania. Of these, Calceola, Discina, and Crania are shewn to belong to + the Brachiopoda. + + 7. _Brachiopoda_ (plates, fig. 201 to 219). The shells of this family + are inequivalve, equilateral, and attached to marine bodies by a tendon + passing through one of the valves. The animals have, near their mouth, + two elongated, ciliated arms, which are spirally rolled when at rest. + The following genera are enumerated by Lamarck, Orbicula, Terebratula, + Lingula. + +MOLLUSCA. + +Lamarck applies, or rather restricts, this name to those invertebrated +animals, which while they are inarticulate in all their parts, have the +head sufficiently advanced at the anterior part of the body to be +distinguished; which is not the case with the Conchifera. All the shells +are univalve, and are divided into six orders, namely, the PTEROPODA, which +have wing-shaped natatory organs or fins, and have _light_, _thin +transparent_, _nearly symmetrical_ shells; the GASTEROPODA, with the foot +not distinguishable from the rest of the body, have _patelliform_, _open_, +and _scarcely spiral_ shells; the TRACHELIPODA with the foot distinct and +attached to the neck of the animal, have _spiral_, _non-symmetrical_ +shells. The CEPHALOPODA, with arms covered by suckers surrounding the head +of the animal, have generally _symmetrical convolute_ shells. The +Cephalopoda are divided into _C. polythalamia_, which have the internal +cavity divided into chambers by septa, as in the Nautilus; and the _C. +Monothalamia_, which are not so divided, as the Argonauta. The order +_Heteropoda_ contains the genus Carinaria alone. + +Order _Pteropoda_. + +This order, containing hyaline, symmetrical, non-spiral shells, as above +described, is not divided into families, but contains the following genera, +Hyalæa, Cleodora, Limacina, Cymbulia; the first of which, although composed +of a single piece, resembles a bivalve so nearly, that Linnæus actually +placed it in his genus Anomia. + +Order _Gasteropoda_. + +With the exception of the genus Bulla and Vitrina, the last of which forms +a passage into the next order, the shells contained in this order are +_patelliform_, _open_, _and scarcely spiral_. They are divided into the +following families:-- + + 1. _Phyllidiana_ (plates, fig. 227 to 231), containing the genera + Chiton, Chitonellus, and Patella, the two former of which present the + only exception to the statement above made, that all the shells of + Mollusca were univalve. + + 2. _Semiphyllidiana_ (plates, fig. 232 and 233). Of the two genera + contained in this family, Pleurobranchus is broad, thin, and slightly + spiral at the apex, and Umbrella is flat, circular, with a central + apex. + + 3. _Calyptracea_ (plates, fig. 234 to 246). The patelliform shells of + this family, although united by no other general characters, are + brought together by the characters of the animals which produce them. + The genera are Parmophorus, Emarginula, Siphonaria, Fissurella, + Pileopsis, Calyptræa, Crepidula, Ancylus. + + 4. _Bulleana_ (plates, fig. 247 to 253), contains the genera Bulla and + Bullæa. + + 5. _Aplysiacea_ (plates, fig. 254 and 255). The genera Aplysia and + Dolabella are both expanded, somewhat flattened shells, with the apex + placed at one extremity, and slightly spiral. + + 6. _Limacinea_ (fig. 256 to 263). Many of the animals (slugs) are + without shells; some, as the Limax, or common garden slug, have a + slightly developed calcareous piece, hidden beneath the mantle, and of + others the shells are scarcely spiral. The genera included in this + family are, Parmacella, Limax, Testacella, Vitrina. + +Order _Trachelipoda_. + +All the remaining spiral non-symmetrical shells are arranged in this order, +which is divided into the following families:-- + + 1. _Colimacea_ (plates, fig. 264 to 307). With the exception of the few + contained in the family of Limacina, which ought not to be separated + from this order, the whole of the land-shells are contained in this + family, and although it is difficult to notice any one character by + which terrestrial shells may be distinguished from others, few at all + conversant with the subject are liable to mistake them. There is a + general lightness and simplicity of form, which, though not clearly + definable, is generally understood. The following distribution of + genera by Lamarck, is generally acknowledged to require numerous + modifications; the genera are Helix, Carocolla, Anostoma, Helicina, + Pupa, Clausilia, Bulinus, Achatina, Succinea, Auricula, Cyclostoma. + + 2. _Lymneana_ (plates, fig. 308 to 312). The shells of this family are + found in fresh water, wells, ditches, and ponds. They are of a light + horny structure, and simple form. The genera Planorbis, Physa, and + Lymnea are placed in this family by Lamarck. + + 3. _Melaniana_ (plates, fig. 313 to 317). These are also found in fresh + water, principally in rivers; they are thicker than those of the last + family; and the greater part of them have elevated spires composed of + numerous whorls. This family contains the genera Melania, Melanopsis, + Pirena. + + 4. _Peristomata_ (plates, fig. 318 to 322). These are also fresh-water + shells, having opercula, and covered by a smooth green, or + greenish-brown epidermis. They differ from the last family in having + the peritreme entire. The genera are Valvata, Paludina, and Ampullaria. + + 5. _Neritacea_ (plates, fig. 323 to 333). The peculiarity of the shells + of this family consists in the inner lip being flattened and rather + straight at the inner edge. The genera are Navicella, Neritina, Nerita, + Natica, and Janthina, the last of which forms an exception to the + general character, and is placed by De Blainville in a family by + itself. + + 6. _Macrostomata_ (plates, fig. 334 to 341), so named, on account of + the large open aperture which they present in comparison to the spire. + The shells of this family, which contains the genera Stomatia, + Stomatella, and Haliotis, are pearly within. + + 7. _Plicacea_ (plates, fig. 342 to 344), contains the genera Tornatella + and Pyramidella. + + 8. _Scalariana_ (plates, fig. 345 to 352). The genera Vermetus, + Scalaria and Delphinula, seem to have been placed in this family by + Lamarck, on account of the whorls being distinct from each other. + + 9. _Turbinacea_ (plates, 353 to 371). The shells contained in this + family are all more or less globose, or angular, thickened and pearly + within. The following genera are included in this division by Lamarck, + Solarium, Rotella, Trochus, Monodonta, Turbo, Planaxis, Phasianella, + and Turritella. + + 10. _Canalifera_ (plates, fig. 372 to 401). The numerous genera of + which this family is formed, namely, Cerithium, Pleurotoma, Turbinella, + Cancellaria, Fasciolaria, Fusus, Pyrula, Ranella, Murex, Triton, are + distinguished by having at the anterior termination of the aperture, a + more or less elongated canal. + + 11. _Alatæ_ (plates, fig. 402 to 406). These are known by having the + outer lip more or less expanded and generally a posterior canal leaning + towards the spire. The genera are Rostellaria, Strombus, and + Pteroceras. + + 12. _Purpurifera_ (plates, fig. 407 to 429). In these, the canal, if + such it may be called, is extremely short, and turning abruptly + backwards, produces a kind of varix at the lower part of the whorl. The + genera enumerated in this family are Cassidaria, Cassis, Ricinula, + Purpura, Monoceras, Concholepas, Harpa, Dolium, Buccinum, Eburna, + Terebra. + + 13. _Columellata_ (plates, fig. 430 to 433). The shells of this family + are emarginated at the anterior extremity of the aperture, and the + inner lip is characterized by plates or folds, which, with the + exception of those on Columbella, are distinct. The genera are Mitra, + Voluta, Marginella, Volvaria, Columbella, the latter of which would be + better placed among the Purpurifera. + + 14. Convolutæ (plates, fig. 444 to 462). The well-known shells + contained in this family are distinguished for the small proportion of + the spire, if any, which remains uncovered by the last whorl. They + might be well divided into two groups, the first containing the genera + Ovulum and Cypræa, under the name of Cypræadæ, which are truly + convolute, having the spire entirely hidden; and the second containing + the genera Oliva. Ancillaria, and Conus. + +Order _Polythalamous, or Chambered Cephalopoda._ + +The greater part of the shells belonging to this order are symmetrical, and +the internal cavity is divided into separate compartments, by plates called +_Septa_. It is divided into the following families:-- + + 1. _Orthocerata_ (plates, fig. 463 to 470), containing the genera + Belemnites, Orthoceras, Nodosaria, Hippurites, and Conilites. + Hippurites certainly has no affinity with the Cephalopoda, but is + ascertained to be a bivalve shell, properly belonging to the family + Rudistes; the other genera are straight, elongated, and conical. + + 2. _Lituacea_ (plates, fig. 471), containing the genera Spirula, + Spirulina, and Lituola, the two latter of which are microscopic. + + 3. _Cristacea_, containing the microscopic genera Renulina, Orbiculina, + and Cristellaria. + + 4. _Spherulacea_, containing the microscopic genera Miliola, Gyrogona, + and Melonia. + + 5. _Radiolacea_, containing the microscopic genera Rotalites, + Lenticulina, Placentula. + + 6. _Nautilacea_ (plates, fig. 472 to 476). This family contains the + following genera--Discorbites, Siderolites, Polystomella, Vorticialis, + Nummulites, and Nautilus; the two latter of which alone are now + received in cabinets of shells, the four former belonging to that class + of microscopic fossils, now termed Foraminifera; the genus Nummulites, + although large, may probably belong to the same class, and perhaps it + would have been better to have included the remaining genus, Nautilus, + in the next family, from which it differs in having the septa which + divides the chambers simple at their edges. + + 7. _Ammonacea_ (plates, fig. 477 to 484). The edges of the septa of + these are all more or less sinuous and complicated. This family + contains the following genera, Ammonites, Ammonoceras, Baculites, and + Turrilites, the latter of which presents a singular anomaly in having + an oblique spire, like that of the order Trachelipoda, while it is + divided into chambers by sinuous septa. + +Order _Monothalamous Cephalopoda_. + +The only shells included in this order belong to the genera Argonauta +(plates, fig. 485), placed here by Lamarck, and Bellerophon (plates, fig. +486 and 487), a fossil genus subsequently added. + +Order _Heteropoda_. + +The singular and beautiful transparent shell contained in this order, under +the generic name Carinaria, forms a covering to a small portion of an +animal, equally remarkable and equally distinct from those of all other +orders. + + + +The above arrangement, although far from perfect, and requiring numerous +modifications, is perhaps liable to as few objections as any other yet +proposed, and will certainly be more easily understood by those who have +not the opportunity of studying the soft parts of the animal. + + * * * * * + +CONCHOLOGICAL MANUAL. + + ABIDA. Leach. A genus founded on a species of PUPA, which has the + peristome slightly reflected, and numerous plaits in the aperture. Pupa + Juniperi, Pupa secale, Draparnaud. Great Britain; also Central and + Southern Europe. + + ABRA. Leach. A genus composed of AMPHIDESMA tenue, prismaticum, and + other small thin species. British Channel and Mediterranean. _Fam._ + Mactracea. + + ABSIA. Leach. LITHOTRYA, Sowerby. _Fam._ Pedunculated Cirripedes. + + ACAMAS. Montfort. BELEMNITES multiforatus, Blainville. A species + described as being perforated at the apex, by a stellated perforation. + No species of Belemnite at present known agreeing with the description; + it is supposed to have been taken from a broken specimen. + + ACANTHOCHETES. A name given to a species of Chiton having bunches of + bristles at the sides of the valves. + + ACARDO. Commerçon. Described from a pair of bony plates, taken from the + vertebræ of the Whale, and mistaken for a bivalve shell, destitute of a + hinge. + + ACARDO. Swainson. A generic term applied by Swainson to the nearly + toothless species of Cardium, named C. edentulum by some authors; C. + Greenlandicum by others: fig. 123*. + + ACASTA. Leach. _Order_, Sessile Cirripedes, _Lamarck_. BALANUS + _Montagui_, Sowerby. A small genus separated from Balanus, on account + of the cup-shaped base, but re-united by Sowerby, who shews, in his + Genera of Shells, that this is a merely accidental circumstance, + resulting from the situations in which the shells acquire their growth. + If, for instance, the Balanus be attached to a flat surface, in an open + situation, the base will be short and flat; if it be placed in a hollow + among other growing substances, it will be lengthened out in order that + the aperture of the shell may be even with the outer surface of the + surrounding mass; and if, as in the Acastæ, it be imbedded in a soft + and loose substance, the base, being left to itself, will take a + regular form. The Acastæ are found imbedded in sponges. _Ex._ Balanus + Montagui, of Great Britain, fig. 26. Also found in the Pacific ocean + and Philippines. + + ACAVUS. Montfort. _Fam._ Limacinea, Blainville; Colimacea, Lamarck. A + division of the genus Helix, which may be considered synonymous with De + Ferrusac's sub-genus Helicogena. De Montfort has given H. Hæmastoma, as + an example. Fig. 267. + + ACCESSARY VALVES, are the smaller or less important testaceous plates, + found on the hinge or dorsal margins of the true valves of some shells. + Example, the small plates on the hinge of Pholas, fig. 55, a. The + Pholades were placed by Linnæus and Bruguière among multivalve shells. + + ACEPHALOPHORA. Blainville. (_a_, without; [Greek: kephale], head.) The + third class of the type Malacozoaria, Bl. including all bivalve shells, + the animals of which have no distinct head. This class corresponds with + the Conchifera of Lamarck, and is divided into the orders + Palliobranchiata, Rudistes, Lamellibranchiata, and Heterobranchiata, + the last of which contains no genera of testaceous Mollusca. + + ACHATINA, Auctorum. _Fam._ Colimacea, Lam. (from Achates, an agate.) + _Fam._ Limacineæ, Bl. _Gen._ POLYPHEMUS, Montf.--_Descr._ Shell oval or + oblong, sub-turrited, light, thin; aperture oval, or pyriform; outer + lip sharp; columella smooth, tortuous, truncated, so as to form a notch + at its union with the outer lip.--_Obs._ It is from this notch that we + are enabled to distinguish Achatinæ from Bulini, which, moreover, + generally have a reflected outer lip. The Polyphemi of Montfort have an + undulation in the centre of the outer lip. Achatina Virginea, fig. 286. + Polyphemus Glans, fig. 288. These land shells are found in various + parts of the globe, but attain the greatest size and richness of + colouring in tropical climates; particularly in the West India Islands. + + ACHATINELLA. SOW. A small group of shells, differing from Achatina in + having the inner edge of the outer lip thickened, and a slight groove + near the suture of the spire. Fig. 287. Sandwich Islands. + + ACHELOIS. Montf. CONILITES Achelois. Knorr. Supp. T. 4, fig. 1. + + ACICULA. Nilson. ACHATINA Acicula, Auct. CIONELLA, Jeffreys. + + ACIONA. Leach. A genus described by De Blainville as consisting of + those species of Scalaria, the whorls of which do not touch each other. + If this account be correct, the genus proposed by Leach will include + the typical species of Scalaria, such as S. pretiosa. + + ACME. Hartmann. A genus formed of TURBO fuscus, Walker. AURICULA + lineata, Drap. thus described--"Shell sub-cylindrical, with a blunt + tip; mouth ovate, simple, thin, slightly reflected over the pillar, + forming a slight perforation." The animal is said to resemble a + Cyclostoma, but has no operculum. Auricula lineata, Drap. Hist. 57, t. + 3, fig. 20, 21. Southern Europe. + + ACTEON. Montf. TORNATELLA, Lam. + + ACTINOCAMAX. Stokes. A genus of Belemnitiform Fossils. + + ACULEATED. Beset with sharp spines, as the margin of Chiton aculeatus, + fig. 227. + + ACUMINATED. Terminating in a point, as the apex of Melania subulata, + fig. 313. + + ACUS. Humphrey. TEREBRA of Lamarck. + + ACUTE. Sharp, pointed, or sharp-edged. + + ADDUCTOR MUSCLE. That which draws the two valves of a shell together, + and leaves a mark on the inner surface of each, called the MUSCULAR + IMPRESSION. + + ADELOSINA. D'Orb. A genus of microscopic Foraminifera. + + ADESMACEA. Bl. (_a_, without; [Greek: Desma], _desma_, ligament.) The + 10th family of the order _Lamellibranchiata_, Bl. composed of Mollusca + which either bore tubular dwellings in rocks, wood, &c. or live in + testaceous tubes, their shells being consequently destitute of the + hinge ligament. The action of opening and shutting the valves being + limited to the narrow space to which they are confined, or else the + valves themselves being soldered into the tube, renders it unnecessary + for them to have a ligament to keep them in their places. The genera + Pholas, Teredina, Fistulana, and Septaria, belong to this family, which + corresponds in part with the families Tubicolaria and Pholadaria, of + Lamarck. + + ADNA. Leach. One of the genera separated by Leach from _Pyrgoma_, and + characterized as consisting of an upper valve, supported on a + funnel-shaped base, which is not buried in the coral to which it is + attached, like Pyrgoma, but is seen externally. The operculum consists + of four valves. Adna, fig. 32. British Channel and Mediterranean. + + ADNATE. A term applied by some authors to those shells belonging to the + family of Unionidæ, which have the valves joined together at the dorsal + margin, not like other bivalves, by a distinct ligament, but by the + substance of the shell itself, the valves appearing to grow together in + such a manner that they cannot be separated without one of them being + broken as will be seen in our figure of Dipsas plicatus, fig. 142. This + circumstance has been made the foundation of specific and even generic + distinctions, for which however it is insufficient, because many + species which when young are "_adnate_," when fully grown have their + valves joined together only by a ligament. + + ÆGLIA. Say. A division of "Unionidæ," described as having the "shell + cuneate; bosses prominent; cardinal teeth much compressed, placed on + one side of the bosses. Æglia ovata, _Say_. Occidens _Lea_. Am. Tr. + iii. pl. 10." Lardner's Encyclopedia of Malacology. + + AGANIDES. Montf. ORBULITES, Lam. + + AGATHIRSES. Montf. SILIQUARIA, Auct. + + AGINA ----? Belongs to SAXICAVA, Auct. + + AKERA. Bl. The fourth family of the order Monopleurobranchiata, Bl. + containing the genera Bulla, Bullæa and Bellerophon, which, excepting + the last, constitutes the family Bullæana, Lam. + + AKERA. A genus of extremely light, horny shells, resembling BULLA, from + which it differs, in the outer lip being separated from the body whorl, + which is elastic. _Ex._ Bulla fragilis, fig. 247. + + ALÆA. Jeffrey's. A genus of minute land shells, resembling _Vertigo_, + but separated because they are dextral, while Vertigo is sinistral. + _Ex._ fig. 292. A. marginata, Pupa marginata, Drap. found in marshy + ground, roots of trees, moss, &c. Britain and Southern and Central + Europe. + + ALASMODON. Say. A division of the genus UNIO, Auct. consisting of those + species which have cardinal, but no lateral teeth. _Ex._ A. + complanatus, fig. 141. North America and Europe. + + ALATÆ. Lam. A family of the order Trachelipoda, Lam. containing the + following genera which may be thus distinguished. + + 1. ROSTELLARIA. Sinus close to the canal; including _Hippochrenes_, + and _Aporrhais_, Fig. 402 to 404. + + 2. STROMBUS. Sinus not close to the canal. Fig. 406. + + 3. PTEROCERAS. Same, digitated. Fig. 405. + + ALATED. (From Ala, a wing.) Winged, a term applied to shells, when any + portion of them is spread out in any direction, as in fig. 403. + Hippochrenes, Montf. and fig. 147, Unio Alatus. + + ALCADIA. Gray? (B. M. Syn. p. 134) Helicinæ which have a notch in the + aperture. A distinction which it is impossible to maintain. See + HELICINA. + + ALATUS. Humphrey. STROMBUS, Auct. + + ALECTRION. Montf. BUCCINUM Papillosum, Auct. fig. 422. + + ALEPAS. Rang. A genus of Pedunculated Cirripedes without a shell. + + ALVEOLINA. D'Orbigny. A genus of microscopic Foraminifera. + + AMALTHUS. Montf. A. margaritaceus, Montf. is a species of AMMONITES + described as very flat, keeled, with an angular aperture. It belongs to + the family Ammonacea, Lam. + + AMARULA ----? A genus composed of MELANIA Amarula, Auct. and similar + species. + + AMBIGUÆ. Lam. The fourth section of the order Conchifera Dimyaria, + containing the family Chamacea, fig. 153 to 155. + + AMICULA. A genus formed for the reception of CHITON amiculatus, Auct. + the valves of which are covered by an integument; so as to be + completely hidden externally. + + AMIMONUS. Montf. CONILITES ungulatus, Knorr. A species distinguished + only by being slightly curved; _Fam._ Orthocerata, Lam. + + AMMONACEA. Bl. The fourth family of the order Polythalamia, Bl. or + chambered shells, described as thin, chambered, discoidal, convolute, + symmetrical, generally compressed, with visible whorls. This last + character is used in De Blainville's System to distinguish the + Ammonacea from the Nautilacea. This family contains the genera + Discorbites, Scaphites, Ammonites, and Simplegas. + + AMMONACEA. Lam. The seventh family of Polythalamous Cephalopoda, Lam. + containing the genera Ammonites, Orbulites, Ammonoceras, Turrilites and + Baculites, to which may be added Amalthus, Simplegas, Ellipsolites, + Nautellipsites, Hamites, Icthyosarcolites, and other genera mentioned + in the list of figures 477 to 484. + + AMMONITES. Auct. (from Jupiter Ammon.) _Fam._ Ammonacea, Lam. and + Bl.--_Descr._ Symmetrical, convolute, discoidal, orbicular; chambers + numerous, divided by lobated, branched or sinuous septa, perforated by + a Siphon; aperture generally more or less modified by the last whorl. + The fossils of the secondary strata which compose this genus are + numerous and well known; they are vulgarly termed "snake-stones," and + some of them are extremely beautiful, particularly when the internal + structure is exhibited by a section. There is some difficulty in + distinguishing them from the Fossil Nautili, for although the whorls, + being visible and the Septa _sinuous_, may be taken as the + characteristics of the Ammonites, yet there are several species which + partake the characters of both. The Orbulites of Lamarck (fig. 479) for + instance, have sinuous septa like Ammonites, but the last whorl covers + those which precede it as in Nautilus. Simplegas Montf. and Bl. (fig. + 475) has the whorls visible externally and the septa simple. Ammonites + is figured in the plates (478). + + AMMONOCERAS, or AMMONOCERATITES. Lam. (from _Ammon_ & [Greek: Keras], + ceras, horn.) The shells described under this Lamarckian genus present + an anomaly which is considered by Mr. G. B. Sowerby, sen., as merely + accidental. They resemble the Ammonites in internal structure, but + instead of being spirally convolute they are merely curved like a horn. + _Ex._ fig. 477, copied from De Blainville. + + AMNICOLA. The name of a genus mentioned in the family of Melaniana in + the conchological part of the Synopsis of the British Museum, but + unexplained. + + AMPHIBOLA ----? The same as AMPULLARIA, Auct. + + AMPHIBULIMA. Lam. SUCCINEA Patula, Auct. (fig. 266.) was first + published in the Ann. du. Mus. D'Hist. Nat. under the name Amphibulima + cucullata. The generic name was afterwards abandoned by its author, and + the species stands in his system as Succinea cucullata. West Indies. + + AMPHIDESMA. Lam. (from [Greek: Amphô], _ampho_, _ambo_, [Greek: + Desmos], _desmos_, _ligamentum_). _Fam._ Mactracea, Lam.--_Descr._ + Equivalve, oval or rounded, sub-equilateral, sometimes rather gaping at + the sides, with slight posterior fold; hinge with one or two cardinal + teeth in each valve, and two elongated lateral teeth, distinct in one + valve, nearly obsolete in the other; ligament short, separated from the + cartilage, which is elongated and couched obliquely in an excavation of + the hinge.--_Obs._ In most bivalve shells, the cartilage and ligament + are united in one mass, or placed close to each other; the contrary in + this case gives rise to the name, which signifies _double ligament_. + This circumstance distinguishes the genus Amphidesma from Tellina, + which in other respects it greatly resembles. From Lutraria it may be + known by its distinct lateral teeth, and also by its valves being + nearly close all round, while the Lutrariæ gape anteriorly. The species + do not appear to be numerous, no fossil species are known. A. + _Reticulatum_, fig. 85. West India Islands, Brazil, Coast of Pacific, + &c. + + AMPHIPEPLEA. Nilson. The type of this proposed genus is LIMNEA + glutinosa, Auct. Gray's edition of Turton, page 243, plate 9. fig. 103. + The shell is polished and the inner lip expanded. + + AMPHISTEGINA. D'Orb. A genus of microscopic Foraminifera. + + AMPLEXUS. J. Sowerby. A. _Corralloides_, fig. 463. A singularly formed + fossil, described as nearly cylindrical, divided into chambers by + numerous transverse septa, which embrace each other with reflected + margins. It occurs in the Dublin limestone, and resembles a coral or + madrepore. + + AMPLEXUS. A generic name proposed by Captain Brown for HELIX pulchella, + Drap. 112, tab. 107-134. Zurama, Leach. + + AMPULLARIA. Auct. (_Ampulla_, a rounded vessel). _Fam._ "Peristomiens," + Lam. Ellipsostomata, Bl.--_Descr._ Spiral, globular, sometimes + discoidal, frequently umbilicated, covered with a rounded, horny + epidermis; spire short; whorls rapidly enlarging; aperture elliptical, + rounded anteriorly; peristome nearly or quite entire, thickened and + slightly reflected; operculum, testaceous, annular, with a subcentral + nucleus.--_Obs._ This genus of fresh-water shells of which a few fossil + species occur, is easily distinguished from other genera, by obvious + characters, particularly by a thick, horny, greenish-brown epidermis, + and the rotundity in form. One species, the A. Cornu-arietis which + forms the type of Lamarck's genus Planorbis, requires notice on account + of its flatness, but may be known by the aperture which in the + Ampullaria is longer than wide, and in Planorbis the contrary. + Lanistes, Montf. is described from a _reversed_ species of Ampullaria. + The Ampullaria is vulgarly called the Idol Shell, and is said to be + held in great veneration by the South American Savages. The animal has + a large bag, opening beneath, placed on the side of the respiratory + cavity. It is supposed that the animal has the power of filling this + bag with water, and that it is thus enabled to live a long time out of + water. They have been brought as far as from Egypt to Paris alive, + packed in saw-dust. _Ex._ fig. 318. East and West Indies, North Africa, + South America, &c. + + AMPULLARINA ----? A genus formed for the reception of AMPULLARIA + avellana. Fig. 538. From Australia. + + AMPULLINA ----? Part of the genus HELICINA, Auct. + + ANALOGOUS. A term applied to certain species of fossil shells, which + present a certain degree of resemblance to recent species; but which + are not sufficiently similar to warrant the use of the term + 'identical,' or any other implying that they are of the same species. + + ANASTOMA or ANOSTOMA. Fischer. (from [Greek: Ana], _ana_, backwards; + [Greek: Stoma], _stoma_, mouth) _Fam._ Colimacea, Lamark. A genus of + land shells so named from the singular circumstance of the last whorl + taking a sudden turn and reflecting the aperture upwards, so as to + present it on the same plane with the spire; so that the animal walks + with the spire of the shell downwards resting on the foot. In other + respects, the two species of which this genus is composed, resemble + other Helices; and belong to De Ferrusac's division "Helicodonta." + _Tomogerus_ is De Montfort's name for this genus. _A. depressum_ is + represented in the plates figs. 271, 272. The nearest approach to this + genus will be found in the fossil shell named Strophostoma, by + Deshayes, which, however, has no teeth in the aperture and is provided + with an operculum like Cyclostoma. South America. + + ANATIFER. Brug. ANATIFA, Lam. This name, which signifies Duckbearing, + has been given to the shells commonly called Barnacles, on account of + an absurd notion entertained among the ancients, that they inclose the + young of the Barnacle duck, in an embryo state. The beautiful bunch of + jointed arms, the ciliæ of which serve the purpose of agitating the + water, so as to draw in food by the current, were supposed to be the + feathers of the future bird. For a description of these shells, see + PENTELASMIS; and fig. 34. + + ANATINA. Lam. (_That which belongs to a duck._) _Fam._ Myaria, Lam. + Pyloridea, Bl.--_Descr._ Thin, transparent, generally equivalve, + inequilateral, transverse, marine; hinge with a spoon-shaped process in + each valve, containing the cartilage.--_Obs._ Some species included in + the genus Anatina of authors, A. striata, for instance, have not the + spoon-shaped prominence, but in its place a small, testaceous, moving + appendage, connected with the interior of the hinge. These are now + separated, and form the genus LYONSIA. The genus Næara, Gray, is + composed of Anatina longirostrum, and similar species, which have + neither the bony appendage nor the spoon-shaped prominence. Mya is + distinguished from Anatina, by the thickness of the shell, and also by + having the prominence only in the hinge of one valve. Fig. 69. A. + rostrata. The Anatinæ are found in the East Indies and South Sea + Islands. + + ANATINELLA. G. B. Sowerby. (Dimunition of _Anatina_). A genus so named + from its resemblance to Anatina, from which it differs in being + destitute of the internal appendage, and having no sinus in the palleal + impression. One species having been brought from Ceylon, received the + name of Anatinella Sibbaldii. Another has lately been found in the + Philippine Islands. Fig. 70. + + ANATOMUS. Montf. Tom. 2, plate 279. A microscopic shell, appearing from + the figure to resemble SCISSURELLA. + + ANAULAX. Brogn. ANCILLARIA, Auct. + + ANCILLA. Lam. ANCILLARIA, Auct. + + ANCILLARIA. Auct. ANCILLA, Lam. (_A handmaid._) _Fam._ convolutæ, Lam. + Angyostomata, Bl.--_Descr._ Smooth, oblong, subcylindrical. Spire + short, sutures hidden by enamel. Aperture long, anteriorly emarginated + and somewhat effuse. Columella tortuous, oblique, tumid, + truncated.--_Obs._ The Ancillariæ are pretty shining shells, enveloped + almost entirely by the soft parts of the animal. They resemble Oliva, + from which they are distinguished by the suture of the spire being + filled up with shelly enamel, nearly covering the surface. The whorls + in Oliva being separated by a distinct canal. Ancillaria may be known + from Terebellum by the tumid varix at the base of the columella. The + well known Ivory shell, Eburna glabrata, _Lam._ belongs to this genus, + of which a few fossil species are found in the London clay, Calcaire + grossièr and green sand, Turin. The recent species are found in the + Islands of the Indian Ocean and Australian Seas. A. glabrata is + represented in the plates fig. 455; A. cinnamonea, fig. 456. + + ANCULOSA. Say. _Fam._ Melaniana, Lam. Ellipsostomata, Bl. A genus + proposed to include some fresh-water shells resembling those of the + genus Melania, the difference between them being that the spire of + Anculosa is more depressed, and the anterior of the outer lip more + angulated than in Melania. On an examination of the different species, + however, it will be found that this is quite unsatisfactory, as a + generic distinction; because some of the species with short flattened + spires, have rounded, and others angulated apertures. North America. An + example of each is represented, fig. 314. + + ANCYLUS. Geoffroy. _Fam._ Calyptracea, Lam. Otides, Bl.--_Descr._ Thin, + obliquely conical, patelliform; apex acute, turned sidewise and + backwards; aperture oval; margin simple.--_Obs._ Although the little + fresh-water shells described under this name, resemble those of the + genus Patella, the animals which produce them are nearly allied to the + Lymneanæ. And, it may also be observed, that the shells themselves + differ from Patella in not being quite symmetrical, having the apex + turned on one side. A. fluviatilis, fig. 246. Found in Great Britain, + and in Southern and Central Europe, West Indies, &c. + + ANDROMEDES. Montf. VORTICIALIS, Lam. _Fam._ Nautilacea, Lam. A genus of + microscopic Foraminifera. + + ANGULATED. (Angulatus.) Having an angle, or corner, as the anterior of + the aperture of Eulima, fig. 348; the posterior side of Castalia, fig. + 140; the whorls of Carocolla, fig. 277. + + ANGULITES. Montf. A genus composed of species of fossil NAUTILI, + described by De Blainville as not umbilicated, with a dorsal keel and + angular aperture. NAUTILUS triangularis Buffon. + + ANGIOSTOMATA. Bl. The third family of Siphonobranchiata, Bl. described + as differing little from the family of Entomostomata, but having long, + narrow, straight apertures, and the columellar lips straight or nearly + so. Were it not for the admission of the genus Strombus into this + family, it would correspond with COLUMELLARIA and CONVOLUTÆ of Lamarck. + + ANNELIDES. The ninth class of invertebrated animals, divided into three + orders, namely, A. Apodes, A. Antennés, and A. Sedentaires. The last + only contains families of testaceous Mollusca. The animals are + vermicular, some naked, others inhabiting shelly tubes. See SEDENTARY + ANNELIDES. + + ANNULAR OPERCULUM is one which has the nucleus central, or nearly so, + the other layers surrounding it in flattened rings. The term concentric + is also applied. See Introduction. + + ANNULATED. (Annus, a ring.) Composed of, or surrounded by rings, as in + the case of Tubicinella, fig. 14. + + ANODON. Brug. _Fam._ Submytilacea, Bl. Nayades, Lam. A genus composed + of such species of NAYADES as are destitute of teeth on the hinge. + Europe, North America, &c. An example is given in A. Cataractus, fig. + 152. + + ANOMALINA. D'Orb. A genus of microscopic Foraminifera. + + ANOMIA. _Fam._ Ostracea, Lam. and Bl.--_Descr._ Irregular, inequivalve, + sub-equilateral, foliaceous, pearly within; adhering to marine + substances by means of a bony appendage, which passes through a large + circular opening in the lower valve; muscular impression divided into + three irregular portions; hinge destitute of teeth with a short + cartilage.--_Obs._ The Linnæan genus included not only the shells to + which the description above given would apply, but also many other + genera, such as Crania, Orbicula, Terebratula, &c. which belong to the + Brachiopoda, and are perfectly distinct. The Anomiæ are found in + Europe, N. America, Moluccas, Philippine Islands, &c. Fig. 186, in the + plates, is a somewhat reduced representation of a full grown specimen + of A. Ephippium. Fig. 187, the hinge of the under valve, with the bony + process. Fig. 188, the hinge showing the opening through which it + passes. + + ANOSTOMA. See ANASTOMA. + + ANSATES. Klein. A genus formed of those species of Patella which have a + produced, recurved beak. Helcion, Montf. _Ex._ Patella pellucida, fig. + 230. + + ANSULUS or ANSYLUS. Mr. Gray conjectures that the name of the genus + Ancylus, should be so written. + + ANTENOR. Montf. A genus of microscopic Foraminifera. + + ANTERIOR. In Bivalves is the side on which the head, or part analogous + to the head of the animal lies; it is known in the shell by the + umbones, which if turned at all, are turned towards that part. If there + be a sinus in the impression of the mantle, it is always on the + posterior part of the shell. If the ligament be placed only on one side + of the umbones, it is only on the posterior side. The anterior of a + _spiral univalve_ is that part of the outer lip which is at the + greatest distance from the apex. Of a _symmetrical_ conical univalve + such as Patella, it is that part where the head of the animal lies, + indicated by the interruption of the muscular impression. Of + _cirripedes_, that part where the ciliæ protrude are anterior; of + _Brachiopoda_, that part which is farthest from the umbones and which + corresponds with the ventral margin in other Bivalves. The anterior of + _symmetrical, convolute univalves_, is the outer or dorsal part of the + aperture, or that part which is farthest from the spire. Lamarck and + other Conchological writers have occasioned much confusion by their + errors on this subject; describing the same part of a shell at one time + anterior, at another posterior; but generally the reverse of the above + arrangement, which is founded upon the natural position of the animal, + and generally adopted. The anterior will be indicated by the letter + _a_, in figs. 119, 421, 229, 34, 202. + + ANTIGONA. Schum. A genus composed of VENUS cancellata, Lam. (fig. 119.) + and similar species. + + ANTIQUATED. This word, signifying _out of date_, is occasionally used + to express that species of composition which constantly occurs in + shells, by each fresh deposit or layer of calcareous matter, forming a + new margin, which being replaced by its successor, is no longer used as + the margin, and is consequently said to be out of date. + + APEX. This term does not apply to the natural position of a shell, but + is used in a mathematical sense, to indicate the nucleus or first + formed part; which may be considered as the point of the spiral cone. + From this point, the shell enlarging rapidly or slowly as it descends, + takes a spiral, arched, straight, oblique, convolute, or irregularly + spiral course. The apex will be indicated by the letter _a_, in fig. + 282 and 466. + + APERTURE or MOUTH. The entrance to the spiral cavity of univalve + shells. The parts of the aperture are separately described, as follows: + The inner lip or labium is that part which lies over the preceding + whorl of the shell. It terminates anteriorly, or towards the lower part + in what is termed the columella, so called because it forms a kind of + axis on which the volutions turn. The outer lip, sometimes called the + labrum, is on the opposite side, or the farthest from the axis. If the + edges of the inner and outer lips unite all round, they are described + as composing the peritrême. In fig. 318, the aperture is marked by the + letter a. + + APHRODITA. Lea. (from [Greek: Aphroditê], Greek name of Venus.) A genus + composed of CARDIUM Groenlandicum, Auct. fig. 123*, and other similar + species of Cardium, the teeth of which are either wholly wanting, or + very indistinct. Northern Ocean. + + APICIAL. Belonging to the apex. The apicial extremity of the aperture + of a univalve shell, is that which is nearest to the apex of the spire. + + APICULUM. Humph. TROCHUS, Lam. + + APLEUROTIS. Rafinesque. A genus unfigured and imperfectly described as + differing in some respects from Terebratula and other Brachiopodæ. + + APLEXUS. Fleming. A genus composed of PHYSA Hypnorum, Drap. &c. and + described as having the inner lip simple, and not spread over the body + whorl. + + APLODON. Rafinesque. A genus proposed to be established at the expense + of the genus HELIX, but upon what grounds does not appear from the + imperfect description which is unaccompanied by a figure. + + APLUSTRE. Schum. A genus formed for the reception of those species of + BULLA which have the spire uncovered. _Ex._ Bulla Aplustre, + (_aplustre_, a flag.) Auct. fig. 289. + + APLYSIA. Linn. (_a_, without; [Greek: Pluô], to wash.) _Fam._ + Laplysiens, Lam. Aplysiana, Bl.--_Descr._ Horny, transparent, + clypeiform, or shield-shaped, placed horizontally on the back of the + animal, with its convex side uppermost; apex slightly incurved.--_Obs._ + The animal producing this shell has derived its name from the purplish + liquor which it exudes, when disturbed. In contour, it has been fancied + to present a certain likeness to a hare crouching, and on this account + was called _Lepus marinus_, or sea hare, by the ancients. The shell + bears a strong resemblance to Dolabella, which, however, is much + thicker, and more testaceous. The species are found in the + Mediterranean, European, and West Indian Seas. A. Petersoni, fig. 254. + + APLYSIACEA. Bl. The second family of the order Monopleurobranchiata, + Bl. The animals composing this family are either destitute of shells, + or are provided with internal ones, which are flat, open, oblique, with + the apex or nucleus slightly incurved, not distinctly spiral. This + family contains the genera, Aplysia and Dolabella. The first + sub-spiral, with the apex terminal; shell thin, horny. Fig. 254. The + second the same, but thick and shelly. Fig. 255. + + APOLLON. Montf. RANELLA Ranina, Auct. Placed by De Blainville in that + division of Ranella, which is characterized as being umbilicated. Fig. + 393. + + APOROBRANCHIATA. Bl. The first order of the second section of + Paracephalophora Monoica, Bl. The Thecosmata is the only family of this + order containing any approach to shells, these are Hyalæa and Cymbulia. + + APORRHAIS. Petiver. A genus formed of ROSTELLARIA Pes-pelicani, _Auct._ + (fig. 404) and similar species. Although the shell presents no + characters to distinguish it generically from Rostellaria, those who + have examined the soft parts are convinced that it is distinct. Of the + three species now known and figured in part I. of Thesaurus + Conchyliorum, by the Author, one is common on our own coast, and in the + Mediterranean; also North America. See ROSTELLARIA. + + AQUATIC. A term applied by some authors to those species of Molluscous + animals, which inhabit fresh water, either in rivers, or salt water + standing pools, as distinguished from the marine or Mollusca. See + Fresh-water. + + AQUILLUS. Montf. TRITON Lampas, Cutaceus, &c. Auct. Placed by De + Blainville in the division of the genus Triton, which is described as + having a short spire, being covered with tubercles and umbilicated. + Triton Cutaceus, fig. 399. + + ARCA. Auct. (Anglicè, a boat.) _Fam._ Arcacea, Lam.--_Descr._ Obliquely + transverse, subquadrate, equivalve, or nearly so, inequilateral, thick, + ventricose, longitudinally ribbed, dentated near the inner margins; + hinge rectilinear, forming a flat, external area, upon which the + ligament is spread in cross rows, and having a series of small, regular + teeth, extending on both sides of the umbones in each valve; muscular + impressions distant.--_Obs._ The shells composing this genus are easily + distinguished from those of all other bivalve shells, by the straight, + linear row of small, notched teeth, and by the area between the + umbones. The genus _Cucullæa_ makes the nearest approach to it in this + respect, but it may easily be known from it by the outermost teeth on + each side of the row being oblique, and lengthened out; and also by the + prominent edge of the muscular impression. These shells are found + recent, in various marine localities; fossil, in the tertiary deposits. + The Arca Noæ, formerly regarded as the type of this genus, has, with + several other species, been separated from it under the name of + Bysso-arca, by Swainson, on account of an hiatus in the ventral margin, + to admit the passage of a byssus; this is not found in the true Arcæ. + The true Arcæ are mostly tropical. Arca Antiquata, fig. 131. Bysso-arca + Noæ, 132. + + ARCACEA. Lam. A family of the order Conchifera Dimyaria, characterized + by a series of teeth placed on the hinge in a line. The genera may be + distinguished as follows, + + 1. ARCA. Hinge straight; valves close. Fig. 131. + + 2. BYSSO-ARCA. Valves gaping. Fig. 132. + + 3. CUCULLÆA. Distant teeth oblique; posterior muscular impression + prominent. Fig. 133. + + 4. PECTUNCULUS. Hinge curved. Fig. 134. + + 5. NUCULA. The same, with a pit in the centre of the hinge, + including Myopara and Crenella. Figs. 135 to 137. + + 6. SOLENELLA. Fresh water, oval; a series of teeth on one side of + the hinge, only two or three on the other. Fig. 138. + + ARCHAIAS. Montf. A genus of microscopic Foraminifera. + + ARCHONTE. Montf. HYALÆA, Auct. + + ARCINELLA. Schum. CHAMA Arcinella, Auct. + + ARCTICA. Schum. CYPRINA Icelandica, Auct. + + ARCUATED. (Arcus, an arch.) Bent in the form of an arch, as Dentalium, + fig. 2. + + AREA. A flat space or disc, on any part of a shell. As for instance, + the triangular space on the hinge of Arca, fig. 132, and Spondylus. + + ARENACEOUS. (Arena, sand.) Of a sandy texture, as the sand tubes + surrounding the bodies of some of the Annellides, named Arenaria on + this account. But the word is more commonly used to intimate the habits + of the animal, burrowing with its shell in the sand. + + ARETHUSA. Montf. A genus of microscopic Foraminifera. + + ARGONAUTA. Auct. Commonly called the "Paper Sailor." _Fam._ Pteropoda, + Bl. _Order_ Cephalopoda Monothalamia, Lam.--_Descr._ Light, thin, + transparent or nearly so, symmetrically convolute, carinated by a + double row of tubercles, terminating smooth or tuberculated ribs + radiating towards the centre; aperture large, elongated; peritrême + acute, interrupted by the body whorl.--_Obs._ The exquisitely + beautiful, light and delicate fabrics included under the above name are + inhabited by a molluscous animal named the _Ocythöe_, which is provided + with tuberculated arms. These, hanging over the sides of the aperture, + give to the whole the appearance of a vessel propelled by oars: a + poetical illusion further heightened by the broad, flat membranes of + the two arms, which, when vertically expanded, present an idea of + sails. Pliny has described the Nautilus (the name has been changed by + the moderns) as sailing gracefully on the Mediterranean waters; and + Pope has versified the idea in the well known lines + + "Learn of the little Nautilus to sail, Spread the thin oar and + catch the driving gale." + + Scientific men have long been engaged in the interesting discussion, + whether the animal really belongs to the shell in which it is found, or + whether, having destroyed the rightful owner, it has possessed itself + of the "frail bark." It is now, however, proved beyond the shadow of a + doubt that the Argonaut is the testaceous part of the Ocythöe, and that + the broad membranes which in some representations have been + artificially placed as sails, are naturally bent backwards over the + shell like the mantle of some other molluscs. The interesting + experiments of Madame Power, in the Mediterranean, have contributed + very materially to lead the investigations of Naturalists to a + satisfactory conclusion. This lady kept a cage under water, in which + Argonautæ were bred in great numbers, giving her an opportunity of + tracing the gradual development of the shell in all its stages, from + the elastic and transparent nucleus to the full grown "Paper Sailor." + Fig. 485. + + ARIANTA. Leach. A sub-genus of land shells, containing HELIX + arbustorum, Auct. (Gray, Turton, p. 137.) + + ARION. A genus of slugs which have no shells. + + ARROW-HEADS. One of the names by which fossils of the genus Belemnites + were formerly known. + + ARTEMIS. A genus of bivalve shells, distinguished from those of the + genus Venus, by having a rounded, denticular form, and a deep, angular + sinus in the palleal impression. This does not appear to me to be a + sufficient ground of generic distinction, the palleal impressions of + the Veneres being subject to great variations. British, also from West + Indies, South America, Australia, &c. A. lincta, fig. 118. + + ARTICULATED. (Jointed.) Applied to distinct parts of shells, which are + fitted or jointed into each other, as the valves of Chitones and those + of Balani. The operculum of Nerita is said to be _articulated_ to the + columella, having a small process by which it is as it were locked + under the edge. See _Introduction_. The word is also applied to the + Cirri, which protrude from the oral openings of Cirripedes. + + ARTICULINA. D'Orb. A genus of microscopic Foraminifera. + + ASIPHONIBRANCHIATA. Bl. The second order of Paracephalophora Dioica, + Bl. Consisting of spiral univalves, which have no notch or canal at the + anterior part of the aperture. This order is divided into the families + Goniosomata, Cricosomata, Ellipsostomata, Hemicyclostomata, and + Oxystomata. + + ASPERGILLUM. Lam. (From _Aspergo_, to sprinkle.) _Fam._ Tubicolæ, Lam. + Pyloridea, Bl.--_Descr._ The small, equal, equilateral valves are + cemented into, so as to form part of, a large tube; the umbones are + slightly prominent outside. The tube is elongated, rather irregular, + granulated with sandy particles, and terminated at the base by a convex + disc, which is perforated by small pores, elongated into tubes round + the edge, presenting a resemblance to the spout of a watering pot, + whence the name is derived. _Loc._ New Holland, Java, New Zealand, Red + Sea. Fig. 44. Aspergillum Vaginiferum. + + ASSIMINEA. Leach. _Fam._ Turbinacea, Lam.--_Descr._ Inclining to oval, + light, thin, covered with a horny epidermis, spire produced into an + acute pyramid; whorls slightly angulated in the centre, rounded + beneath; aperture elliptical, slightly modified by the last whorl; + inner lip planed; outer lip thin; operculum horny, subspiral. Found in + brackish water; one species may be procured abundantly on the muddy + shores of the Thames, in Kent. There are also species from Calcutta, + China, Tahiti, and Australia. Without comparing the animals, it is + difficult to distinguish this genus from some species of Littorina. + Fig. 363. A. Grayana. + + ASTACOLUS. Montf. A genus of microscopic Foraminifera. CRISTELLARIA + Crepidula, Lam. + + ASTARTE J. Sowerby. (Name of a Sidonian Goddess, _Ashtaroth_ in + Scripture.) _Fam._ Nymphacea, Lam. Genus Crassina, Lam.--_Descr._ + Suborbicular, equivalve, inequilateral, thick, compressed; hinge with + two solid diverging teeth in the right valve, one tooth and a slight + posterior elevation in the left; muscular impressions, two in each + valve, uniform, united by a simple palleal impression; ligament + external.--_Obs._ This genus differs from Venus, Cytheræa, &c. in not + having a posterior sinus in the impression of the mantle. The hinge + also differs in having but two cardinal teeth. Astarte differs from + Crassatella in having no internal cartilage in the hinge. Some of the + species are British, others are from America, and one from Sicily. The + fossils occur in Crag, Lower Oolite, &c. Fig. 110. A. Danmoniensis. + + ASTROLEPAS. Klein. CORONULA Testudinaria, Auct. CHELONOBIA, Leach. Fig. + 15. + + ATLANTA. Lesueur. _Fam._ Pteropoda, Lam. and Bl.--_Descr._ Spiral, + convolute, transparent, fragile, compressed, with a broad, fimbriated, + dorsal keel, and a narrow aperture. This shell, which is called "_corne + d'ammon vivant_," is found in the Atlantic. The small Pteropod, figured + in Sowerby's Genera as Limacina, belongs to this genus. Atlanta + Helicialis, fig. 220. + + ATRACTODON. Charlesworth. (Mag. Nat. Hist. 2nd series, Vol. 1. p. 218. + ) A genus proposed for the admission of a singular fossil shell, found + on the beach at Felix-stone, of which the following are the + characters;--fusiform, aperture equalling the spire in length, + terminating anteriorly in a slightly recurved canal; columellar lip + smooth, curved, thickened posteriorly into a blunt tooth; spire + obtuse.--_Obs._ This shell would be a Fusus were it not for the tooth + on the posterior extremity of the columellar lip. The only species + known is regularly striated in a spiral direction, and named A. + Elegans. + + ATRYPA, Dalman. A genus of brachiopodous bivalves, distinguished by the + valves being nearly equal, and the umbones not separated by an + intermediate area. A. reticulata, fig 302. + + ATTACHED. Shells are attached to marine substances by various means; in + some cases by a _byssus_, or a bunch of tendinous fibres passing + through an opening between the valves, which gape at their margins to + admit a free passage, as in the genera Byssoarca and Mytilus. In other + cases the byssus is of a more compact substance, and passes through a + perforation in the shell itself. This is the case with many of the + brachiopodous shells, in some species of which the perforation is in + the point of the umbones, a specimen of which is represented in the + Introduction. This species of attachment does not keep the animal + motionless, although it is confined to a particular spot. Other shells + are attached by a portion of their own substance, as in Chama, + Spondylus, Serpula, &c. in which instances, the attached valve is + motionless, and is termed the under valve. The Pedunculated Cirripedes + are attached by a tubular tendinous process, called a peduncle. + + ATTENUATED. Drawn out, long, thin, tapering, as the extremities of + Ovulum Volva, fig. 442. + + ATYS. Montf. A generic name including those species of BULLA, which are + described as "convolute, with the last whorl covering the rest and + hiding the spire, the apex rounded at both ends." Bulla Naucum, Auct. + fig. 250. + + AURICLE. (A little ear.) See AURICULATED. + + AURICULA. Lam. (Dim. from _Auris_ an ear.) _Fam._ Auriculacea. Bl. + Colimacea, Lam.--_Descr._ Oval or oblong, cylindrical or conical; + aperture long, narrow, generally narrowest in the centre; rounded + anteriorly, with two or three strong folds on the inner lip, and the + outer lip thickened, reflected or denticulated; spire short, obtuse, + epidermis horny, brown.--_Obs._ The above description includes the A. + coniformis, f. 298. and several other conical species with narrow + apertures which formed the genus _Melampus_, Montf. and _Conovulus_, + Lam. The latter author suppressed his genus on ascertaining the + Conovuli to be land shells. We exclude, however, the A. Dombeyana, Lam. + f. 300. and several similar species, which being more rounded, having + thin outer lips and but one fold on the columella, are described under + the generic name _Chilina_, Gray. It appears rather doubtful whether + the Auriculæ are marine or fluviatile, but the animals appear to be + amphibious. The Auriculæ are principally found in Salt Marshes of + Tropical climates, some small species are found on the Southern + European Coasts, as far north as Britain and south as Tierra del Fuego. + The Auriculæ formed a part of the genus Voluta of Linnæus, f. 297. A. + Judæ, f. 298. A. Coniformis. + + AURICULATED. Some bivalve shells, such as _Pecten_, fig. 171, 172, have + a flat, broad, somewhat triangular appendage on one or both sides of + the umbones, called an _auricle_, or little _ear_. If on one side only, + they are said to be _uni-auriculated_; if on both, they are said to be + _bi-auriculated_. + + AURICULACEA. Bl. The second family of the order Pulmobranchiata, thus + described; "shell thick, solid; aperture more or less oval, always + large, rounded anteriorly, and contracted by teeth or folds on the + columella." This family is included in the genus Voluta of Linnæus, on + account of the plaited columellar lip, a character by which that + heterogeneous assemblage of shells is distinguished. It forms part of + the family of _Colimacea_, Lam. from which they differ not only in + general form, but also in the fact of the animals being partly + amphibious, always living (according to De Blainville) on the sea + shore, and being occasionally covered with water for a short time. It + contains the genera Pedipes, Auricula, Pyramidella. + + AURIFERA. Bl. OTION, Auct. + + AURIFORM. (From _Auris_, an ear; _forma_, shape.) Ex. _Haliotis_, fig. + 338. + + AURISCALPIUM. Megerle. ANATINA, Lam. + + AVICULA. Lam. (From _Avis_, a bird). _Fam._ Malleacea, Lam. + Margaritacea, Bl.--_Descr._ Inequivalve, inequilateral, foliaceous, + subquadrate, oblique, pearly; hinge rectilinear, lengthened into + auricular appendages, with a small indistinct tooth in each valve, an + elongated, marginal, ligamentiferous area, and an hiatus in the left + valve, for the passage of a byssus; one circular muscular impression, + near the centre of each valve, with a series of smaller ones arranged + in a line towards the umbones.--_Obs._ The Meleagrinæ of Lamarck, + Margaritiferæ, Schum. included in this description, consist of the more + rounded species, and do not present the elegant obliquity of form, nor + the wing-like auricles from which the genus Avicula receives its name. + The Aviculæ are pearly within. From A. margaritifera, a young specimen + of which is figured in the plates, fig. 164, is obtained oriental + pearls. This is an example of Meleagrina. A. Hirundo, fig. 163, belongs + to the genus Avicula of Lamarck. It is, however, needless to continue + the separation. Aviculæ are from E. and W. Indies, Mexico, Coasts of + the Pacific, Mediterranean, British Islands, &c. Fossil species occur + in the London clay, &c. + + AXINUS. J. Sowerby.--_Descr._ Equivalve, transverse; posterior side + very short, rounded, with a long ligament, placed in a furrow, + extending along the whole edge; anterior side produced, angulated, + truncated, with a flattish _lunule_ near the beaks. The late Mr. James + Sowerby, who described this shell in the Mineral Conchology, did not + consider his genus as established, not having seen the hinge. + + AXIS. The imaginary line, round which the whorls of a spiral shell + revolve. The extremities of the axis are pointed out in fig. 379, by + the letters, _a. a._ See "COLUMELLA." + + AZECA. Leach. _Fam._ Colimacea, Lam.--_Descr._ "Animal like Bulinus, + with subcylindrical, rather obtuse shell, covered with a polished + periostraca (epidermis); aperture pear-shaped, curved and pointed at + the top; the margin thick, obtuse, united all round and toothed; the + axis imperforated." Gray's edition of Turton's British Shells, page + 189.--_Obs._ The Turbo Tridens of Montagu, upon which this genus is + founded, resembles Bulinus lubricus in general form and character. Both + these shells differ from the true Bulini in having the peritreme + entire, and in being pellucid and glossy. Azeca differs from Bulinus + lubricus in having three teeth in the aperture, two on the inner lip + and one on the outer. Not seeing the necessity for creating a genus on + grounds so slight, I have simply transcribed the description given + above, leaving others to form their own conclusions as to the propriety + of separating this shell from the genus Bulinus. Britain, Central and + Southern Europe. Azeca Tridens, fig. 290. + + AZEMUS. Ranzani. CONIA, Leach. + + BACULITES. Lam. _Fam._ Orthocerata, Bl. Ammonacea, Lam.--_Descr._ + Straight, conical, tubular, laterally compressed; chambers divided by + very sinuous lobed septa, the last elongated; aperture elliptical; + siphon dorsal.--_Obs._ This genus differs from Orthoceras in the same + manner in which Ammonites differs from Nautilus, having its septa + sinuated and branched. A Baculite might be described as a straight + Ammonite. This genus is known only in a fossil state. It is found in + the Cretaceous Limestone of Maëstricht and Valognes. Fig. 484. B. + Faujasii. + + BALANUS. Brug. (an Acorn; "gland de Mer." Fr.) _Order_ Sessile + Cirripedes, Lam. _Fam._ Balanidea, Bl.--_Descr._ Shell composed of six + valves articulated to each other side by side in a circle, by the + insertion of lamina; closed at the base by a flat, cylindrical or + cup-shaped valve, by which it is generally attached; and at the apex by + a conical operculum, consisting of four valves in anterior and + posterior pairs. Each valve of the shell is divided into a rough + triangular portion pointed towards the apex, and a flat area on each + side.--_Obs._ This description includes the _Acasta_ of Leach, which + growing in sponges, has the base cup-shaped; _Conoplæa_ of Say, which + being attached to the stems of Gorgonia and sea-weeds has the base + elongated and lanceolate, and _Chirona_, Gray. Balanus is the only + genus of Sessile Cirripedes the shells of which consist of six parietal + valves, except _coronula_, which has no shelly base, is flatter, and + has the valves of the operculum placed horizontally. The Balani are + common in all seas, adhering to rocks, corals, floating timber, and to + each other. The fossil species are found in the newest strata, at + Bordeaux, Paris, &c. Fig. 25. B. Tintinnabulum; 26. _Acasta_ Montagui; + 27. Balanus galeatus, _Conoplæa_, Say. + + BALANIDEA. Bl. The second family of the class Nematopoda, Bl. + corresponding with Sessile Cirripedes, Lam., and consisting of + Coronular Multivalves, which are fixed, and in a manner soldered to + submarine substances, by the base of the shell; as distinguished from + the Lepadicea, Bl., Pedunculated Cirripedes, Lam., which are attached + by a fleshy stalk. The Balanidea are composed of two sets of valves, + besides the shelly plate or base on which they rest. The first, called + the Parietal valves, are arranged so as to surround the body of the + animal; the second, called the Opercular valves, are placed + horizontally, so as to cover the aperture. + + BALEA. Gray. _Fam._ Colimacea, Lam.--_Descr._ Spiral, turrited, + concentrically striated, sinistral, and covered with a thin brown + epidermis; spire composed of numerous whorls, gradually increasing in + size; aperture small, sub-quadrate; peritrême entire, slightly + thickened, with a very slight fold on the columella; axis + perforated.--_Obs._ A genus of small land shells, found in moss at the + roots of trees in Britain, not very nearly resembling any other land + shells, except Clausilia, from which they differ in not having the + clausium. They have been placed in Helix by De Ferrusac, and in Pupa by + Draparnaud. B. fragilis, fig. 296. _Helix perversa_, Fer. _Pupa + perversa_, Drap. + + BARBATA. Humphrey. UNIO, Lam. + + BARNACLES. PENTELASMIS, Auct. (fig. 34.) Called Anatifa, by Linnæus and + Lamarck, from the ancient notion that they were the eggs or embryo of + the Barnacle Duck. See ANATIFER. + + BASE. In all shells which are attached to sub-marine substances, the + base is that part of the shell which forms the point of attachment,--as + for instance, the attached valve of Spondylus, the basal plate of + Balanus, the lower part of the peduncle of Pentelasmis; in Unattached + Bivalves, the margin opposite to the umbones, where the foot of the + animal, or the part analogous to it, protrudes; in spiral univalves, + the aperture, which rests on the back of the animal when walking. + Lamarck and some other authors have used the term _base_ as simply + opposed to apex, and apply it to the anterior of the aperture. + + BATOLITES. Montf. HIPPURITES, Auct. + + BEAK. The Apices, or points of the valves of a bivalve shell, generally + termed UMBONES, in descriptions. Also any part which is rostrated or + drawn out like a beak. + + BEAKED. See BEAK and ROSTRATED. + + BEAR'S-PAW-CLAM. The common name for Hippopus maculatus, a + representation of which is given in the plates, fig. 156. + + BELEMNITES. Auct. ([Greek: Belemnon], _belemnon_, a dart, or arrow.) + _Fam._ Orthocerata, Bl. and Lam.--_Descr._ Straight, conical, + consisting of two parts; the _external_ portion forming a thick solid + sheath, with a cavity at the base to admit the internal portion or + nucleus, which is mathematically conical, and is divided into chambers + by smooth simple septa perforated by a lateral siphon.--_Obs._ These + singular fossils, which are found in most secondary beds, have long + attracted the attention of philosophers as well as of the ignorant, + from whom they have received the various appellations of + Thunder-Stones, Petrified Arrows, Petrified Fingers, Devil's Fingers, + Spectre Candles, &c. The above description is framed to include the + genera Hibolithes, Porodragus, Cetocis, Acamas, and Paclites of De + Montfort, and Actinocamax, Stokes. Fig. 466 to 468. + + BELLEROPHON. Montf. (or Bellerophus).--_Descr._ Convolute, symmetrical, + umbilicated, with a double dorsal ridge; aperture wide, + semilunar.--_Obs._ The fossils composing this genus resemble Nautilus + in general appearance, but not being chambered shells they approach + very near to Argonauta, from which they differ only in the thickness of + their shell and in roundness of their external form. This genus is + erroneously placed by De Montfort among chambered shells, and by De + Blainville next to Bulla. It belongs to the Monothalamous Cephalopoda + of Lamarck. This fossil is found principally in the Carboniferous + Limestone. Fig. 486, 487, represent B. tenuifasciata. + + BELOPTERA. The bony support of a species of Cuttlefish, partly + resembling Sepia. + + BIAPHOLIUS. Leach. A genus believed to be identical with Hiatella. + + BI-AURICULATED. Having two auricles placed at the sides of the umbones, + as in Pecten, fig. 171. See AURICULATED. + + BICATILLUS. Sw. A sub-genus of "Calyptrædæ," including those species, + which have cup-shaped internal septa, as for example, Calyptræa + extinctorium, fig. 235. + + BICONIA. Sw. A sub-genus of "Calyptrædæ," including those species in + which the septum is partly spiral. + + BIFID. Divided, double. + + BIFRONTIA. Deshayes. Also OMALAXIS, Desh. _Fam._ Turbinacea, + Lam.--_Descr._ Discoidal, planorbicular, with whorls sometimes not + contiguous; umbilicus deep, keeled at the margin; aperture + subtriangular, somewhat dilated; outer lip acute, separated by a deep + notch at both extremities.--_Obs._ We do not see any reason for + separating this genus from SOLARIUM, except the last mentioned + character. The few fossil species which this genus contains (Solarium + disjunctum, Bifrons, &c.) are found principally in the Paris basin. + Fig. 354. Solarium Bifrons. + + BI-FURCATE. Double pronged, or having two points. _Ex._ the internal + appendage of Calyptræa Equestris, fig. 234. + + BIGENERINA. D'Orb. A genus of microscopic Foraminifera. + + BILABIATED. Having the edge of the outer lip as it were doubled, by one + part of the lip being more thickened and reflected than the other, so + as to form a ledge, or second lip. + + BILOBATE. Having two prominent parts, as the outer lip of Rostellaria + Pes-Peleeani, fig. 404. + + BIPARTITE. Composed of or divided into two parts; double; as the valves + of Platylepas, fig. 19, each of which has a septiform division in the + centre; also the area on the hinge of Spondylus. See Frontispiece. + + BIROSTRA. Sw. A genus composed of species of OVULUM, which have + elongated extremities, as, for instance, Ovulum Volva, fig. 442. + + BIROSTRITES. Lam. (Double Beak.) A fossil formerly considered as a + distinct bivalve shell, with conical umbones, and placed in the family + of Rudistes by Lamarck, but now known to be an internal cast of + Sphærulites, fig. 196. + + BISIPHYTES. Described by De Montfort as resembling a Nautilus, but + having two distinct siphons. As no such fossil species is now known to + Naturalists, it appears probable that De Montfort having a specimen of + some Nautilus, with an accidental depression, took it for a second + siphon. + + BITHINIA. Gray. A genus described as differing from PALUDINA, in having + the operculum shelly, and the mouth of the shell thickened internally. + PALUDINA impura, Auct. Fig. 537. + + BITOMUS. Montf. A microscopic shell, deriving this general appellation, + from the appearance of a double aperture. + + BIVALVE. A shell composed of two equal, or nearly equal principal + parts, each part having a separate nucleus, turning upon each other by + means of a hinge. The class Conchifera of Lamarck, Acephalophora of De + Blainville severally include the whole of the bivalve shells; the + latter name being derived from the fact that the animals have not + distinct heads, and neither eyes nor tentacula. All bivalve shells are + marine or fresh-water. They form the class Dithyra of Aristotle. It may + be observed that some of the Acephalophora, the Pholades, for example, + have small testaceous pieces fixed on the hinge, which are called + accessary valves. These are still fairly bivalve shells, although the + genus Pholas has been placed by some writers among the multivalves. + + BOAR'S TUSK. A common name given to shells of the genus Dentalium. One + particular species has received a specific name in accordance with a + supposed resemblance, namely, Dentalium Aprinum, (of a Boar.) + + BONELLIA. Desh. A genus formed, in the first instance, for the + reception of Bulinus terebellatus, Lam. which Mr. G. B. Sowerby, in his + Genera of Shells, united with the genus PYRAMIDELLA. M. Deshayes, + however, in his new edition of Lamarck, makes the genus Bonellia + include several species which I have arranged in the genus Eulima. From + the remarks of M. Deshayes, tom. 8, p. 286, 287, we are led to suppose + that the estimated difference between Eulima and Bonellia consists in + the latter having the axis perforated; or in other words, umbilicated. + After remarking "que Mr. Sowerby, junr. confond deux choses bien + distinctes, sous le nomme d'Eulima," M. Deshayes gives the following + description of his genus, (translated) "shell turriculated, smooth, + polished, with the apex acute and laterally inclined; axis perforated + throughout its length; aperture small, entire, angular at the + extremities; columella simple and without folds; outer lip thin, + simple, nearly parallel with the longitudinal axis." That author + further remarks, "Mr. Sowerby, junr. à signalé cinque espèces vivant, + que nous rapportons à notre genre." (Sowerby, junr. Conchological + Illustrations, parts 52 and 53; 50, Great Russell Street, Bloomsbury.) + The species thus selected are E. splendidula, E. marmorata, E. + interrupta, E. imbricata, E. brunnea; the two last of which have the + umbilicus so inconsiderable, as to be scarcely distinguishable from + other species, which M. Deshayes has left in the genus Eulima, and + which have a slight hollow, almost approaching to a perforation, behind + the columella. Eulima marmorata, (Bonellia, Desh.) is figured in the + plates, fig. 348. + + BODY WHORL. The last whorl, constituting the bulk of the shell. + + BORELIS. Montf. MELONIA, Bl. A genus of microscopic Foraminifera. + + BORER or PIERCER. A term applied to those species of Acephalopodous + Mollusca, which bore holes as dwellings in the rocks, as the Pholades, + and some others. + + BRACHIOPODA. Lam. A family of symmetrical bivalves belonging to the + third section of Lamarck's _order_ "Conchifera Monomyaria," described + as bivalve (generally symmetrical) adhering to marine bodies, by a + tendon passing through the shell, having no true ligament. What most + distinguishes this family and renders it remarkable is the structure of + the animal. It has two elongated, tendril-shaped arms. When the animal + is in a state of repose these arms are coiled up spirally and enclosed + in the shell, but when required for use, are unfolded and extended. + This family contains the genera Orbicula, Terebratula and Lingula, in + the system of Lamarck, to which may be added Thecidium, Productus, + Spirifer, Magas, Pentamerus, Crania, Strigocephalus, Strophomena, and + some others enumerated in the explanation of figures 201 to 219. The + above genera may be thus distinguished. + + 1. ORBICULA. Umbones central; byssus passing through a hole in the + flat valve. Fig. 201. + + 2. ATRYPA. Without foramen or space between the valves. Fig. 203. + + 3. PRODUCTA. The same, valves produced, overwrapping; including + Leptæna. Fig. 206, 206*. + + 4. TEREBRATULA. Hinge of the upper valve produced beyond that of + the other, with a pit or foramen; including _Delthyris_, _Orthis_, + _Trigonosemus_, _Magas_, _Strophomena_. Fig. 202, 205, 207, 208, + 209. + + 5. SPIRIFER. The same, with deep triangular area; spiral folds in + the interior; including _Trigonotreta_ and _Cyrtia_. Fig. 204, 214, + 215. + + 6. THECIDIUM. Large valve attached; curved ridges in the inner + surface; two jutting points or teeth on the hinge. Fig. 216. + + 7. CRANIA. Attached by the surface of the valve; muscular + impressions four, forming a face. Fig. 197, _a_, b. + + 8. PYCNODONTA. Irregular; hinge with raised pointed teeth. Fig. + 217, 218. + + 9. PENTAMERUS. Valves divided by septa; including _Gypidia_. Fig. + 210 to 213. + + 10. LINGULA. Valves equal, gaping, with a peduncle. Fig. 219. + + BRACHITOMA. Swainson. A genus composed of PLEUROTOMA strombiformis and + similar species, described as "sub-fusiform; resembling a small + Strombus or Fusus; spire and aperture of equal length; canal short; + outer lip slightly ascending, and forming a short canal; sinus very + small and nearly semicircular; inner lip thickened above. B. + Strombiformis, Sow. Man. fig. 381." Europe, East and West Indies, + China, &c. + + BRANCHIFERA. Bl. The second family of the order Cervicobranchiata, + containing the following genera of symmetrical univalves:--Fissurella, + Emarginula, and Parmophorus. + + BRISMÆUS. Leach. _Order._ Pedunculated Cirripedes. Lam.--_Descr._ Seven + plates, three pairs lateral, one dorsal; form cylindrically conical; + pedicle not described. _Hab._ Holes in corals. B. Rhophodius, fig. + 38.--_Obs._ This minute shell most nearly resembles Pollicipes + Mitellus, fig. 37*, but the difference may be seen at once by comparing + the figures. + + BRONTES. Montf. This generic name is given to such species of MUREX as + have a very long, closed canal; with a short spire, circular aperture, + and are destitute of spires and ramifications. Brontes (Murex) + Haustellum, fig. 390. + + BUCARDIA. Schum. ISOCARDIA, Auct. + + BUCCINUM. Linn. _Fam._ Purpurifera, Lam. Entomostomata, Bl.--_Descr._ + Subovate or oblong, covered with an epidermis; spire turrited, + consisting of few whorls; aperture wide, subovate, terminating + anteriorly in a very short canal, reflected over the back; outer lip + simple, slightly reflected; inner lip spread over a portion of the body + whorl, terminating in a thick, smooth columella; operculum horny. + _Hab._ British Seas, Northern Ocean, and Coast of Africa. Most of the + fossil species occur in Crag, some in upper marine formation and London + clay.--_Obs._ There are considerable difficulties in keeping this genus + distinct from others nearly related to it, into which many of the + species run by imperceptible gradations. The genus _Nassa_ has been + separated on account of the little notch, which terminates the + columella. Some species of Terebra come so close upon the Buccina, that + it is difficult to say where one genus ends and the other begins. T. + Buccinoides, fig. 427. Buccinum Undatum, the common Whelk, fig. 421. + + BUFO. Montf. A generic division of the species composing Ranella, + characterized as having the shell not umbilicated. _Ex._ R. ranina, + fig. 394. The above character is scarcely sufficient in some cases, + even as a specific distinction. + + BULBUS. Humph. RAPELLA, Swainson. A genus formed for the reception of + PYRULA papyracea, Auct. (fig. 389), and similar species. RAPANUS, + Montf. + + BULIMIMA. Montf. A genus of microscopic Foraminifera. + + BULIMULUS. Leach. _Fam._ Colimacea, Lam. The author is unacquainted + with the characters by which the two or three species included in this + genus are to be distinguished from Bulinus. We have represented, fig. + 283, Bulimulus trifasciatus, Leach, (Bulinus Guadaloupensis, Auct.) + This occurs in the same limestone which encloses the half fossilized + human remains from the Grand Terre of Guadaloup. Several species are + described by the Rev. L. Guilding in the Zoological Journal, namely, + the B. Undulatus, Antiguensis, and Proteus; but neither from the shells + themselves, nor from the figures of the animal, can we draw any + information as to the generic character; the difference alleged by Mr. + Swainson and Mr. Gray being a comparative thinness in the outer lip. + + BULINUS. Brug. (Bulinus, Lam.) _Fam._ Colimacea, Lam. Limacinea, + Bl.--_Descr._ Oval or oblong, light, covered with a thin epidermis; + spire obtuse, variable in length and in the number of whorls, which are + generally few; aperture wide, oval, rounded anteriorly; outer lip + simple, usually reflected, joining the columella without a sinus; inner + lip reflected over part of the body-whorl. The Bulini are land shells, + found in many parts of the world.--_Obs._ The genus Bulinus can only be + distinguished from Helix by its oval form; it forms part of the genus + Helix of De Ferrusac, under the sub-generic designation of Cochlostyla. + It is known from Achatina by the absence of the notch at the point of + union between the inner and the outer lips. The young are produced from + eggs, which are as firm and opaque as those of birds. (See + Introduction.) Bulinus rosaceus, fig. 282. B. Guadaloupensis, fig. 283. + B. Lionetianus, fig. 284. B. lubricus, fig. 285. Many new species were + brought to this country by Mr. Cuming, and are represented in the + Conchological Illustrations, published by the Author at 50, Great + Russell Street, Bloomsbury, (in parts 21, 22, 23, 26, 27, 30, 31, 34, + 35, 137 to 146, 185, 186.) Species occur in Europe, West Indies, + Brazil, and South America generally. Some small species are British. + + BULLA. Auct. _Fam._ "Bulléens," Lam. Akera, Bl.--_Descr._ Generally + thin, smooth, oval, oblong or cylindrical, more or less convolute; + spire short, depressed, or hidden by the last whorl; aperture long, + wide in front, gradually narrowing towards the spire; outer lip thin; + inner lip spread over a part of the last whorl.--_Obs._ The shells + composing this genus are very variable in form. The light horny species + with an elastic lip is called Akera, fig. 247. The more decidedly + convolute species with hidden spires are the Atys, Montf. B. Naucum, + fig. 250. B. Lignaria, fig. 251, is Scaphander of Leach. The light, + thin species, with extremely wide aperture, fig. 248, is Bullæa aperta, + Lam. The genus Bullinula of Dr. Beck, consists of those species which + have more produced spines, fig. 253. The Bullæ are marine, and inhabit + all climates. The fossil species occur in tertiary beds. + + BULLÆA. Lam. BULLA aperta, Auct. fig. 248. + + BULLÆANA. ("Bulléens, Lam.") A family belonging to the first section of + Lamarck's order, Gasteropoda, containing the genus Bulla. The genera + Bullæa, Akera, Aplustra, Atys, Scaphander, Bullinula, into which it has + been divided, may all be fairly included under the name BULLA. + + BULLIA. Gray. A genus of shells partly resembling Buccinum, and Terebra + in general form, being more elongated than the former and more + ventricose than the latter. Mr. Gray remarks in the Synopsis of the + British Museum, page 114, that the Bulliæ resemble the Nassæ in most + characters, "but they have a very large, broad foot, and the hinder + part of the inner lip of the shell being extended beyond the mouth, + forms a raised enamelled band round the suture of the whorls, as is + also the case with the Ancillariæ and some Volutes." Bullia vittata, + fig. 427, is an example of the genus. The name Subula is given by De + Blainville to the other species of Terebra, so that if both these + genera were admitted, the old genus Terebra must be expunged. + + BULLINULA. Beck. Species of BULLA, with produced conical spires, fig. + 253. + + BYSSOARCA. Sw. (_Byssus_ and _Arca_.) _Fam._ Arcacea, Lam. A genus of + bivalve shells, composed of the Arca _Noæ_, and several other species, + separated from the genus Arca on account of their shells being attached + by means of a byssus passing through an hiatus in the ventral margins. + B. _Noæ_, fig. 132. The species occur in Southern Europe, East and West + Indies, China; also, on the coasts of Great Britain. + + BYSSOMYA. Cuvier. (_Byssus_ and _Mya_.) De Blainville states that + although the shell of this proposed genus resembles Saxicava, the + animal is sufficiently different to justify the separation. + + BYSSUS. ([Greek: Bussos], _byssus_, ancient name for linen.) The + tendinous fibres by which some Bivalves are as it were anchored or + moored to sub-marine substances. A fine example of this is to be seen + in the Pinnæ which bear some resemblance to large Muscle Shells and + have an hiatus in the margins of the valves through which a bunch of + silken fibres passes. In the British Museum there is preserved a pair + of gloves which have been woven of these fibres. The Byssus is peculiar + to some bivalve shells such as Muscles, Hammer Oysters, Arca Noæ, &c. + + CALCAR. Montf. (a spur.) A genus composed of TROCHUS STELLARIS, Lam. + and other depressed species of Trochus which are characterized by a + stellated keel round the angle of the last whorl; but not including T. + Imperialis, which is the genus Imperator, Montf. The difference + consists in the latter being umbilicated and the former not. T. + stellaris, fig. 358. + + CALCAREOUS, (_calx_, lime.) A term applied to a shell or to its + operculum which is composed principally of lime or shelly matter, as is + usually the case, in distinction from one which is of an horny, + membranaceous texture. The greater number of shells are calcareous, but + it forms an important point of distinction with regard to the + operculum. The only difference between the genera Trochus and Turbo, as + at present established, depends upon the calcareous or shelly, and the + corneus or horny texture of the operculum. + + CALCEOLA. _Fam._ Rudistes, Lam. and Bl.--_Descr._ Equilateral, + inequivalve, triangular; umbones separated by a large triangular disc + in the lower valve; cardinal margin straight, linear, dentated; lower + valve large, deep; upper valve flat, semi-orbicular, forming a kind of + operculum to the lower.--_Obs._ This singular shell, known only in a + fossil state, in the Palæozöic beds, is placed by Linnæus in the genus + Anomia. Lamarck places it among his Rudistes, but Mr. Sowerby in his + genera of Shells, states that it should be added to the family of + Brachiopoda. Fig. 194, 195. C. Sandalina. + + CALLANTICA. Gray. POLLICIPES hispidus, Leach. + + CALLIA. Gray? A genus described as having a peculiarly polished shell + like Pupina, but wanting the notch. + + CALLISOSTOMA. Sw. A genus of shells separated from TROCHUS, and thus + described, "Imperforate; spire elevated, acute; aperture broader than + high, transversely ovate, hardly sinuated at the base, and slightly + oblique; shells always smooth, and often polished." C. zizyphina is + mentioned as an example. + + CALLIRHOE. Montf. p. 362, vol. 2. Appears to be figured from the nut or + inner portion of a large Belemnite. + + CALLISCAPHA. Gray? IRIDINA Nilotica, Sow. Zool. Journ. 1. pl. 2. + Separated from Iridina on account of the hinge margin being smooth. + + CALLITHEA. Sw. A sub-genus of Mitræ, consisting of those species, which + like M. sanguisuga, have the "spire and aperture of nearly equal + length; internal channel nearly obsolete; shell with longitudinal + linear ribs, crossed by transverse striæ and bands; base contracted." + Swainson Mallac. Lard. Cyclop. + + CALLOSITY. A term used in general zoology to express those hard horny + tumidities formed in the skin of some animals, (such as the Dromedary, + for instance) in those parts which are most frequently used. It is not + used in this sense by Conchologists, who apply it to those undefined + tumidities or bumps which appear on the inner surface and hinge of some + bivalve shells, and to the thickening over the umbilicus of Naticæ. + Glycimeris, fig. 67. Natica, fig. 327, 328. + + CALPURNUS. Montf. OVULUM _verrucosum_, Auct. Distinguished by the small + circular tubercle at the back of each extremity of the shell. Fig. 441. + + CALYPTRACEA. Lam. A family belonging to the first section of the order + Gasteropoda, Lam., the shells of which are described as always + external, covering the animal, and having no operculum. The genera + contained in this family may be thus distinguished. + + 1. CALYPTRÆA. Conical; apex central, septum spiral, cup-shaped, or + forked; including _Infundibulum_. Fig. 234 to 238. + + 2. CREPIDULA. Apex terminal; septum flat, reaching half across the + aperture. Fig. 239. + + 3. CAPULUS. Conical; apex obliquely curved, no septum. Fig. 240. + + 4. EMARGINULA. Apex curved backwards; a notch in the anterior + margin; including _Parmophorus_. Fig. 241, 242. + + 5. CEMORIA. A slit _near_ the apex. Fig. 244. + + 6. FISSURELLA. A slit _upon_ the apex. Fig. 245. + + 7. RIMULA. A slit near the margin. Fig. 243. + + 8. ANCYLUS. Apex curved sidewise. Fig. 246. + + CALYPTRACEA. Bl. The second family of the order Scutibranchiata. Bl. + thus described: "Shell more or less conical, not spiral, or very + slightly so; aperture large and entire." The genera included in this + family are Crepidula, Calyptræa, Capulus, Hipponyx, and Notrêma. + + CALYPTRÆA. Lam. _Fam._ Calyptracea, Lam. and Bl.--_Descr._ Conical, + patelliform, irregular, with an internal, lateral, salient plate or + septum, varying in form.--_Obs._ The internal appendage is in some + species cup-shaped, in some it juts out of the centre in a double + point; in others it is only a small flap; and in others a spiral disc. + These last, which are shaped like Trochus, are separated by De Montfort + under the appellation INFUNDIBULUM; TROCHATELLA, Sw. The Calyptræa may + be known from Crepidula by the septum, which in the latter is a flat + plate reaching half way across the cavity. Fig. 234, 5, 6. + + CAMERINA. Brug. NUMMULITES, Auct. + + CAMILLUS. Montf. A genus founded upon a minute spiral shell, with a + triangular aperture, turned over the back of the last whorl. It is + figured in Soldani's Testacea Microscopica. + + CAMPULOTUS. Guettard. MAGILUS, Auct. + + CANAL. A groove which characterizes some spiral univalves, where the + inner and outer lips unite at the front part of the aperture. This + canal is drawn out in some shells to a considerable length, in others + it is turned abruptly over the back. The family Canaliferæ, Lam. (fig. + 372 to 401), are all provided with this canal. + + CANALICULATED. Applied generally to any distinct groove or canal. + + CANALIFERA. (_Canalifères_, Lam.) A family belonging to the order + Trachelipoda, Lam. nearly corresponding with the family Entomostomata + in De Blainville's system, and described as having a canal of greater + or less extent at the anterior part of the aperture. This canal is + sometimes straight, sometimes tortuous, and in some genera it is + recurved over the back of the shell. All the shells have an operculum, + and the thickness of the perfectly formed outer lip does not increase + with age. The Canalifera are characterized by having a canal, in + distinction from the Purpurifera, which have only a notch. This family + contains the following genera, + + 1. CERITHIUM. Club-shaped. Fig. 372. + + 2. POTAMIS. The same, fresh water. Fig. 377. + + 3. NERINEA. The same, with internal folds. Fig. 374. + + 4. TRIPHORA. Anterior and posterior canals closed so as to present + three openings. Fig. 375, 376. + + 5. TELESCOPIUM. Pyramidal, trochiform. Fig. 378. + + 6. PLEUROTOMA. A slit on the upper part of the outer lip; including + _Clavatula_. Fig. 379, 381. + + 7. TURBINELLA. Three horizontal folds on the columella. Fig. 382, + 383. + + 8. SPIRILLUS. Spire papillary; one fold on the columella. Fig. 384. + + 9. CANCELLARIA. Three folds, and internal costæ. Fig. 385. + + 10. FASCIOLARIA. Oblique folds, the lowest the largest. Fig. 386. + + 11. FUSUS. Fusiform; no folds on the columella. Fig. 387. + + 12. PYRULA. Pear-shaped. Fig. 388 to 390. + + 13. STRUTHIOLARIA. Outer lip thickened; sinuated. Fig. 391. + + 14. RANELLA. Two rows of varices; a canal at each extremity of the + aperture. Fig. 393, 394. + + 15. MUREX. Three or more rows of varices; only one distinct canal. + Fig. 395, 396. + + 16. TYPHIS. A tubular perforation between each varix. Fig. 397. + + 17. TRITON. Varices not in rows. Fig. 398 to 401. + + CANCELLARIA. Auct. (From _Cancellatus_, cross-barred, like window + frames or net work.) _Fam._ Canalifera, Lam. Entomostomata, Bl.--Descr. + Oval, thick, cancellated; spire generally short, pointed; aperture + sub-ovate, emarginated anteriorly, pointed at the posterior extremity; + outer lip marked within by transverse ridges; inner lip spread over + part of the body whorl, terminating in a straight, thick, obtuse + columella, with several strong oblique folds. _Hab._ Indian Ocean, + Coast of Africa, America, and West Indies. Fossils found in London Clay + and Calc-grossier of Paris. Differing from Turbinellus in form and in + the transversely ribbed inside of the outer lip. Fig. 315. C. + reticulata.--_Obs._ The latest enumeration of the species of this genus + is contained in a catalogue published by Mr. G. B. Sowerby, senior, + accompanying the author's figures of the new species, amounting to 38, + in parts 9 to 13 of the Conchological Illustrations. The greater part + of these new species were brought to this country by Mr. Cuming. + + CANCELLATED. (From _Cancellatus_, cross-barred.) Applied generally to + any shells which are marked by ridges crossing each other as + Cancellaria, fig. 385. + + CANCILLA. Sw. A sub-genus of Mitræ, described as having "the whorls + crossed by transverse linear ribs; inner canal wanting, plates very + oblique; form slender; outer lip thin." _Ex._ M. Isabella, M. sulcata. + + CANCRIS. Montf. CREPIDULINA, Bl. A genus of microscopic Foraminifera. + + CANOPUS. Montf. A genus of microscopic Foraminifera. + + CANTHAPLEURA. Guild. A genus composed of those species of Chiton, which + have the mantle rough, with moveable spines, prickles, or hairs. _Ex._ + C. spinosus, fig. 227. + + CANTHARIDUS. Montf. TROCHUS IRIS, Auct. and analogous species. + Elenchus, Humph. + + CANTHARUS. Montf. A genus of microscopic Foraminifera. + + CANTHIDOMUS. Sw. A sub-genus of Melanopsis, thus described: "spire + generally short; whorls coronated with spines, or marked with + longitudinal ribs; base obtuse. C. costata, Sow. Gen. f. 3." Melanopsis + costata, plates, fig. 315. + + CANTHORBIS. Sw. A sub-genus of the sub-family Trochinæ, Sw. Described + as being "nearly disc-shaped: spire but slightly raised; the margin of + the body-whorl flattened, and serrated with flat spines; inner lip + united to the outer; pillar and aperture as in the last. (Tubicanthus.) + C. imperialis. Mart. 173. f. 1714." This sub-genus appears to include + those species of which De Montfort's genera Imperator and Calcar are + formed. + + CANTHROPES. Montf. Described as resembling a Nautilus, with the whorls + increasing so gradually, that the dorsal edge of the aperture advances + but little beyond the last whorl. This genus is not mentioned by + Blainville or Lamarck. + + CAPITULUM. Klein. POLLICIPES Mitellus, Lam. fig. 37*. + + CAPRELLA. ----? PLEKOCHEILUS, Guild. AURICULA Caprella, Lam. + + CAPRINA. D'Orb. DICERAS. Auct.? + + CAPRINUS. Montf. (Conch. Syst. t. 2. p. 143.) The figure appears to be + intended to represent Helix Nux-denticulata. + + CAPSA. Brug. _Fam._ Nymphacea, Lam.--_Descr._ Equivalve transverse, + subequilateral, subtrigonal; cardinal teeth, two in one valve, one + notched in the other; lateral teeth remote, obsolete; an external + ligament; two muscular impressions in each valve; a large sinus in the + muscular impression of the mantle.--_Obs._ This genus is so nearly + related to Donax, that it is difficult to distinguish it at first + sight. The Capsæ, however, have not the short, plain, straight, + posterior side, the distinct lateral teeth, nor the crenulated margins + which characterize nearly all the Donaces. They are found in the + British Channel, Brazil, and coast of Pacific Ocean. They are known + from Erycina by not having the pit in the hinge for the ligament. Fig. + 109. C. Braziliensis. + + CAPULUS. Montf. _Fam._ Calyptracea, Lam.--_Descr._ Obliquely conical, + posteriorly recurved; apex pointed, sub-spiral; aperture large, + rounded, oval; with two muscular impressions, lateral, meeting behind; + epidermis horny, rather velvetty. Britain, Mediterranean, West Indies, + California, Australia. + + CARDIACEA. (Cardiacées, Lam.) A family of the order Conchifera + Dimyaria, Lam. Most of the genera of shells contained in this family + are included in the very extensive family of Conchacea, in the system + of De Blainville. They are described as having irregularly formed + cardinal teeth, generally accompanied by one or two elongated lateral + teeth. Most of the species are ventricose, and have regular radiating + ribs. This family contains the genera Cardium, Cardita, Cypricardia, + Hiatella, Isocardia, and others enumerated in the explanation of + figures 122 to 130. Their characters may be thus explained. + + 1. CARDIUM. Two cardinal and two lateral teeth in each valve, + including _Hemicardium_, _Papyridea_ and _Aphrodita_, in the last + of which the teeth are nearly obsolete. Fig. 122, 123, 123*, 123**. + + 2. VENERICARDIA. Two oblique cardinal teeth, one elongated; + including _Cardita_, which has the umbones nearly terminal. + _Pachymya_ may probably be included, but the hinge is not known. + Fig. 121, 124, and 130. + + 3. HIPPOPODIUM. One elongated cardinal tooth. Fig. 129. + + 4. MEGALODON. Hinge broad, septiform, with a large tooth in the + centre of one valve. Fig. 127. + + 5. ISOCARDIA. Teeth laminar; umbones spiral. Fig. 126. + + 6. CARDILIA. The same, with a septiform posterior laminar tooth. + + 7. HIPPAGUS. Shaped like Isocardia, without teeth. Fig. 128. + + CARDILIA. Desh. _Fam._ Cardiacea, Lam. A genus formed for the reception + of Isocardia semi-sulcata, Lam. and a small fossil shell, which + Deshayes had formerly named Hemi-cyclonosta Michelini; thus described, + (translation) "shell oval, oblong, longitudinal, white, heart-shaped, + ventricose, with large prominent umbones; hinge with a small cardinal + tooth and a pit at the side; a spoon-shaped projection for the + reception of the internal ligament; anterior muscular impression + rounded, not deep; the posterior being upon a thin, horizontal lamina, + projecting in the anterior." Deshayes further remarks that although the + animal is unknown, the relations of the genus may be established by + means of the shell alone. Two families contain all the shells which + have the internal ligament inserted in a spoon-shaped projection; in + the one, that of the Anatinæ, the ligament is supported upon a little + bone, which is not soldered to the hinge; in the other, that of the + Mactraceæ, this little bone has no existence. In the former, all the + shells are inequivalve; in the latter equivalve. And M. Deshayes, + considering that the valves are equal, and that there is no separate + bone to the hinge, is of opinion that the genus ought to be placed near + the Lutrariæ, and not far from the Anatinæ. C. semisulcata, fig. 501, + 2. + + CARDINAL MARGIN. The edge of a bivalve shell on which the teeth is + placed. + + CARDINAL TEETH. The teeth upon the hinge directly beneath the umbones + of a bivalve shell, as distinguished from the lateral teeth, which are + placed at a distance on each side. In Venus, fig. 119, the cardinal + teeth, are marked by the letter c. + + CARDIOCARDITES. Bl. A genus separated from CARDITA, Auct. Thus + described (translation) "oval species, with the inferior margin nearly + straight, or a very little inflated, crenulated and completely closed. + _Ex._ La C. Ajar, Adans Seneg. pl. 16. fig. 2." + + CARDISSA. _Sw._ A genus composed of those species of CARDIUM _Auct._ + which are heart-shaped. _Ex._ C. dionæum, fig. 122. And C. Cardissa. + + CARDITA. Brug. _Fam._ Cardiacea, _Lam._ Submytilacea, Bl.--_Descr._ + Equivalve, inequilateral, ovate, subquadrate or oblong, marked + externally by ribs radiating from the umbones and terminating in a + crenulated margin on the inner surface; cardinal teeth in one valve, + one long, thick, oblique; another short, more straight; in the other + valve one long, oblique, thick. Muscular impressions two in each valve, + rather oval; palleal impression not sinuated.--_Obs._ This description + includes Lamarck's genus Venericardia, which, although consisting of + the more oblong species, is not considered sufficiently distinct to + justify the separation. Cypricardia is distinguished from this genus by + a remote lateral tooth. Mediterranean, Africa, East Indies, &c. Cardita + calyculata, fig. 124. + + CARDIUM. Auct. _Fam._ Cardiacea, Lam. Conchacea, Bl.--_Descr._ + Equivalve, sub-equilateral, sometimes gaping posteriorly, ornamented on + the outside by ribs radiating from the umbones; cardinal teeth, two in + each valve, locked into each other crosswise, lateral teeth, two in + each valve, remote; muscular impressions, two in each valve; palleal + impression entire. Ligament external, inflated.--_Obs._ Although this + genus includes many remarkable forms, the characters are so easily + defined that there is no difficulty in distinguishing it from any other + genus. C. angulatum, fig. 123. C. Groenlandicum, fig. 123*. APHRODITA, + Lea. C. Hemicardium, fig. 123**. fig. 122. C. Dionæum. It is somewhat + surprising that this genus, which contains some of the most beautiful + forms of bivalve Testacea, should have been left till quite lately + without any attempt to revise the species and settle the synonyms. The + author of this Manual has endeavoured to remedy this defect by + publishing a catalogue of all the species hitherto known, which amount + to 97, including many new species described by him in the "Proceedings + of the Zoological Society," in 1840. Parts 46 to 51, 149 and 150, and + 177 to 184 of his Conchological Illustrations contain figures of 60 + species. Cardia are frequent in all climates. + + CARINARIA. Auct. _Class_, Cephalopoda. _Division_, Monothalamia, Lam. + _Fam._ Nectopoda, Bl.--_Descr._ Symmetrical or nearly so, conical, + thin, glassy, fragile, patelliform; with a fimbriated dorsal keel; apex + convolute, bent forwards; aperture oval, pointed at the dorsal + extremity. _Hab._ Amboyna, Indian Ocean, and Mediterranean Sea.--_Obs._ + A most singular and beautiful shell, remarkable for its transparency, + its fragile structure, and the dorsal keel, whence it derives its name. + It was once so rare that a single specimen was known to realize one + hundred guineas. Fig. 488. C. Mediterranea. + + CARINATED. (From _Carina_, a keel.) Applied to any shell having a + raised, thin ledge, passing round a whorl or any other part of a shell, + as in Carinaria, fig. 488. + + CARINEA. Sw. A genus formed for the reception of OVULUM gibbosum, Auct. + and similar species, fig. 443. + + CARINELLA. Adanson. LUTRARIA papyracea, Lam. LIGULA, Leach. _Fam._ + Mactracea, Lam. Fig. 77. + + CARINIDEA. Sw. A sub-genus of the genus Canthorbis, Sw. (Turbo.) thus + described, "Imperforate; spire pyramidal, acute; basal whorl concave + beneath, and carinated round its circumference; aperture oval, entire, + slightly angulated at the base of the pillar, which turns inwards. C. + concavus, Martini, 168, fig. 1620, brevispinosus? Sow. Gen. (Turbo,) + fig. 1." + + CAROCOLLA. Auct. _Fam._ Colimacea, Lam.--_Descr._ Orbicular, depressed, + with the outer sides of the whorls angulated or keeled, whorls few; + peritreme reflected; columella contiguous to the axis; epidermis + thin.--_Obs._ This genus differing from Helix only in the whorls being + angulated, is hardly distinct enough from the latter to justify the + separation. In De Ferrusac's system these species constitute the + division Helicigona, of the genus Helix. C. Lamarckii, fig. 277. East + and West Indies, Philippines, South America and Europe. + + CARTILAGE. See LIGAMENT. + + CARYCHIUM. Müll. _Fam._ Auriculacea, Bl. Colimacea, Lam.--_Descr._ + Oblong or cylindrical, with gradually increasing whorls, few in number; + aperture straight, short, with a fold on the columella.--_Obs._ This + genus of minute land shells differs from Auricula chiefly in the soft + parts. De Furrusac enumerates three species, C. Lineatum, C. + Corticaria, (_Odostomia_, Flem.) and C. Minimum, fig. 301. De + Blainville places it in his genus Auricula, as "species with two folds + and a posterior tooth on the columella," giving a figure of A. Mysotis + as his example, and quoting the name Phitia, Gray. Europe. + + CASSIDARIA. Lam. (From Cassis) _Fam._ Purpurifera, Lam. Entomostomata, + Bl.--_Descr._ Oval, ventricose, spirally grooved and tuberculated, with + a short turrited spire and a large aperture, terminating anteriorly in + a recurved canal; outer lip thickened, reflected, undulated or + denticulated; inner lip expanded over a part of the body whorl and the + columella, with part of its lower edge free.--_Obs._ The recent species + of this genus are not numerous; the few fossil species occur in the + tertiary strata. C. carinata is found in Calc-grossier and London Clay. + In general form this resembles CASSIS, but is at once distinguished by + the canal, which does not turn abruptly back, but is slightly curved + upwards. ONISCIA (C. Oniscus, &c. Lam.) is distinguished by the + shortness of the canal, and the granulated surface of the inner lip. + Fig. 407. C. Echinophora. Mediterranean. + + CASSIDEA. Sw. (from Cassis.) A genus composed of those species of the + genus CASSIS, Auct. which have the "aperture wide; outer lip never + broad or flattened, but sometimes slightly inflected; inner lip + spreading, but never dilated or detached beyond the base into a + prominent rim." East Indies. Ex. C. Glauca, fig. 411. + + CASSIDULA. Humph. PYRULA, Auct. + + CASSIDULINA. D'Orbigny. A genus of microscopic Foraminifera. + + CASSIS. (A helmet.) _Fam._ Purpurifera, Lam. Entomostomata, + Bl.--_Descr._ Oval or triangular, ventricose, thick, generally + tuberculated, with a short varicose spire; aperture long, sometimes + narrow, with the outer lip thickened and reflected, generally + denticulated; the inner lip spread over the surface of the body whorl, + indented and incrassated at its inner edge; canal turned suddenly over + the back of the shell. _Hab._ Seas of tropical climates. The fossil + species are rare, occurring in the tertiary strata.--_Obs._ The large, + common species of this well known genus are used for shell cameos and + as ornaments on chimney pieces, grottos, &c. and are remarkable for the + triangular disc, presented by the inner lip, which, in many species, is + thickened and spread over the front of the body whorl and the angulated + outer lip. The smaller, more rounded species, which have widened + apertures, have been separated by Swainson, under the generic name + CASSIDEA. The C. rufa, coarctata, &c. are formed by Mr. Stutchbury into + a new genus under the name CYPRÆCASSIS, for reasons which will be + stated under the word. Cassidaria is distinguished by the gradual curve + of the canal. Fig. 410 is Cassis tuberosa, diminished. + + CASTALIA. Lam. _Fam._ Trigonées, Lam.--_Descr._ Fluviatile, equivalve, + inequilateral, trigonal, with corroded umbones; hinge with two laminar, + transversely striated teeth, one of which is posterior, remote from the + umbones, short, divided, the other anterior, elongated; epidermis + thick; internal surface pearly. Lamarck, in describing this shell, + states, that he regards it as intermediate between Trigonia and Unio. + It should, however, certainly have been placed in the family of + "Nayades," and perhaps should form a part of the genus UNIO itself. C. + ambigua, Lam. fig. 140. South America. + + CATILLUS. Brong. (A little dish.) INOCERAMUS, Sow. + + CATOPHRAGMUS. Sow. (From [Greek: Katô], _beneath_; [Greek: phragmos] _a + place_ _paled in_.) _Order_, Sessile Cirripedes, Lam.--_Descr._ Light + principal valves, cemented side by side in a circle; eight small + pointed valves beneath, covering the joints of the upper circle, and + numerous still smaller valves forming the base of the shell; operculum, + four valves.--_Obs._ This is the only genus of Sessile Cirripedes, + consisting of eight principal valves, excepting Octomeris, which is + destitute of the accessary pieces from which the genus derives its + name. Fig. 23. C. imbricatus. South Africa. + + CAUDAL CANAL. The elongated hollow process which terminates the + aperture anteriorly of some univalve shells. For instance, Murex + Haustellum, fig. 396, has an elongated caudal canal. + + CELLANTHUS. Montf. VORTICIALIS, Bl. A genus of microscopic + Foraminifera. + + CELLULACEA. Bl. The second order of Cephalophora, Bl. consisting of + doubtful microscopic bodies, with a number of variously arranged + shells, as distinguished from the true Polythalamia, Bl. or chambered + shells. See FORAMINIFERA. + + CEMORIA. Flemingii. Leach. A small patelliform shell, differing from + Fissurella, in having the fissure placed behind the apex, which is + produced, pointed and incurved. It is the Patella Fissurella, Müll. + Patella Noachina, Chemn. F. Noachina, Sow. Puncturella, Lowe. Fig. 244. + Cemoria Flemingii. Scotland and Tierra del Fuego. + + CENTRAL. A term used to indicate the position of the muscular + impression of a bivalve shell when it is near the centre of the inner + surface. It is also applied to the siphon perforating the septum of a + chambered shell when it is placed near the centre of the plate. + _Sub_-central is also used as a comparative term, to indicate the + position of the siphon, or of the muscular impression, is _near_ the + centre. Thus in Placuna (fig. 184), the muscular impression is central: + in Exogyra (fig. 183), it is _sub_-central. + + CEPA. Humph. ANOMIA, Linn. + + CEPHALOPHORA. Bl. The first class of Malacozoæ, Bl. Divided into: + _Order_ 1. Cryptodibranchiata; 2. Cellulacea; 3. Polythalamacea. The + first consisting of Cuttle-fish, &c. which are destitute of shells; the + second composed of those microscopic cellular bodies, which are + regarded as shells by some authors; and the third containing the true + chambered shells. + + CEPHALOPODA. Lam. (Cephalopodes.) ([Greek: Kephalê], _kephale_, head; + [Greek: pous], [Greek: podos], _podos_, foot.) The fourth order of the + _class_ Mollusca, Lam. containing molluscs, which are characterized by + having a series of arms surrounding the head, which is placed above a + sack-shaped body. This order is divided into Polythalamia, or + many-chambered shells; Monothalamia, or single-chambered cephalopods; + and Sepiaria, or cuttle-fish. Fig. 463 to 488. + + CEPOLIS. Montf. Belonging to the genus HELIX, Auct. + + CERATODES. Guild. ([Greek: Keratôdês], like a horn.) A genus composed + of the flat, orbicular species of AMPULLARIA, Auct. which present so + near a resemblance to the Planorbes, as to have been considered as + belonging to them. Planorbis has, however, a horny texture, and no + operculum, and it is always reversed, which may be observed by placing + the spire upwards. Fig. 320, represents Ampullaria (Ceratodes) + Cornu-arietis. + + CERIPHASIA. Sw. A sub-genus of Melanianæ, thus described, "Cerithiform; + outer lip thin, dilated at the base; aperture small, slightly + emarginate, without any internal groove; inner lip thin. C. sulcata, + Sw. fig. 38. p. 204." (Sw. Lard. Cyclop. Malac. p. 342.) + + CERITHIUM. Brug. _Fam._ Canalifera, Lam. Entomostomata, Bl.--_Desc._ + Elongated, ribbed, tuberculated, or rarely smooth, with a lengthened, + turrited, pointed, pyramidal spire, consisting of numerous whorls; + aperture sub-quadrate, terminated anteriorly by a tortuous canal; outer + lip thickened, sometimes reflected, expanded; inner lip thickened + posteriorly; operculum horny, spiral, with numerous whorls.--_Obs._ The + fresh-water shells described as Cerithia by Lamarck, are separated + under the name Potamis, and may be known by the thick, horny epidermis. + Triphora, Desh. has the canal closed, except at the extremities. + Cerithium Telescopium, does not appear to present the same characters + as the other Cerithia, and has been separated by some writers under the + generic name Telescopium. Cerithium Aluco, fig. 372. Mediterranean, + East and West Indies, Coasts of the Pacific, Gallapagos, Australia, &c. + Some small species are British. Fossils are numerous in the tertiary + beds. + + CERVICOBRANCHIATA. Bl. The second order of Paracephalophora + Hermaphrodita, Bl. containing symmetrical patelliform shells, divided + into the families Retifera and Branchifera. + + CETOCIS. Montf. _Fam._ Orthocerata, Lam. and Bl. Placed by De + Blainville in his section of Belemnites, characterized as having small + folds at the apex. _Ex._ B. Penicillatus. + + CETOPIRUS. Ranz. CORONULA BALÆNARIS, Auct. fig. 16. + + CHAMA. Auct. _Fam._ Chamacea, Lam. and Bl.--_Descr._ Inequivalve, + irregular, thick, foliaceous, attached by the umbo of the lower and + larger valve. External ligament placed in a groove, following the curve + of the umbones. Umbones spiral, coiled round on the back of the valves; + hinge with a thick, crenated, lengthened tooth, in one valve, entering + a corresponding cavity in the hinge margin of the other; muscular + impressions, two in each valve, distinct, lateral.--_Obs._ The Linnæan + genus Chama, included the beautiful shells now called Tridacna. These + are exceedingly different from the true Chama, being regular and + unattached. The Chama (Tridacna) gigas, when at its full age and + development, is the largest shell known. Specimens have occurred + weighing upwards of 500 lbs., and measuring two feet across. Diceras + may be known from Chama by the spiral horns into which the umbones are + produced; Isocardia, by the regularity of the shells, and it is hardly + necessary to mention Spondylus, which may be known by the triangular + disc between the umbones; Cleidothærus, Stutch. which resembles Chama + in general form, has a separate bony appendage attached to the hinge, + and may, moreover, be distinguished by its elongated muscular + impression. Fig. 153, C. Lazarus. E. and W. Indies. + + CHAMACEA. Bl. The seventh family of the order Lamellibranchiata, Bl. + containing the genera Chama, Diceras, Etheria, Tridacna, Isocardia and + Trigonia. + + CHAMACEA. Lam. A family belonging to the order Conchifera Dimyaria, + Lam. described as inequivalve, attached, irregular; with or without a + single rough tooth on the hinge; with two lateral muscular impressions + in each valve. This family contains the genera-- + + 1. CHAMA. Leafy; umbones spiral. Fig. 153. + + 2. ETHERIA. Very irregular, pearly, without teeth. Fig. 155. + + 3. DICERAS. Like Chama, but the umbones free, produced. Fig. 154. + + CHAMBERED. When the cavity of a shell is not continuous, but is divided + by shelly diaphragms or septa, it is said to be chambered. This is the + case with the shells of the Polythalamous Cephalopoda, as in the + Nautilus (see Introduction). The character is not confined to these, as + it occurs in some species of Spondyli, and in several turrited + univalves. + + CHAMOSTRÆA. De Roissy. CLEIDOTHÆRUS. Stutch. + + CHARYBS. Montf. A genus of microscopic Foraminifera. + + CHELIBS. Montf. A genus of microscopic Foraminifera. + + CHELINOTUS. Sw. A genus of "HALIOTIDÆ," Sw. including Velutina, Lam. a + species of Sigaretus from Tonga, and Coriocella, Bl. Thus described, + "Animal cheloniform, broad; depressed; the mantle larger than the + shell, lobed in front; tentacula two, short, obtuse; eyes basal; mouth + circular; shell ear-shaped, thin, fragile, imperforate; pillar none." + + CHELONOBIA. Leach. CORONULA Testudinaria, Auct. Fig. 15. + + CHERSINA. Humph. ACHATINA, Lam. + + CHICOREUS. Montf. A generic division of the genus MUREX, consisting of + such species as have three ramified varices. _Ex._ M. inflatus, fig. + 395. + + CHILINA. Gray. _Fam._ Auriculacea, Bl. Colimacea, Lam.--_Descr._ Oval, + thin, covered with an olive green epidermis; spire rather short, + consisting of few whorls; aperture large, oval, rounded anteriorly; + outer lip thin, joining the inner lip without a sinus; inner lip spread + over part of the body whorl, terminating in a thick columella with one + or two folds.--_Obs._ These shells differ from the true Auriculæ in the + thinness of the outer lip. C. Dombeyana (Auricula Dombeyana, Auct.) + Fig. 300. The illustrated catalogue published by the author (Sow. + Conch. illustr. parts 135, 136) contains 13 species. Rivers of South + America. + + CHILOTREMA. Leach. A sub-genus of HELIX, containing Helix lapicida, + Auct. Gray, Turton, p. 140. + + CHIMOTREMA. ----? Belongs to HELIX. + + CHIONE. Megerle. CYTHERÆA maculosa, (fig. 117, c.) sulcata, circinata, + &c. Auct. and other similar species. + + CHIRONA. Gray. A genus of Balanidæ, the shells consisting of six + parietal valves and two opercular valves; the upper edges of the + parietal valves are sloped and the structure is not tubular. + + CHISMOBRANCHIATA. Bl. The second order of the first section of + Paracephalophora Monoica, Bl. Those Mollusca belonging to this order + which have shells, have them either internal or external, but always + scutiform, with depressed spires and wide, haliotoid, oblique + apertures, without a columellar lip properly so called. This order + partly answers to the family MACROSTOMATA, in the system of Lamarck. It + contains the genera Coriocella, Sigaretus, Cryptostoma, Oxinoe, + Stomatella and Velutina. + + CHITON. Auct. ([Greek: chiton], an integument.) _Fam._ Phyllidiana, + Lam. _Class_, Polyplaniphora, Bl.--_Descr._ Oval, consisting of eight + arched valves arranged in a series across the body of the animal and + fixed in the skin which forms a rim around them, sometimes scaly, + spinose, or rugose, sometimes smooth.--_Obs._ The genus Chiton, + commonly called "Coat of Mail," from its resemblance to jointed armour, + remains to the present day in exactly the same state with regard to its + boundaries as that in which Linnæus found it, and in which he left it. + That illustrious Naturalist placed it among the multivalves in his + purely Conchological system, although the animal is totally different + from the Cirripedes. The shells are prettily marked, and are found + attached to the rocks in all seas of Tropical and Southern climates, + but fossil species are almost unknown. Fig. 227, C. Spinosus. The genus + is divided by Guilding into Chiton, Canthopleura, Phakellopleura, + Chitonellus and Cryptoconchus. Zool. Journ. XVII. p. 27. The author of + this manual has lately attempted a revision of this interesting but + neglected genus, and has given a catalogue of all the species hitherto + known, as far as they could be identified among the confused mass of + synonyms and descriptions to be found in the works of various + Conchological writers. This catalogue is to be found in his + Conchological Illustrations, and refers to figures of 102 species, 92 + of which are contained in parts 38 to 45, and 159 to 176. + + CHITONELLUS. Lam. (From _Chiton_) Separated by Lamarck from Chiton, on + account of the valves being placed at a greater distance from each + other, the soft integument of the animal intervening. Fig. 228, C. + striatus. Philippines. + + CHLOROSTOMA. Sw. A sub-genus of "Trochinæ." Sw. (Trochus) of which C. + argyrostoma is given as an example. Sw. Lard. Cyclop. p. 350. + + CHONDRUS. Hartmann. ABIDA, Leach. A genus formed for the reception of + PUPA secale, Drap. Pupa Juniperi, Montague, which have plaits in the + aperture. + + CHRYSOAR. Montf. Probably a species of ORTHOCERAS. + + CHRYSODOMUS. Swains. "Distinguished from Fusus, by the comparative + shortness of the basal channel, and the ventricose or enlarged shape of + the body whorl. The beautiful orange-mouthed Whelk of England is a + typical example; and the few others now known are all of a very large + size, and chiefly found in Northern Seas, where they represent the more + elegant Fusi of tropical latitudes; the outer lip is always thin and + smooth." Sw. page 90, paragraph 78, described at page 308. + + CHRYSOLUS. Montf. POLYSTOMELLA, Bl. A genus of microscopic + Foraminifera. + + CHRYSOSTOMA. Sw. A genus of the family "Rotellinæ," Sw. Thus described + "Shell turbinate; the whorls few and convex; aperture effuse, round; + inner lip thickened just over, and almost concealing the umbilicus. + Nicobaricus, Martini, 182 fig. 1822-5." Sw. Lard. Cyclop. Malac. p. + 327. + + CHTHALAMUS. Ranz. _Fam._ Balanidea, Bl. Order, Sessile Cirripedes, + Lam.--_Descr._ "Shell much depressed, valves thick, thickened at the + base, with prominent areas; operculum nearly horizontal, composed of + four valves."--_Obs._ This description would apply generically to the + shell called Platylepas in the British Museum, only nothing is said + about the prominent plates jutting from the internal surface of the + valves. The difference between this genus and BALANUS consists + principally in the horizontal position of the operculum, and general + flatness of the shell. C. stellatus, fig. 18. + + CIBICIDES. Montf. A genus of microscopic Foraminifera. + + CIDARIS. Swains. A genus composed of TURBO Smaragdus, petholatus, and + other similar species. The word Cidaris is, however, already in use for + a genus of Echinæ. + + CIDAROLLUS. Montf. A genus of microscopic Foraminifera. + + CILIATED. (ciliæ, hairs.) Having minute hairs as in Orbicula, Lingula, + &c. and the jointed feelers of the Cirripedes. + + CIMBER. Montf. NAVICELLA, Auct. + + CINERAS. Leach. (_Cinereus_, ash-coloured.) _Order_, Pedunculated + Cirripedes, Lam.--_Descr._ Animal with a quadrilateral body, supported + on a fleshy peduncle, with an opening in front of the upper part for + the passage of a bunch of ciliated tentacula. Immediately above this + aperture is a pair of small elongated valves, placed in a nearly + horizontal position; at the lower part is another tripartite pair + placed perpendicularly, one on each side, and a narrow, angulated, + keel-shaped piece placed at the back.--_Obs._ The nearest approach to + this genus is Otion. (C. Vittatus, fig. 42.) Found upon substances + floating in the sea. + + CINEREOUS. (_Cinereus_) Ash-coloured. + + CINGULA. Fleming. RISSOA, Leach. + + CIONELLA. Jeffreys. _Fam._ Colimacea, Lam.--_Descr._ Oblong or + elongated; last whorl large; apex rather acute; columella, + sub-interrupted; aperture canaliculated, sub-effuse at the base; + margins very unequal; no umbilicus. BULINUS octonus, lubricus, acicula, + &c. Auct. C. lubrica, fig. 285. + + CIRCE. Schum. VENUS castrensis, fig. 117 d. V. sulcatina, arabica, + pectinata, Auct. and other similar species. + + CIRRIPEDES. Lam. The tenth class of invertebrated animals, so named + from the curled and ciliated branchia which protrude from the oval + aperture of the shells. The class Cirripedes of Lamarck constitutes the + entire genus _Lepas_ of Linnæus. They are divided into two sections; + first, Sessile Cirr. attached by the basal portion of the shell; + second, Pedunculated Cirr. supported upon a Peduncle. Figs. 14 to 45. + + CIRROBRANCHIATA. Bl. The first order of Paracephalophora Hermaphrodita, + Bl. This order has been formed for the purpose of giving a place in the + system to the genus Dentalium. The animal of which has lungs, + consisting of numerous filaments, having their basal origin in two + radical lobes under the neck. + + CIRRUS. J. Sowerby (cirrus, a tendril.) _Fam._ Turbinacea, Bl. and + Lam.--_Descr._ Spiral, conical, with a hollow axis; whorls contiguous, + numerous, rounded, or slightly angulated.--_Obs._ This fossil genus + resembles Trochus, from which it is known by the deep funnel-shaped + umbilicus. Fig. 349, C. nodosus. + + CISTULA. Humph. CYCLOSTOMA, Lam. + + CLANCULUS. Montf. TROCHUS _Pharaonis_, Lam.--_Obs._ This, with several + other species, belong more properly to MONODONTA, Lam. ODONTIS, Sow. + Fig. 361. + + CLATHODON. Conrad. GNATHODON, Gray. + + CLAUSILIA. Drap. (_Clausium_, a valve or folding door.) _Fam._ + Colimacea, Lam. Limacinea, Bl.--_Descr._ Spire elongated, consisting of + many volutions; aperture small, sub quadrate, having several + tooth-shaped folds on the columella. A small, elastic, shelly plate, + attached to the columella within, called the Clausium, its office being + to enclose the aperture when the animal has retired within the + shell.--_Obs._ This last character distinguishes it from the Pupæ, to + some of which it bears a very near resemblance. _Hab._ Land, in the + central and southern parts of Europe, several British species. Fig. + 295, C. Macascarensis. + + CLAUSIUM. A name applied to the beautiful contrivance whence the genus + Clausilia derives its name, consisting of a little bony tortuous plate, + placed in a groove on the columella. Here it serves the purpose of a + door, which, when not prevented by counteracting pressure, springs + forward on its elastic ligament, and encloses the animal in his + retirement. The aperture is opened by pushing back the clausium into + the groove. + + CLAUSULUS. Montf. Conch. Syst. 1, 179. A genus of microscopic + Foraminifera. + + CLAVA. Humph. CERITHIUM, Lam. + + CLAVAGELLA. Lam. (_Clava_, a club.) _Fam._ Tubicolæ, Lam. Pyloridea, + Bl.--_Descr._ Two irregular flattish valves, one fixed or soldered, so + as to form part of the side of an irregular shelly tube; the other free + within the tube near the base.--_Obs._ The shells composing this genus + are found in stones, madrepores, &c. and appear to form the connecting + link between Aspergillum, which has both valves cemented into the tube; + and Fistulana, in which both are free. Fig. 45, a fossil Clavagella. + Found recent on the Coast of Malta and New South Wales. + + CLAVALITHES. Sw. A genus composed of some fossil shells, separated from + the genus Fusus, which, having the general form of Turbinella Rapa, &c. + are considered by Swainson, as holding an intermediate station between + Fusus and the Turbinellidæ.--_Descr._ "Unequally sub-fusiform; the body + whorl, and spire, being conic; and the canal suddenly contracted and + attenuated; terminal whorls papillary; inner lip thick; pillar smooth, + C. longævus, clavellatus, Noæ, ponderosus, Sw."--_Obs._ The papillary + spire may form a sufficient reason for separating this genus from + Fusus, while the absence of plates on the columella places them at a + still greater distance from Turbinella. + + CLAVATE. When one extremity of the shell is attenuated, and the other + becomes suddenly ventricose or globular, it is said to be Clavate. + _Ex._ Murex Haustellum, fig. 396. + + CLAVATULA. Lam. The generic name by which Lamarck originally + distinguished those species of Pleurotoma which were remarkable for the + shortness of their canals. In his system, however, they are re-united + to Pleurotoma. Fig. 381, P. Strombiformis. + + CLAVICANTHA. Sw. A genus separated from Pleurotoma, Lam. consisting of + species, which are described as "thick, sub-fusiform; the surface + rugose, and the whorls sub-coronated; channel short; slit assuming the + form of a short, broad sinus. C. imperialis, E. M. 440, spirata, E. M. + 440, fig. 5, conica, E. M. 439, fig. 9, echinata, E. M. 439, fig. 8, + Auriculifera, E. M. 439, fig. 10." + + CLAVICLE. (_clavis_, a key.) A little key. This term is applied to the + bony appendage in the hinge of some species of Anatina, (those included + in the generic term Lyonsia) Cleidothærus, Myochama, &c. + + CLAVULINA. D'Orb. A genus of microscopic Foraminifera. + + CLAVUS. Montf. A genus of microscopic Foraminifera. + + CLEIDOTHÆRUS. Hutch. ([Greek: Thairos], hinge, [Greek: Kleis], + clavicle.) _Fam._ Chamaceæ or Myariæ, Lam.--_Descr._ Inequivalve, + irregular, solid, attached; with one cardinal, conical tooth in the + free valve, entering a corresponding indenture in the other; and an + oblong shelly appendage, fixed by an internal cartilage in a groove + under the umbones; muscular impressions, two in each valve, one + elongated, the other uniform.--_Obs._ This shell is like Chama in + general form, but is distinguished by the clavicle or shelly appendage + from which its name is derived. Fig. 75. New South Wales. + + CLEODORA. _Per. et Les. Fam._ Pteropoda, Lam. Thecosomata, + Bl.--_Descr._ Thin, transparent, pyramidal, with flat alate sides, and + oval aperture. Fig. 221, C. cuspidata. + + CLISIPHONITES. Montf. Microscopic. LENTICULINA, Bl. + + CLITHON. Montf. NERITINA Corona, spinosa, &c. Auct. fig. 325. + + CLITIA. Leach. _Fam._ Balanidea, Bl. _Order_, Sessile Cirripedes, + Lam.--_Descr._ Sub-conical, compressed, consisting of four unequal + valves, two larger and two smaller, joined together side by side, by + the interlocking of their dentated edges, a process somewhat like that + which joiners call dove-tailing. Operculum, consisting of two unequal + pointed valves.--_Obs._ Clitia is known from Creusia, by the + articulations of the valves, and by the operculum, which in Creusia + consists of four valves. Fig. 20. C. Verruca, (Lepas Verruca, Gmelin.) + Britain and Peru. + + CLOSE. The margins of a bivalve shell are described as being close, + when there is no hiatus between them in any part, otherwise they are + described as _gaping_. + + CLOTHO. Faujas. _Fam._ Conchacea, Bl. More properly belonging to the + Pyloridea, Bl.; and the Lithophagidæ, Lam.--_Descr._ "Oval, nearly + regular, longitudinally striated, equivalve, sub-equilateral; hinge + consisting of a bifid tooth, curved like a crochet, larger in one valve + than in the other." This description is translated from Blainville, who + states that he has never seen the shell. Annales du Museum D'Histoire + Naturelle, tom. 9, pl. 17, fig. 4-6. + + CLYPEIFORM. (_Clypeus_, a shield.) Open, flat, shaped like a shield or + buckler, as Umbrella, fig. 233, and Parmophorus, fig. 242. + + CLYPIDELLA. Sw. A sub-genus of Fissurella, described as having one + extremity of the shell slightly raised. C. pustula. Sow. Gen. fig. 3. + + COAT OF MAIL. A common name given to shells of the genus Chiton, on + account of their resemblance to jointed armour. + + COBRESIA. Hübner. VITRINA, Auct. + + COCHLIATE. (_Cochleare_, a spoon). Applied to any shell or part which + is hollow and oval, as Patellæ, &c. The cavity containing the cartilage + in Mya, fig. 71, is Cochleate. + + COCHLICELLA. One of the sub-genera into which De Ferrusac has divided + the genus Helix, consisting of Bulinus decollatus, fig. 279, and + similar species. See Helix. + + COCHLICOPA. Fer. A sub-genus of Helix, partly corresponding with + Polyphemus of De Montfort, and consisting of species of Achatina, which + have the outer lip undulated. + + COCHLITOMA. Fer. A sub-genus of Helix, corresponding with the genus + Achatina, Auct. not including those with undulated outer lips. + + COCHLODINA. Fer. A sub-genus of Helix, including the genus Clausilia, + Auct. + + COCHLODONTA. Fer. A sub-genus of Helix, containing Pupa Uva, Auct. &c. + + COCHLOGENA. Fer. A sub-genus of Helix, containing pupiform shells, such + as Azeca tridens, fig. 290. + + COCHLOHYDRA. Fer. A sub-genus of Helix, composed of the genus Succinea, + Auct. + + COCHLOSTYLA. Fer. A sub-genus of Helix, composed of the genus Bulinus, + Auct. + + COLIMACEA. Lam. This Family, of the order Trachelipoda, Lam. includes + all land shells, which might with propriety be divided into three + sections, the first of which contain the following well-known genera:-- + + 1. SUCCINEA. Oval, transparent, oblique; animal amphibious. Fig. + 265, 266. + + 2. HELIX. The type of which is the common snail shell. The + separation of _Carocolla_, on account of the angulated whorls, or + that of _Geotrochus_, on account of the turbinated shape, cannot be + well maintained. Fig. 264, 267, 268, 273 to 276, 278 to 281, 294. + + 3. ANOSTOMA. The aperture turned up towards the spire. Fig. 271, + 272. + + 4. STREPTAXIS. Whorls excentric. Fig. 269, 270. + + 5. BULINUS. Oval; aperture entire, including _Bulimulus_, _Balea_, + _Cionella_, _Azeca_. Fig. 282 to 285, 289, 290, 296. + + 6. ACHATINA. A notch terminating the columella. Fig. 286 to 288. + + 7. PUPA. Cylindrical; including _Vertigo_, _Alæa_, &c. Fig. 291 to + 293. + + 8. CLAUSILIA. Cylindrical, with a clausium. Fig. 295. + + _Obs._ The above are united in the system of De Ferrusac under the + generic name Helix, and divided into sub-genera as explained under + that word. + + The next section, included in the family Auriculacea, Bl., contains + the genera Auricula, Chilina, Carychium, Marinula, Scarabæus, and + Partula. Fig. 297 to 302. + + The third section contains the following genera of land shells with + opercula. + + 1. CYCLOSTOMA. Aperture round; operculum spiral. Fig. 303, 304. + + 2. NEMATURA. Last whorl contracted; operculum spiral. Fig. 305. + + 3. HELICINA. Aperture semi-lunar or angulated; operculum + concentric. Fig. 306, 307. + + 4. PUPINA. Shell polished; operculum concentric; aperture round. + Fig. 524. + + 5. STROPHOSTOMA. Aperture turned up towards the spire, like + Anostoma, but said to have an operculum. Only known fossil. Fig. + 97. + + COLUMBELLA. Auct. (Columba, a dove.) _Fam._ Columellata, Lam.--_Descr._ + Thick, oval, or angular; with short spire, and long narrow aperture, + contracted in the centre, and terminating in a short canal; outer lip + thickened and dentated; inner lip irregularly crenated. Epidermis thin, + brown. Operculum very small, horny.--_Obs._ Those species of Mitra, + which resemble Columbella in shape, may easily be distinguished by the + plaits on the columella. The Columbellæ are marine, and few fossil + species are known. Fig. 430, C. Mercatoria. Swainson has divided this + genus into the following: _Columbella_, consisting of C. Mercatoria, + &c.; _Pusiostoma_, consisting of the Strombiform species; + _Crassispira_, which is most probably a Cerithium; _Nitidella_, + consisting of the smooth species; _Conidea_, consisting of the more + conical species; another set of the more conical species has been + removed from this family, and placed in that of the "Coninæ," but as + they are separated by no essential character, we suppose this has + merely been done for the purpose of completing the "circle" of the last + mentioned family, which otherwise would not have reached the required + number of five. Mediterranean, East and West Indies, South America, + Coast of California, Gallapagos, &c. + + COLUMELLA. A solid column formed by the inner sides of the volutions of + a spiral univalve. It is sometimes described as the inner lip of the + aperture, of which it forms a part; but the term would be more properly + confined to that portion of the inner lip which is seen below the body + whorl, over which the remainder of the lip is frequently spread. All + the inner edge of the aperture, including that part of it which covers + the body whorl, is called the columellar lip. In fig. 431, the anterior + termination of the columella is indicated by the letter c. The axis, is + an imaginary line drawn strictly through the centre of the whorls, + whether their inner edges form a solid column or not. + + COLUMELLAR LIP. The inner lip. See COLUMELLA. + + COLUMELLATA. Lam. A family of the order Trachelipoda, Lam. containing + the following genera:-- + + 1. MITRA. Elongated; aperture narrow; strong folds on the + columella; including _Mitrella_, _Mitreola_, _Tiara_, and + _Conohelix_. Fig. 431, 432. + + 2. MARGINELLA. Outer lip reflected; including _Volutella_, + _Persicula_, _Gibberula_, and _Glabella_. Fig. 437. + + 3. COLUMBELLA. Outer and inner lips denticulated or granulated. + Fig. 430. + + 4. VOLUTA. Outer lip thickened; folds on the columella; aperture + generally wide; apex papillary; including _Scaphella_, _Harpula_, + _Volutilithes_, _Cymbiola_. Fig. 433, 436. + + 5. MELO. Shell comparatively light; spire short, sometimes hidden; + apex round, spiral; folds on the columella laminar. Fig. 435. + + 6. CYMBA. Upper edge of the aperture separated from the body whorl + by a flat disc; apex mammillated, irregular; folds on the + columella. Fig. 434. + + 7. VOLVARIA. Cylindrical; aperture long, narrow; folds on the + columella; spire hidden. Fig. 439. + + COLUS. Humphrey. FUSUS, Lam. + + COMPLANARIA. Sw. A subgenus of ALASMODON (Unio), thus described, "shell + winged; the valves connate; the bosses very small and depressed; + cardinal teeth two or three; lateral teeth represented by irregular + grooves. C. gigas (Unio), Sow. Man. fig. 141. Alasmodon complanatus, + Say. C. rugosa, Sw." + + COMPRESSED. Pressed together, or flattened. The application is the same + as in common use. A Patella may be described as a vertically compressed + cone. A Ranella, on account of the two rows of varices skirting the + whorls, appears, as it were, laterally compressed. A bivalve shell is + said to be compressed when it is flat, that is, when but a small cavity + is left in the deepest part when the valves are closed. Perhaps the + Placuna placenta, fig. 184, is the most remarkable instance of this. + + CONCAMERATIONS. (_Con_, with, _camera_, a chamber.) A series of + Chambers joining each other, as in Nautilus, Spirula, &c. + + CONCENTRIC. A term applied to the direction taken by the lines of + growth in spiral and other shells, (_longitudinal_ of some authors.) + Every fresh layer of shelly matter forms a new circle round an + imaginary line, drawn through the centre of the spiral cone, down from + the nucleus. When the edges of the successive layers are marked by any + external characters, the shell is said to be concentrically striated, + banded, grooved, costated, &c. A fine illustration of the latter is to + be seen in the Scalaria or Wentletrap, fig. 351, Lines, bands, ribs, + &c. in the opposite direction, (_transverse_ of some authors,) are + "radiating" in bivalves, as the ribs of Cardium, fig. 123, and "spiral" + in univalves, that is, following the direction of the whorls, as the + bands of colour in Pyramidella, fig. 342. + + CONCHACEA. Bl. The eighth family of the order Lamellibranchiata, Bl. + The shells are described as follows: nearly always regular, valves + closed all round; apices curved towards the anterior; dorsal hinge + complete, with teeth and ligament; the latter external or internal, + short and thick; two distinct muscular impressions, united at the lower + part by a parallel impression, which is frequently sinuated at the + posterior. The genera described in this family are divided into three + sections. First, those which are regular, and have distant lateral + teeth, Cardium, Donax, Tellina, Lucina, Cyclas, Cyprina, Mactra, and + Erycina. Second, those which are regular, and have no distant lateral + teeth, Crassatella and Venus. Third, those which are irregular, + Venerupis, Coralliophaga, Clotho, Corbula, Sphænia, and Ungulina. + + CONCHACEA. Lam. A family of Lamarck's order Conchifera Dimyaria. + Regular, unattached in general, closed at the sides. They are always + more or less inequilateral. The _Marine_ Conchacea are those which + inhabit the sea. The fluviatile Conchacea are those which are found in + rivers, ponds, &c. Each of these contain various genera, which may be + arranged as follows:-- + + _Fluviatile._ + + 1. CYRENELLA. Three cardinal teeth; ligament long; shell thin. Fig. + 114. + + 2. CYCLAS. Thin, oval; cardinal and lateral teeth; anterior side + shortest, including _Pera_. + + 3. PISIDIUM. The same, with the posterior side shortest. Fig. 112. + + 4. CYRENA. Thick; cardinal and lateral teeth. Fig. 113. + + 5. POTAMOPHILA. Two thick cardinal teeth. Fig 115. + + _Marine._ + + 1. CYPRINA. Two cardinal teeth, and one remote lateral tooth. Fig. + 116. + + 2. VENUS. Three cardinal, no lateral teeth; including _Artemis_. + Fig. 118, 119, 119a. + + 3. CYTHEREA. Several cardinal teeth; one very short lateral tooth. + Fig. 117, 117_a_, 117_b_, 117_c_, 117d. + + 4. PULLASTRA. Cardinal teeth notched, otherwise like Venus. Fig. + 120. + + 5. ASTARTE. Three cardinal teeth; ligament short. Fig. 110. + + VENERICARDIA belongs to the Cardiacea. + + CONCHIFERA. Lam. The 11th class of Invertebrata, consisting of all + those animals which have bivalve shells. Lamarck divides the class into + Dimyaria, which have two adductor muscles; and Monomyaria, which have + but one. + + CONCHOLEPAS. Montf. (CONCHA, a shell; lepas, a stone or rock.) _Fam._ + Purpurifera, Lam. Entomostomata, Bl.--_Descr._ Oval, imbricated, thick; + with a very short spire and large oval patelliform aperture, + terminating anteriorly in a slight emargination; outer lip crenated, + with two produced points or teeth towards the anterior, inner lip + smooth, nearly flat, reflected over the last whorl, so as nearly or + entirely to cover it; operculum horny. Marine, only one species known, + from Peru.--_Obs._ This shell is placed near Patella by Lamarck, on + account of its large open aperture; but having a horny operculum, and + resembling Purpurea in other respects. Fig. 418. Concholepas Peruviana. + + CONCHOTRYA. Gray. (_Concha_, a shell; [Greek: Truo], (_tryo_) to bore.) + _Order_, Pedunculated Cirripedes, Lam.--_Descr._ Five pieces, two pairs + ventral, one single; shaped like Pentelasmis. Found in holes. + + CONCHYLIOMORPHITE. A term used by De Blainville to designate the cast + or model of a fossil shell, formed by a siliceous substance which has + entered or surrounded it when in a liquid state, and subsequently + become hardened into flint. The shell has afterwards decomposed or + fallen off by accident, leaving its external or internal characters to + be conjectured from the monumental impressions that remain. + + CONCHYTA. Hupsch Mus. CALCEOLA, Lam. + + CONE. A common name for shells of the genus Conus. + + CONE. This mathematical term is used by conchologists in its utmost + latitude of signification to express a body, which in its formation, + commences in a small point, called the apex, and increases in width + towards the conclusion or base. It is applied to all shells, whether + the increase in width be gradual or sudden; or whether in its growth, + it takes a straight, oblique, curved, or spirally-twisted course. In + this sense, a bivalve would be described as a pair of rapidly + enlarging, oblique cones, and the aperture of every spiral shell would + be its base. But this phraseology being in disuse, it is only mentioned + here that it may be understood when occasionally met with. + + CONELLA. Sw. A genus composed of species of the genus Columbella, Lam. + which have a conical form, and which, on that account, are considered + by Swainson as belonging to his family of Coninæ. Swains. Lardner. + Cyclop. Malac. described at p. 312. C. picata, Sw. fig. 17, a. p. 151. + + CONFLUENT. A term applied to two parts of a shell when they gradually + flow into each other, as, for instance, the inner and outer lips of + Univalves when they pass into each other at the anterior extremity, + without the intervention of a notch or angle. + + CONIA. Leach. _Fam._ Balanidea. _Order_, Sessile Cirripedes, + Lam.--_Descr._ Four rather irregular valves, of porous structure, + placed side by side, so as to form a circular cone, supported at the + base on a shelly plate, and closed at the aperture by an operculum + consisting of four valves in pairs. Distinguished from Creusia by its + porous structure and by its flat support; that of Creusia being + cup-shaped. Fig. 21, Conia porosa. + + CONICAL. A term applied in the ordinary sense, and not as explained + above, under the word CONE. + + CONIDEA. Sw. A genus separated from Columbella, Lam. thus described, + "Mitra shaped, fusiform; spire equal or longer than the aperture; the + whorls tumid; outer lip slightly gibbous above, contracted below; + margin not inflected; striated within; inner lip terminating in an + elevated ridge, but with the teeth obsolete. C. semipunctata, + (_Columbella_, Lam.) Mart. 44. fig. 465, 466." Africa. + + CONILITES. _Fam._ Orthocerata, Lam. & Bl.--_Descr._ "Conical, straight + or slightly curved; having a thin external covering, independent of the + nut or alveole, which it contains. Alveole transversely chambered, + sub-separable." (Translated from Lam.)--_Obs._ The difference between + Belemnites and Conilites is that the external sheath of the latter is + thin, and not filled up with solid matter, from the point of the + alveole to the apex, as in the former. De Blainville places in this + genus the genera Thalamulus, Achelois and Antimomus, Montf. two of + which are figured, Knor. Sup. Fab. iv. fig. 1. 1. 8. 9. Conilites + Pyramidatus, fig. 470. + + CONILITHES. Sw. A sub-genus of Coronaxis, Sw. (Coni, with coronated + whorls) thus described, "Conic; spire considerably elevated; the + aperture linear, C. antediluvianus, Sow. Gen. f. 1." + + CONOHELIX. Sw. (_Conus and Helix._) The generic name given to those + species of Mitra which are conical in form. Fig. 432, C. marmorata. + + CONOPLÆA. Say. _Order_, Sessile Cirripedes, Lam. A genus composed of + Balani, attached to the stems of Gorgonia, having their bases + elongated. _Ex._ fig. 27, Balanus Galeatus. + + CONORBIS. Sw. A genus composed of species of CONUS, such as C. + dormitor, (Sowerby, gen. fig. 8) which have elevated spires and the + upper part of the outer lip deeply sinuated. Mr. Swainson considers + these fossil species as analogous to the Pleurotomæ. _Sw._ Lard. + Cyclop. Malac. p. 312. + + CONOVULUM. A genus proposed by Lamarck, to include the small, conical + species of Auricula, which have the outer lip simple. This genus was + afterwards abandoned by the author. _Ex._ fig. 298, Auricula + coniformis. + + CONTIGUOUS. (_Contingo_, to touch.) A term applied to the whorls of + spiral shells when they rest upon, or touch each other. This is the + case in a great majority of instances. When, on the contrary, there is + a space between the whorls, they are said to be non-contiguous, + detached, or free. Examples of non-contiguous whorls are to be seen in + Scalaria, fig. 351 (in this case, the distance between the whorls is + small), and in Crioceratites, fig. 482. A "_Columella contiguous to the + axis_," is when in the centre of the shell and takes the place of the + imaginary line which forms its axis. + + CONTINUOUS. Carried on without interruption, as the siphon in Spirula, + the varices in Ranella, fig. 394, which, occurring in a corresponding + part of each whorl, form a continuous ridge. + + CONULARIA. Miller. A genus of Orthocerata, described as conical, + straight, or nearly so, divided into chambers by imperforate septa; + aperture half closed; apex solid, obtuse; external surface finely + striated. Resembling Orthoceras, but wanting the siphon. Fig. 449. + + CONUS. Auct. ([Greek: Kônos], a cone.) _Fam._ Enroulées, Lam. + Angyostomata, Bl.--_Descr._ Conical, convolute, with a short spire, + consisting of numerous whorls; and narrow lengthened aperture, + terminating in a slight emargination at each extremity; outer lip thin; + epidermis thin; operculum small, pointed, horny.--_Obs._ This + well-known genus of shells is easily distinguished from any other, by + its conical form, its smooth columella, its narrow aperture, and thin + outer lip. The form of the spire varies from flat and even partially + concave, to a regular pyramidal cone; and the upper edges of the whorls + are rounded in some species, angulated in others, and in some are waved + or coronated. The variety of marking and the numerous delicate tints of + these shells have caused them to be highly appreciated by amateur + collectors; and many species, as the C. Ammiralis, or admiral; the C. + Gloria Maris, or Glory of the Sea; the C. Cedonulli ("I yield to + none"), and others, have always produced good prices in the markets. We + give figures of the principal forms, as expressed in the genera + proposed by De Montfort, of Rhombus, Hermes, Rollus and Cylinder, in + figures 459 to 462. Many new species were brought to this country by + Mr. Cuming, and are represented in parts 24, 25, 28, 29; 32, 33, 36, + 37; 54, 55, 56, 57; 147, 148; 151 to 158 of the Conchological + Illustrations, by G. B. Sowerby, jun. See CORONAXIS, Swainson. The + cones are mostly tropical, some are found as far north as the + Mediterranean, and south as the Cape of Good Hope. The most beautiful + species are from the East and West Indies. + + CONVOLUTÆ. (Enroulées, Lam.) A family of the 2nd section of the order + Trachelipoda, Lam. the genera of which may be distinguished as + follows:-- + + 1. CYPRÆA. Lips thickened, inflected, with teeth; spire hidden, + including _Cypræovulum_, _Luponia_, _Trivia_. Fig. 444 to 450. + + 2. OVULUM. Lips thickened, inflected, with slight crenulations; + spire hidden. Fig. 440 to 443. + + 3. ERATO. Lips thickened, inflected; spire visible; a groove down + the back. Fig. 454. + + 4. TEREBELLUM. Cylindrical, open at the anterior extremity; + columella smooth; suture of the spire canaliculated. Fig. 451, 452. + + 5. OLIVA. Columella plaited, swelled into a varix at the anterior. + Fig. 457, 458. + + 6. ANCILLARIA. The same, but the suture of the spire covered with + enamel. Fig. 455, 456. + + 7. CONUS. Turbinated, numerous whorls; spire flat or short, + conical; columella smooth. Fig 459 to 462. + + CONVOLUTE. (_Con_, together; _volvo_, to revolve). This term can be + strictly applied only to symmetrical shells, signifying that the + volutions are parallel to each other in a horizontal direction, as in + the Ammonites, &c.; but the term is also commonly used in describing + such shells as Conus, in which, the direction of the whorls being + scarcely oblique, the last whorl almost entirely covers those which + precede it. This is the case with Lamarck's family of Enroulées. Fig. + 440 to 462. + + CORALLIOPHAGA. Bl. CYPRICARDIA Coralliophaga, Lam.--_Descr._ Oval, + elongated, finely striated from the apex to the base, cylindrical, + equivalve, very inequilateral; umbones slightly raised and quite + anterior; hinge nearly the same in both valves; two small cardinal + teeth, one of which is bifid, placed before a kind of lammellated + tooth, beneath a very slender external ligament; two small, distant, + muscular impressions, united by a striated palleal impression, which is + strongly striated posteriorly.--_Obs._ This shell, which is found in + the empty holes of dead Lithodomi, in some instances conforming its + shape to its situation, differs from Cypricardia of Lamarck, + principally in its cylindrical form. C. Carditoidea, fig. 92. + Mediterranean and East Indies. + + CORBICULA. Megerle. CYRENA, Lam. + + CORBIS. Cuv. (_A basket._) _Fam._ Nymphacea, Lam.--_Descr._ Transverse, + oval, thick, ventricose, equivalve, sub-equilateral, free, cancellated, + with denticulated internal margins; hinge with two cardinal and two + lateral teeth in each valve; of the latter, one near and one remote + from the umbones; muscular impressions lunulate, two in each valve, + united by an entire palleal impression, without a sinus.--_Obs._ This + genus, of which only two or three recent species are known, resembles + many species of Venus and Cytherea in general form; but differs in + having lateral teeth, and in the palleal impressions which in all the + Veneres, &c. is sinuated. From Lucina it may be known, not only by its + oval form, but also by the muscular impressions, which, in Lucina are + produced into an elongated point; it will also be distinguished from + Tellina, by the want of a posterior fold in the valve, for which that + genus is remarkable. C. Fimbriata, fig. 101, is an inhabitant of the + Indian Ocean. Several fossil species are found in the recent + formations, above the chalk, at Grignon and Hauteville. + + CORBULA. Brug. (_A little basket._) _Fam._ Corbulacea, Lam. Conchacea, + Bl.--_Descr._ Inequivalve, sub-equilateral, transverse, gibbose, not + gaping; cardinal tooth in each valve, conical, curved, prominent, + inserting its extremity into a pit in the opposite hinge; cartilage + attached to the tooth of the smaller valve, and the pit in the larger; + muscular impressions, two in each valve, distant, rather irregular; + palleal impression posteriorly angulated.--_Obs._ The shells composing + this genus were placed in Mya by Linnæus, but differ from the true Myæ + in having a sinus in the palleal impression, and a prominent + ligamentiferous tooth in each valve, whereas the Myæ have but one. The + Corbulæ are marine, some species inhabiting the British coasts. Fossil + species occur abundantly in green sand, London clay, crag, and + corresponding formations. Fig. 89. C. Nucleus. + + CORBULACEA. (Corbulées, Lam.) A family of the order Conchifera + Dimyaria, Lam., containing the genera-- + + 1. CORBULA, with a prominent curved tooth. The Fresh-water species + has been separated under the name _Potamomya_. Fig. 89. + + 2. PANDORA. Thin, pearly, no teeth. Fig. 90. + + CORDIFORM. (_Cor_, a heart.) Heart-shaped, a term applied generally to + any shell which may be fancied to resemble a heart in shape, as + Isocardia, fig. 126, and Cardium Dionæum, fig. 122. + + CORIACEOUS. (_Corium_, leather.) Of the substance of leather. _Ex._, + the integument into which the valves of Chitones are inserted. + + CORIOCELLA. Bl. The animal designated by this name is described by De + Blainville as being without any traces of shell, either internal or + external. This must have arisen from the imperfection of the specimen + described, probably deprived by accident of its shell. The testaceous + appendage of the Coriocella is now well known to naturalists. It is a + milky white, transparent shell, shaped like Sigaretus. + + CORNEA, and PISUM, Megerle. CYCLAS, Lam. + + CORNEO-CALCAREOUS. A term used to express the mixture of horny and + shelly matter which enters into the composition of some shells, + Aplysia, for instance. It is also applied to those Opercula, which are + horny on one side, and testaceous on the other, as that of Turbo. + + CORNEUS. Horny. A species of Patella has had the specific name corneus + given to it, because its texture more nearly resembles that of a horn + than that of a shell. The epidermis of fresh-water shells is of a + similar composition. + + CORNUCOPIA. Humph. LEPAS, Linn. + + CORONALES. See CORONULAR MULTIVALVES. + + CORONATED. (_Corona_, a crown.) Applied to shells when ornamented with + a series of points, tubercles, &c., round the upper edges of the + volutions. _Ex._ Conus Nocturnus, fig. 459. + + CORONAXIS. One of the two genera into which Swainson divides the genus + Conus, consisting of those species which have a row of tubercles on the + upper edge of the whorls, an arrangement by which he would in many + instances, not only separate between two individuals of the same + species, but also between two parts of the same shell; for instances + occur in which the earlier whorls are coronated, while the body whorl + and the penultimate are perfectly plain. + + CORONULA. (_Corona_, a crown, dim.) _Order_, Sessile Cirripedes, Lam. + _Fam._ Balanidea, Bl.--_Descr._ Six radiated valves, joined side by + side in a circle, forming a depressed cone; internal structure of the + valves, porous or chambered; thickened at the base; operculum + consisting of four valves in pairs; imbedded horizontally in a + cartilaginous substance.--_Obs._ The shells composing this genus are + found partly imbedded in the skin of whales, and the shells of + tortoises, and are therefore destitute of the shelly foundation on + which the Balani and other Coronular Multivalves are supported. C. + Testudinaria, (CHELONOBIA, Leach,) fig. 15. C. Balænarum, (CETOPIRUS, + Ranz.) fig. 16. C. Diadema, (DIADEMA, Ranz.) fig. 17. + + CORONULAR MULTIVALVES are those which have their parietal valves joined + together side by side in a circle, surrounding the body of the animal, + so as to form a sort of coronet. This is the characteristic of the + Sessile Cirripedes of Lamarck's system, the Balanidea of De Blainville. + + CORRODED. (_Corrodo_, eat away, consume.) The umbones, apices, and + other thick parts of shells, are frequently worn away or consumed by + the action of the element in which they exist. As the thickest parts of + some shells are the most subject to this operation, it appears to the + author to arise from the outer surface of the shell, being less under + the influence of the animal juices than the other parts; and therefore, + more exposed to the influence of the surrounding element. This, + however, is not the case with respect to the Nayades and other + fresh-water shells; with these, corrosion does not take place until + after the thick epidermis which covers them, becomes wounded by some + means or other, and then the animal thickens its shell within as fast + as it is corroded without. + + CORTALUS. Montf. (Conch. Syst. 1. 115.) A genus of microscopic + Foraminifera, placed by De Blainville in a division of the genus + Rotalites. + + COSTATED. Ribbed, as Cardium Angulatum, fig. 123. + + COSTELLARIA. A sub-genus of the genus Tiara, Sw. (Mitra.) C. rigida. + Swainson, Zool. Ill. 1st series, pl. 29. + + COWRY. A common name for shells of the genus Cypræa. + + CRANIA. (_Cranium_, a skull.) _Fam._ Rudistes, Lam. _Order_, + Pallio-branchiata, Bl.--_Descr._ Inequivalve, equilateral, irregular, + sub-quadrate; upper valve patelliform, conical, with the umbo near the + centre; lower valve attached by its outer surface; muscular + impressions, 4 in each valve; two large, posterior, distant; two small, + near to each other, central. No hinge teeth; no ligament.--_Obs._ This + genus properly belongs to the Brachiopoda, Lam. It differs from + Orbicula in the mode of attachment, which in the latter, is by a byssus + passing through the lower valve, and not by the valve itself. Hipponyx + has only two muscular impressions in each valve. The name of this genus + is derived from the inner surface of the attached valve, which presents + a remarkable resemblance to the facial portion of a human skull. This + appearance is caused by the situation and elevated edges of the + muscular impressions. Fig. 197. Coasts of Britain and Mediterranean. + + CRASSATED. (_Crassus_, thick.) Used to express a thickness in the + substance of a shell. _Ex._ Glycimeris, fig. 67. + + CRASSATELLA. Lam. (_Crassus_, thick.) _Fam._ Mactracea, Lam. Conchacea, + Bl.--_Descr._ Equivalve, inequilateral, close, thick, rounded + anteriorly, rostrated posteriorly, with denticulated margins, smooth, + or ribbed transversely; hinge with a triangular pit containing the + cartilage, two anterior cardinal teeth, and a posterior depression in + one valve; one anterior tooth and a slight anterior marginal elevation, + and a posterior elevation in the other valve. Muscular impressions + distant, strongly marked. Palleal impression not sinuated.--_Obs._ The + few recent species known are marine, several being brought from the + coasts of New Holland. Fossil species are found in Calcaire-grossier + and London clay. The Crassatella are known from the Veneres, &c., by + the ligamentary pit in the hinge, and from Lutraria and Mactra by the + thickness and closeness of the shell. Fig. 84, C. rostrata. + + CRASSINA. Lam. ASTARTE, Sow. + + CRASSIPEDES. Lam. (_Crassus_, thick; _pes_, foot.) The first section of + the order Conchifera Dimyaria, Lam. In this section the foot of the + animal is thick, and the shell gapes considerably. It is divided into + the families Tubicolæ, Pholadidæ, Solenidæ, and Myaria. Fig. 44 to 76. + + CRASSISPIRA. Sw. A genus separated from COLUMBELLA, Auct. for which Mr. + Swainson quotes "Pleurotoma Bottæ, Auct." Crassispira fasciata, Sw. + Lardn. Cyclop. Malac. p. 313. + + CRENATED. (_Crena_, a notch.) Applied to small notches, not + sufficiently raised or defined, to be compared to teeth. _Ex._ The + hinge of Iridina, fig. 150. + + CRENATULA. Lam. _Fam._ Malleacea, Lam. Margaritacea, Bl.--_Descr._ + Compressed, foliated, irregular, sub-equivalve, inequilateral, oblique; + umbones terminal; hinge linear, nearly straight, with a series of + excavations, containing the cartilage, while the intervening ridges are + covered with the ligament, properly so called. Muscular impression + oblong, indistinct.--_Obs._ This genus is known from Perna by the + hinge, which in the latter is composed of a series of regular, + straight, ligamentary grooves placed across it. In Crenatula also there + is no passage for the byssus, as in Perna. C. Mytiloides, fig. 168. + Coasts of the Red Sea. + + CRENULATED. Finely crenated or notched. + + CREPIDULA. Lam. (_Crepidula_, a little slipper.) _Fam._ Calyptracea, + Lam. and Bl.--_Descr._ Oval, irregular, patelliform; apex lateral, + incurved, or sub-spiral; external surface convex, smooth, ribbed, + waved, or covered with spines; interior concave, smooth, with a + flattish septum reaching nearly half across the cavity; epidermis light + brown.--_Obs._ The difference between this genus and Calyptræa is that + in the latter, the septum is more free from the sides of the shell, so + that, instead of forming a regular plate, covering half the aperture, + it assumes a variety of shapes, and in some is cup-shaped, in others + forked, and in some forms a little angular shelf. Indeed, the + variations are so numerous that I think it would be better to throw the + two genera into one, and then divide them into smaller groups. Some + species of Calyptræa are farther removed from each other with respect + to the characters of the septum and general form of the shell, than + they are from the Crepidulæ. Fig. 239. Mediterranean, North and South + America, East and West Indies, New South Wales, &c. + + CREPIDULINA. Bl. CRISTELLARIA, Lam. Microscopic. + + CRESEIS. Ranz. _Order_, Pteropoda, Lam.--_Descr._ Thin, fragile, + transparent, pyramidal, pointed; with a dorsal ridge produced into a + point at the edge of the aperture.--_Obs._ The species found in the + Mediterranean is named C. Spinifera (fig. 222), from its resemblance to + a thorn. + + CREUSIA. Leach. (_Creux_, se. Fr. a cavity.) _Fam._ Balanidea, Bl. + _Order_, Sessile Cirripedes, Lam.--_Descr._ A depressed cone, + consisting of four valves, supported upon, and jointed to, a cup-shaped + cavity formed in the Madrepores, in which it resides. Aperture + quadrilateral, closed by an operculum of four valves.--_Obs._ This + genus is distinguished from Pyrgoma, which is supported on the edge of + a similar cup-shaped cavity, by the paries being composed of four + valves, whereas in Pyrgoma, it consists of a single piece. Fig. 28, C. + Gregaria. East Indies. + + CRICOSTOMATA. Bl. The second family of Asiphonibranchiata, Bl. It is + thus described: "shell equally (with the animal) variable in general + form, but of which the aperture, always nearly round, is completely + closed by the shelly or horny operculum; whorls few, and apex + sublateral." This family agrees in some measure with the family + Turbinacea of Lamarck, and with the genus Turbo in the system of + Linnæus. It contains the genera Pleurotomaria, Delphinula, Turritella, + Proto, Scalaria, Vermetus, Siliquaria, Magilus, Valvata, Cyclostoma, + and Paludina. + + CRIOCERATITES. A genus composed of species of Ammonites, with + disconnected whorls. C. Duvallii, fig. 482. + + CRIOPUS. Poli. CRANIA, Auct. + + CRISTACEA. Lam. The third family of Polythalamous Cephalopoda, Lam. + This family is described as including shells of the following + characters:--"Multilocular, flattened, nearly reniform; the chambers + gradually increasing in length, as they approach the outer arched + margin, and appearing to revolve round an eccentric, more or less + marginal axis. The Cristacea contain the genera Renulina, Cristellaria, + and Orbiculina." + + CRISTACEA. Bl. The third family of Polythalamia, Bl. containing the + genera Crepidulina, (Cristellaria, Lam.) Oreas and Linthuris. + + CRISTARIA. Schum. DIPSAS Plicatus, Leach. ANODON tuberculatus, Fer. + + CRISTELLARIA. Lam. CREPIDULINA, Bl. _Fam._ Cristacea, Lam. and + Bl.--_Descr._ Semidiscoidal, chambered; whorls contiguous, enlarging + progressively; spire eccentric, sublateral; septa imperforate. + Microscopic. + + CRYPTA. Humph. CREPIDULA, Lam. + + CRYPTELLA. Webb. ([Greek: Kruptô], to conceal.) TESTACELLUS Ambiguus of + Ferrusac. Published in Sowerby's Genera of Shells as PARMACELLA + calyculata.--_Descr._ A small patelliform shell, with a very short + papillary spire; and the aperture irregularly expanded. Fig. 256. + Canary Islands. + + CRYPTOCONCHUS. Bl. A genus composed of species of Chiton, the valves of + which are covered by the integument, as Chiton porosus of Burrows. Ch. + amiculatus of Pallas. + + CRYPTODIBRANCHIATA. Bl. The first order of the class Cephalophora, Bl. + containing families of molluscous animals destitute of shells. + + CRYPTOSTOMA. Bl. Differs from SIGARETUS, Lam. principally in the soft + parts of the animal. De Blainville remarks that he is acquainted with + only two species (from the Indies), which he can with decision refer to + the genus, but he thinks that many of the Lamarckian Sigareti may very + probably be found to belong to it, as soon as the soft parts shall be + known. The species which he figures is Cryptostoma Leachii. (Manuel de + Malacologie, pl. 42. fig. 3.) + + CTENOCONCHA. Gray. Described as having many characters in common with + the Solens, the teeth like Nucula, but the cartilage entirely external. + SOLENELLA, Sow.? + + CUCULLÆA. Lam. (_Cucullus_, a hood.) _Fam._ Arcacea, Lam.--_Descr._ + Sub-quadrate, nearly equivalve, sub-equilateral, deep; hinge + rectilinear, with a series of angular teeth, small near the umbones, + larger and more oblique towards the extremities; umbones separated by a + flat external area, on which the ligament is spread. Anterior muscular + impression produced into a sharp-edged plate or ledge, projecting from + the side of the shell. Posterior muscular impression flat and + indistinct.--_Obs._ This genus very much resembles Arca in general + form, but differs in the oblique, lengthened character of the remote + teeth, and in the singularly prominent edge of the muscular impression. + China. Fig. 133, C. Auriculifera. + + CUCUMIS. Klein. MARGINELLA, Auct. + + CULTELLUS. Species of LUTRARIA, Lam. which have the umbones placed near + the extremity of the shell. _Ex._ L. Solenoides, fig. 78. + + CUMA. Humph. FUSUS and FASCIOLARIA, Lam. + + CUMINGIA. Sow. _Fam._ Mactracea, Lam.--_Descr._ Equivalve, + inequilateral, transverse, rounded anteriorly, subrostrated + posteriorly. Hinge with a central spoon-shaped cavity in each valve, + containing the cartilage; a very small anterior cardinal tooth in each + valve; two lateral teeth in one valve, none in the other: muscular + impressions two in each valve, distant; palleal impression with a very + large posterior sinus.--_Obs._ The species known at present are found + in sand, in the fissures of rocks in Tropical climates. They resemble + Erycina in general form and character, but differ in having the + internal cartilage placed in a prominent spoon-shaped process, while + that of Erycina is contained in a hollow which sinks under the umbones. + This genus should be placed near Amphidesma. Cumingia mutica, fig. 87. + + CUNEIFORM. (_Cuneus_, a wedge.) Wedge-shaped, as Donax, fig. 108. + + CUNEUS. Megerle. VENUS Meroe, Linn. and similar species. + + CUNICULA. Sw. A sub-genus of Uniones, thus described:--"Ovate, oblong; + bosses thick, but depressed; cardinal teeth moderate. C. planulata, + patula, rubiginosa, secura, purpurascens." + + CURVED. Arched or bent. _Ex._ Dentalium, fig. 2. + + CURVULA. Rafinesque. A fossil imperfectly described as differing from + Pinna, in being inequivalve. + + CUVIERIA. Ranz. (Baron Cuvier.) _Class_, Pteropoda, Lam.--_Descr._ + Thin, transparent, glassy, cylindrical, rounded and inflated at the + closed extremity, compressed towards the opening, so as to render it + oval. This genus differs from Vaginula in being rounded, instead of + pointed, at the lower extremity. Mediterranean. Fig. 223, C. Columella. + + CYCLAS. Brug. _Fam._ Conques Fluviatiles, Lam. Conchacea, Bl.--_Descr._ + Orbicular, thin, subovate, ventricose, sub-equilateral, equivalve; + cardinal teeth minute, one more or less complicated in the left valve, + two diverging in the right; lateral teeth elongated, compressed, + laminar, acute, doubled in the left valve; ligament external; epidermis + thin, horny.--_Obs._ The Cyclades are viviparous, and abound in + ditches, ponds, slow streams, &c. in Europe and North America. The + genus Pisidium has been separated on account of a difference in the + animal, and may be known from Cyclas by being less equilateral, and the + anterior side being the longest. Fig. 111, C. Rivicola. + + CYCLOBRANCHIATA. Bl. The third order of the second section of + Paracephalophora Monoica, Bl. containing no genera of Testaceous + Mollusca. + + CYCLOCANTHA. Sw. A genus of "Trochidæ," consisting of Turbo stellaris + and T. Calcar, and corresponding with the genus Calcar, Montf. + + CYCLONASSA. Sw. A genus of "Nassinæ," Sw. consisting of Nassa + Neritoidea, and corresponding with the genus Cyclops, Montf. + + CYCLOPHORUS. Montf. A generic name proposed for those species of + Cyclostoma, Auct. which have an umbilicus. C. Involvulus, fig. 304, + would be the type of this genus. + + CYCLOPS. Montf. NASSA Neritoidea, Auct. fig. 424. + + CYCLOSTOMA. Auct. ([Greek: kuklos], _cyclos_, round; [Greek: stoma], + _stoma_, mouth.) _Fam._ Colimacea, Lam. Cricostomata, Bl. A genus of + land shells varying in shape from that of Pupa to that of a flat orb; + the aperture is generally circular and the peritreme uninterrupted, + thickened and sometimes reflected, the operculum is shelly and spiral. + Two other genera of land shells are provided with opercula, and + consequently might be confounded with this genus. In Helicina, the + operculum is concentric and the peritreme is not continuous; while in + the small genus hitherto almost unknown of Pupina, the peritreme is not + continuous and there is a glassy enamel over the whole of the external + surface. In the plates we have represented, C. ferrugineum, fig. 303; + C. involvulus, fig. 304. + + CYCLOTUS. Guild. A sub-genus of Cyclostoma, consisting of those species + which are discoidal, as C. Planorbulum. Fig. 530. + + CYLINDER. Montf. CONUS textile, Auct. (fig. 461) and other species + having a cylindrical form. + + CYLINDRELLA. Sw. A genus of the family "Ovulinæ," Sw. composed of + cylindrical species of Ovulum? The wood-cut illustrating this genus has + the appearance of a Bulla. + + CYLINDRICAL. ([Greek: kulindros], a cylinder.) This like other + mathematical terms is used with great latitude by Conchologists, and + applied to any shell the sides of which are nearly parallel, with the + extremities either rounded, flat, or conical. _Ex._ Oliva, fig. 457. + + CYLLENE. Gray. _Fam._ Purpurifera, Lam.--_Descr._ Oval, thick, with a + short acute spire; an oval aperture terminating anteriorly in a slight + emargination, posteriorly in a short canal; a fold at the lower end of + the body whorl; outer lip thick, striated within; angle of the whorls + tuberculated.--_Obs._ This genus of small marine shells resembles + Voluta in general character, but differs in having a smooth columella + without folds. Recent, Pacific Ocean; Fosil, London clay. Fig. 425. + + CYMBA. Brod. (_Cymba_, a boat or skiff.) _Fam._ Columellaria, + Lam.--_Descr._ Smooth, ventricose, with a very short, mammillated, rude + spire; and a very large, wide aperture, terminated anteriorly in a deep + emargination; posteriorly in a flat ledge, which separates the outer + lip from the body whorl; columella with three or four oblique, laminar, + projecting folds, terminating in a point; outer lip thin, with its edge + sharp; epidermis smooth, brown, covered partly or entirely by the + glassy enamel, which, commencing with the outer lip, spreads over the + body of the shell.--_Obs._ These very elegant shells, found in Africa, + are distinguished from the true Volutes by the shapeless, mammillated + apex of the short spire, by the large size of the aperture, and by the + horizontal ledge which separates the outer lip from the body whorl. The + genus Melo, also separated by Mr. Broderip from the Volutes, agrees + with Cymba in some respects, but differs in the regularity of the + spire. Fig. 434, C. Porcina. + + CYMBIOLA. Sw. The generic name for a group of Volutes, described as + "armed with spinous tubercules, sometimes smooth, but never ribbed; + spiral whorls gradually diminishing in size, but not distorted; apex + thick and obtuse; pillar with four plaits." Mr. Swainson remarks that + this genus is chiefly distinguished by the obtuse, but not irregular + spire. The typical species are stated to be V. Rutila and V. + Vespertilio, fig. 433. Tropical. + + CYMBULIA. (Dim. from _Cymba_.) _Fam._ Pteropoda, Lam. An extremely + light, cartilaginous covering of a molluscous animal, so named from its + similarity in shape to a boat. We mention it here on account of its + similarity to the shelly or glassy covering of other Pteropods, to + which, although membranaceous, it is evidently analogous. The Cymbuliæ + are found in the Mediterranean. + + CYPRÆA. Auct. _Fam._ Enroulées, Lam. Angyostomata, Bl.--_Descr._ Oval + or oblong, ventricose, convolute, covered by an enamel, generally + smooth and shining. Spire short, nearly hid. Aperture long, narrow, + terminating in a short canal at both extremities. Outer lip dentated, + thickened, inflected. Inner lip dentated, thickened, reflected over + part of the body whorl.--_Obs._ These shells are so distinguished by + the two rows of teeth arranged on each side of the aperture; the + thickened front formed by the inner and outer lips; and the enamel + deposited over the back of the shell from the mantle of the animal + which envelopes it, that there is no danger of confounding them with + any other genus, except in a young state. Before they have arrived at + the full growth, the front is not thickened, and the outer lip is thin, + not inflected, nor are the teeth formed. In this state the shell + resembles, in some degree, an Oliva. Some species are striated, ribbed, + or tuberculated, but the generality are smooth. Most species belong to + tropical climates, only one to Great Britain. The C. Moneta is current + as money in some parts of Africa, and many species are worn as + ornaments by the South Sea Islanders. The colouring in most species is + exceedingly rich, and arranged in every variety of spots, patches, + rings, lines, bands and clouds. The species most esteemed by collectors + are C. Mappa, C. Testudinaria, C. Pustulata, C. Aurora, C. Princeps, of + which only two specimens are known, C. Leucodon, &c. See also + Cypræovulum, Trivea and Luponia. The fossil species are principally + from the Calc-grossier, the London Clay, Crag, &c. Fig. 445 to 450. The + latest revision of this genus has been effected by Mr. G. B. Sowerby, + sen., who has published a complete catalogue in his son's Conchological + Illustrations. This catalogue enumerates 130 species, the whole of + which are figured in parts 1 to 8, 101 to 131 of the above mentioned + work. + + CYPRÆCASSIS. Stutch. (Cypræa and Cassis.)--_Descr._ Shell, when young, + striated, reticulated, or tuberculated; outer lip simple: when mature, + outer lip involute and toothed; columellar lip also toothed; aperture + straight, anteriorly terminated by a recurved canal, posteriorly by a + shallow channel. Animal with the mantle bilobed; operculum + none.--_Obs._ The reasons given for separating this genus from Cassis, + are, 1st, That the shells of the latter have an operculum, while those + of the proposed genus have none. 2nd, That the Cypræcassides do not + form a complete, thickened lip, before the full period of their growth, + like the Cassides. 3rd, That the Cypræcassides have no epidermis. The + species mentioned as probably belonging to Cypræcassis are C. rufa, the + type; C. coarctata, and C. Testiculus, Auct. The establishment of this + genus has been opposed on the ground that indications of epidermis are + discoverable in some specimens of C. rufa; that some specimens of the + same species and Testiculus have been examined, and found to have + formed slightly thickened and dentulated outer lips at very early + periods of growth, while many of the other Cassides are destitute of + varices, and that an operculum of C. coarctata was brought to this + country by Mr. Cuming. It is probable, however, that an increased + knowledge of facts might go far to establish the separation. C. + Testiculus, fig. 412. + + CYPRÆADIA. Sw. A genus of the family "Cypræidæ," Sw. thus + described:--"Cypræform; the base contracted; the body whorl not + flattened beneath; shell cancellated; aperture of equal breadth + throughout; a few thickened, short teeth on the pillar; lip at the + base, which is not internally concave. C. cancellata, Sw. Fossil only, + differing from Trivea in its contracted base, in the inequality of its + aperture, and the equal convexity of the inner lip within." (Sw. Lardn. + Cyclop. Malac. p. 325.) Cyprædia, fig. 564. + + CYPRÆLA. Sw. A genus formed for the reception of Ovulum verrucosum, + Auct. which has a circular depression at each extremity. It is the same + as the genus Calpurnus of De Montfort. Ovulum verrucosum, fig. 441. + + CYPRÆOVULUM. Gray. A genus of Cypræidæ thus described, "shell like a + cowry, but front end of columella covered with regular cross-ribs, like + the rest of the base, internally produced into an acute toothed ridge. + Shell pear-shaped, cross-ridged." C. capense, fig. 444. South Africa. + + CYPRICARDIA. Lam. _Fam._ Cardiacea, Lam.--_Descr._ Equivalve, + inequilateral, subquadrate, transversely elongated, with the anterior + side very short; hinge with three cardinal teeth and one remote lateral + tooth in each valve; muscular impressions two in each valve; ligament + external.--_Obs._ This genus is distinguished from Cardita by the three + cardinal teeth. The mollusca of this genus are marine. C. angulata, + fig. 125. Pacific Ocean. + + CYPRINA. Lam. _Fam._ "Conques Marines," or Marine Conchacea.--_Descr._ + Equivalve, inequilateral, sub-orbicular; umbones curved obliquely; + hinge with three diverging cardinal and one remote lateral teeth in + each valve; ligament external; muscular impressions two in each valve; + palleal impression having a slight posterior sinus; epidermis thick, + rough brown.--_Obs._ The Cyprinæ belong to the Northern hemisphere. The + recent species are not numerous. Fossil species are found in the + tertiary deposits. Cyprina may be known from Venus by the remote + lateral tooth and the thick epidermis. C. vulgaris, fig. 116. + + CYRENA. Auct. _Fam._ Fluviatile Conchaceæ, Lam. Conchacea, Bl--_Descr._ + Suborbicular, equivalve, inequilateral, ventricose, corroded at the + umbones, thick, covered with a thick epidermis; hinge with three + cardinal and two remote lateral teeth in each valve. Muscular + impressions two in each valve; palleal impression not sinuated.--_Obs._ + This genus is distinguished from Venus, Cytherea and Cyprina, by having + two remote lateral teeth; and from Cyclas by the thickness of the + shell. This genus is mostly fluviatile; the recent species are + tropical, and the fossil are found in the newest formations. Fig. 113, + C. fuscata. + + CYRENELLA. Desh. See CYRENOIDES. + + CYRENOIDES. Joannis. CYRENELLA, Desh. _Fam._ Conques Fluviatiles, + Lam.--_Descr._ Equivalve, subequilateral, ventricose, thin, covered + with a reddish brown epidermis, corroded at the umbones, with a slight + posterior fold. Hinge thin, with three diverging cardinal teeth in each + valve, and a very slight posterior fold in the right valve. Ligament + not very tumid.--_Obs._ This fresh-water shell differs from Cyclas and + Cyrena in the want of lateral teeth, and from the latter in the + thinness of the shell. Fig. 114. + + CYRTIA. Dalman. ([Greek: Kurtos], curtos, gibbose.) _Fam._ Brachiopoda, + Lam.--_Descr._ "Hinge rectilinear; with the back elevated into a + semicone or half-pyramid, the cardinal side perpendicularly + _plane_."--_Obs._ This genus of fossil Brachiopoda forms part of the + genus Spirifer, Sow. C. exporrecta, (Anomites exporrecta, Nonnull.) + fig. 204. + + CYTHEREA. Lam. _Fam._ "Conques Marines," Lam.--_Descr._ Equivalve, + inæquilateral, oval, lenticular, or sub-trigonal; hinge with two or + more short, diverging cardinal teeth, and one anterior approximate + lateral tooth in each valve.--_Obs._ The Cythereæ are distinguished + from the Veneres by the lateral tooth. C. Meretrix, fig. 117, and 117, + _a. b. c. d._ + + DACTYLUS. Humph. MARGINELLA, Auct. + + DARACIA. Gray. A subgenus of Pyrgoma, including a species which is + remarkable for the irregularity of its form. It grows upon a species of + Monticularia, and the margin takes the shape of the lobes by which it + is surrounded. The aperture is large, and completely closed by the + operculum. Daracia (Pyrgoma) Monticulariæ, fig. 489, 490. + + DATE. A common name given to shells of the genus Pholas, on account of + their cylindrical form and consequent resemblance to the fruit. For the + same reason the name Pholas Dactylus has been given by Naturalists to + the species which we represent, fig. 66. + + DEAD SHELL. A term used among collectors to signify that the shell has + been exposed on the sea-shore after the animal has ceased to live. A + shell in this condition is worn down by attrition, and loses its beauty + and brilliancy of colouring by being subject to the action of salt + water. A dead shell may be known by a certain hoary whiteness spread + over its surface. + + DECACERA. Bl. The second family of the order Cryptodibranchiata, Bl. + containing the genera Calmar and Sepia, which have no shells. + + DECADOPECTEN. Rüppell. PECTEN _Plica_, Linn. Fig. 172, having a + plicated hinge. + + DECOLLATED. (_Decollari_, to be beheaded.) The apex or nucleus of some + shells being composed of a more fragile substance than the rest, has a + tendency to fall off. The reason of this probably is that the animal + withdrawing from that part, leaves it unprotected. When it falls off, + the hole is stopped up by a septum filling the cavity of the volution, + so as to exclude the air: the shell is then said to be decollated. + _Ex._ Bulinus decollatus, fig. 289. + + DECUSSATED. Intersected by striæ crossing each other. _Ex._ Rissoa, + fig. 346. + + DELPHINULA. Montf. (_Delphinus_, a dolphin.) _Fam._ Scalariens, Lam. + Cricostomata, Bl.--_Descr._ Orbicular, depressed, thick, rugose; whorls + few, angulated, branched at the angles; aperture pearly, rounded or + sub-quadrate; peritreme continuous, thickened; operculum horny, + composed of numerous whorls.--_Obs._ Several fossil species are found + in the tertiary deposits. D. laciniata, fig. 352. Recent species belong + to tropical climates. + + DELTHYRIS. Dalman. _Fam._ Brachiopoda, Lam.--_Descr._ Hinge more or + less rounded, with distant umbones; both valves convex; with the umbo + of the largest rostrated and deltoid, with a hollow. This genus forms + part of the genus Spirifer, Sow. Fig. 205. D. Plycotes, Dalman. + + DELTOID. ([Greek: D], _delta_.) Triangular. + + DENDOSTREA. Sw. ([Greek: Dendron], _dendron_, tree; [Greek: ostreon], + _ostreon_, oyster.) Ostrea _Crista-galli_, and other species which are + attached to stems of sea-weed and corallines, by means of arms thrown + out from the inner surface of the lower valve. Fig. 181, Ostrea Folium. + + DENTALIUM. Auct. (_Dens_, a tooth.) _Fam._ Maldania, Lam. _Order_, + Cirrobranchiata, Bl.--_Descr._ Tubular, arched, increasing in size + towards the anterior extremity, open at both ends; small aperture + sometimes having a lateral fissure; large aperture round; external + surface ribbed, striated or smooth.--_Obs._ The well known shells + composing this genus are shaped very much like an elephant's tusk, and + are not liable to be confounded with any other genus. The fossil + species are sometimes termed Dentalithes, from _dens_, a tooth, and + _lithos_, a stone. The Dentalia, being true molluscs, are not rightly + placed among the Annelides. Fig. 2, D. octogonum. Found on sandy shores + in most climates. + + DENTATED. Having teeth or raised points. + + DENTICULATED. (Denticulatus, Lat.) Having little teeth or raised + points. + + DEPRESSED. Flattened, pressed down, as the spires of some shells. + + DEXTRAL Spiral Shells. Place the point of a spiral shell towards the + eye, with its mouth downwards; if, as in most instances, the aperture + be on the right side of the axis, it is a _dextral_ shell, if + otherwise, it is _sinistral_ or _reversed_. Balea (fig. 296), and + Clausilia (fig. 295), are examples of reversed shells. + + DEXTRAL Valve. Take a bivalve shell closed, place it before the eye, + with the umbones uppermost, and the posterior side, which may be known + by the ligament towards the observer, whose right side will then + correspond with the right valve of the shell. + + DIADEMA. Ranz. CORONULA Diadema, Auct. fig. 17. + + DIANCHORA. Sow. _Fam._ Pectinides, Lam. _Order_, Palliobranchiata, + Bl.--_Descr._ Inequivalve, attached, oblique, subtriangular; attached + valve, having an opening in the place of the umbo; the other valve + auriculated, with an obtuse umbo; hinge without teeth.--_Obs._ The + green sand fossils contained in this genus differ from Plagiostoma in + being attached. Fig. 175, D. striata. + + DIAPHANOUS. ([Greek: Dia], _dia_, through; [Greek: phainô], _phaino_, + to shine.) Transparent. + + DIAPHRAGM, ([Greek: diaphragma], a partition.) This term is applied to + the septa, by which the chambers of multilocular and other shells are + divided from each other. + + DICERAS. Lam. ([Greek: Dis], _dis_, double; [Greek: Keras], _ceras_, + horn.) _Fam._ Chamacea, Bl. and Lam.--_Descr._ Inequilateral, + inequivalve, attached by the point of the umbo of the larger valve; + umbones prominent, spirally twisted and grooved; hinge with one large + thick tooth in the larger valve; muscular impressions, two in each + valve.--_Obs._ The prominent spiral umbones, which give rise to the + name of this genus, with the circumstance of its being attached by the + point of one of them, is sufficient to distinguish it from any other, + although it appears to approach Isocardia in some characters. In others + it will be found still more nearly to resemble Chama. In fact, from + being attached and irregular, the shells composing this genus have been + considered as Chamæ with produced umbones. The singular fossil shells + composing this genus, are found in granular limestone, near Geneva and + in Normandy. Fig. 154, D. perversum. + + DIDONTA. Schum. SAXICAVA. Auct. + + DIFFUSE. (_Diffundo_, to spread out, to dilate.) A term applied to the + aperture of a univalve shell, when it is spread out or widened into a + flat surface, or digitations. _Alated_ is another term used to express + the same character. Thus, the shells belonging to the family of Alatæ, + in the system of Lamarck, are _diffuse_ in the outer lip. Fig. 402 to + 406. + + DIGITATED. (_Digitus_, finger.) Branched out in long points, as + Ricinula, fig. 413. + + DILATED. Expanded, spread. This term has the same application as + diffuse and alated, explained above. The outer lip of Rostellaria + Columbaria, fig. 403 (Hippochrenes, Montf.), will serve as an example. + + DIMORPHINA. D'Orb. A genus of microscopic Foraminifera. + + DIMYARIA. ([Greek: Dis], _dis_, double; [Greek: muon], _myon_, muscle.) + The first order of Conchifera, Lam. including those molluscs which have + two adductor muscles, and consequently two muscular impressions in each + valve. The Conchifera Dimyaria are divided into Crassipedes, + Tenuipedes, Lamellipedes, and Ambiguæ, fig. 44 to 155. + + DIOICA. Bl. The first division of the class Paracephalophora, Bl. It is + divided into the orders Siphonobranchiata and Asiphonibranchiata, Bl. + + DIPLODON. Spix. HYRIA Syrmatophora, Lam. fig. 144, and UNIO + multistriatus, Lea, are doubtfully quoted by Lea as belonging to this + apparently ill-defined genus of Nayades. + + DIPSAS. Leach. A genus or sub-genus of Nayades, the distinctive + character of which is "having a linear tooth under the dorsal edge." D. + plicatus, fig. 142. + + DISCINA. Lam. ORBICULA, Auct. + + DISCODOMA. Sw. A sub-genus of Lucerninæ, Sw. (Helix), thus described, + "teeth none; aperture angulated; the inner lip nearly obsolete; the + outer only slightly thickened; margin carinated." + + DISCOIDAL. (_Discus_, a circular plane.) A spiral shell is said to be + discoidal, when the whorls are so horizontally convolute as to form a + flattened spire. _Ex._ Planorbis, fig. 311. Orbulites Discus, fig. 479. + + DISCOLITES. Montf. A genus of microscopic Foraminifera. + + DISCONTINUOUS. Interrupted. _Ex._ The siphon of Nautilus is + discontinuous, i. e. its termination in one chamber does not reach to + its commencement in the next. The varices of Triton, occurring in + different parts of the whorls, do not form the continuous ridges which + characterize the generality of the Ranellæ. + + DISCORBITES. Lam. A genus of microscopic Foraminifera. + + DISTANT. The teeth on the hinge of a bivalve shell are said to be + distant when they are remote from the umbones. + + DIVARICATED. Diverging, meeting in a point, as the teeth on the hinge + of Placuna, fig. 184. + + DOLABELLA. Lam. (Dim. from _Dolabra_, a hatchet.) _Fam._ Aplysiacea, + Lam. and Bl.--_Descr._ Hatchet-shaped, arched, covered with a horny + epidermis; posteriorly attenuated, thickened, sub-spiral, anteriorly + plane, broad, thin; posterior margin reflected.--_Obs._ The two or + three species of Dolabella known are inhabitants of the Indian Ocean. + They were placed by Linnæus in his very convenient genus Bulla, under + the name B. dubia. Fig. 255, Dolabella Rumphii. + + DOLIUM. D'Argenville. (_a tun._) _Fam._ Purpurifera, Lam. + Entomostomata, Bl.--_Descr._ Thin, ventricose, oval, or globular, with + a short spire; large aperture terminating in a reflected canal, and + spirally ribbed or grooved external surface; outer lip crenated; inner + lip reflected over part of the body whorl, which terminates in a tumid + varix; epidermis light, horny. Mediterranean and East Indian.--_Obs._ + This genus is distinguished from Cassis by the outer lip, which is not + reflected. The species which are not so rotund as the others, as D. + Perdix, Auct. have been separated under the name Perdix, as generic. + Fig. 420, Dolium Maculatum. + + DONAX. Auct. _Fam._ Nymphacea, Lam. Conchacea, Bl.--_Descr._ Equivalve, + inequilateral, trigonal, with the anterior side short, straight, plane; + the posterior side elongated, drawn to a narrow, rounded termination; + hinge with two cardinal teeth in one valve, one in the other, and one + or two, more or less remote lateral teeth; ligament external; muscular + impressions two in each valve; palleal impression sinuated + posteriorly.--_Obs._ The Capsæ have not the crenated margins, the short + anterior side, and the distinct lateral teeth, which characterize the + Donaces. Some species of Erycina resemble Donax in general form, but + are at once distinguished by the ligamentary pit in the hinge. Sandy + shores in all climates. Fig. 108, D. cuneatus. + + DORSAL. A dorsal shell is one placed upon the back of the animal. The + dorsal margin of a bivalve shell is that on which the hinge is placed; + the opposite margins are termed ventral. The dorsal surface of a spiral + univalve is that which is seen when the aperture is turned from the + observer. The dorsal valve is the uppermost in Brachiopodous bivalves. + The dorsal part of a symmetrical convolute univalve, such as the + Nautilus and Ammonite is that part of the whorls which is at the + greatest distance from the spire, that is, the outer part of the + whorls. Thus the situation of the siphon is said to be dorsal when it + pierces the septum near the outer edge of the whorls. The dorsal part + of symmetrical conical univalves, such as Patella, is the upper part, + on which the apex is placed. + + DORSALIA. Lam. (_Dorsum_, the back.) The first family of the order + Annelides Sedentaria, Lam. containing the genera Arenicola, not a + shell, and Siliquaria, fig. 1, which is now considered as a true + mollusc, and placed next to Vermetus. + + DOSINA. Schum. VENUS Verrucosa, Casina, and similar species. Fig. 119, + a. + + DREISSINA. MYTILUS Polymorphus. Auct. fig. 159. This genus differs from + Mytilus principally in the characters of the animal. The shell is + characterized by a small septiform plate under the hinge within. + Fluviatile, Europe and Africa. + + EBURNA. Lam. (_Eburneus_, ivory.) _Fam._ Purpurifera, Lam. + Entomostomata, Bl.--_Descr._ Oval, thick, smooth, turrited, + umbilicated; spire angulated, acute, nearly as long as the aperture; + aperture oval, terminating anteriorly in a canal, posteriorly in a + groove; outer lip slightly thickened with an anterior notch, which + terminates in a spiral fold surrounding the body whorl; umbilicus + generally covered by the thickened columellar lip.--_Obs._ The + beautiful shells called ivory shells, which originally constituted part + of this genus, are now placed in the genus Ancillaria by authors. They + differ from the present genus Eburna, in having the sutures of the + spire covered with a polished enamel. (A. glabrata, fig. 455.) The + Eburnæ resemble in some respects the genus Buccinum, but a glance at + the figure will enable the reader to distinguish a true Eburna from all + other shells. Fig. 426 is Eburna Zeylanica. A catalogue of 9 species is + given in part 20 of the Conchological Illustrations published by the + Author, accompanied by figures of several species. + + ECHIDNIS. Montf. Described as a straight, chambered, annulated, fossil + shell, computed from the extremely gradual increase in diameter of the + fragments to be at least sixteen feet long. Found in marble from the + Pyrenees. + + ECHINELLA. Sw. A sub-genus of Monodonta. Sw. Malac. page 352. + + EFFUSE. (_effundo_, to pour out.) The aperture of an univalve shell is + said to be effuse when there is a notch in the margin which would + suffer a liquid to escape, and thus prevent it being filled to the + brim. + + EGEON. Montf. A genus of microscopic Foraminifera. + + EGERIA. Lea. (Contrib. to Geol. p. 49, pl. 1.) A genus of fossil + bivalves, described as very variable in form, with or without lateral + teeth, sometimes a crenated margin, &c. The only certain characters + appear to be that they have two diverging cardinal teeth in each valve, + one of which is bifid; and an external ligament. Lea states that the + Egeriæ should be placed between the Sanguinolariæ and the Psammobiæ, + which two latter genera have been united by Sowerby. Fig. 103, E. + Triangulata, from the tertiary formation of Alabama. + + ELENCHUS. Humph. A genus composed of TROCHUS Iris, Auct. and other + similarly formed species. It is the same as CANTHARIDUS of Montfort. + + ELEPHANT'S TUSK. The common name given by dealers to shells of the + genus Dentalium. _Ex._ D. octogonum, fig. 2. + + ELEVATED. A term which is applied by some conchological writers to the + spire of an univalve shell when it consists of numerous whorls drawn + out into a telescopic form. Other authors use the term _elongated_, or + the more simple one '_long_,' to express the degree of elevation. + + ELISMA. Leach. A sub-genus of Bulinus. B. acutus, Auct. Gray, Turton, + p. 185. + + ELLIPSOLITHES. Montf. ([Greek: Elleipsis], _ellipsis_, oval; [Greek: + lithos,] _lithos_, stone.) A genus composed of Ammonites, which instead + of being regularly orbicular, take an elliptical or oval form. This + character appears to be accidental, as some individuals of the same + species, both of Nautilus and Ammonites, are round, while others are + compressed into an oval form. + + ELLIPSOSTOMATA. Bl. ([Greek: Elleipsis], _ellipsis_, oval; [Greek: + stôma], _mouth_.) The third family of the class Asiphonibranchiata, Bl. + The shells of this family are described as of various forms, generally + smooth; the aperture longitudinally or transversely oval, completely + closed by a horny or shelly operculum. This family contains the genera + Rissoa, Phasianella, Ampullaria, Helicina, and Pleuroceras. + + ELLIPTICAL. ([Greek: Elleipsis], _ellipsis_.) Oval. Applied to any + shell or part of a shell, having that form. + + ELMINEUS. Leach. _Order_, Sessile Cirripedes, Lam.--_Descr._ Four + unequal valves, arranged circularly side by side, forming a quadrate + cone; aperture large, sub-quadrate, irregular; operculum composed of + four valves, in pairs.--_Obs._ This genus differs from Conia in the + structure of the shell, the latter being porous. Fig. 22, Elmineus + Leachii. + + ELPHIDIUM. Montf. (Conch. Syst. t. 1. p. 15.) A genus of microscopic + Foraminifera. + + EMARGINATED. (_e_, out; _margo_, border.) Notched or hollowed out. + Applied to the edges or margins of shells, when instead of being level + they are hollowed out, as the outer lip of Oliva, fig. 457, at the + base, and the ventral margins of some bivalves. + + EMARGINULA. Lam. (_e_, out; _margo_, border.) _Fam._ Calyptracea, Lam. + Branchifera, Bl.--_Descr._ Patelliform, oblong or oval; anterior margin + notched or emarginated; apex posteriorly inclined; muscular impressions + wide.--_Obs._ Emarginula elongata, of some Authors, PARMOPHORUS of De + Blainville is commonly called the Duck's bill limpet, from its shape. + The Emarginulæ may be known from Patellæ and other neighbouring genera, + by the notch or slit in the anterior edge. In the genus Rimula, Defr. + fig. 243, this slit is near the apex, and does not reach the margin. + Recent species occur in all climates, but are not numerous. Fossil + species are still more rare, occurring in the Calc-grossièr, Crag and + Oolite. E. fissurata, fig. 241. + + ENA. Leach. A sub-genus of Bulinus. B. Lackhamensis. Mont. + + ENDOSIPHONITES. A genus composed of Ammonites, having the siphon close + to the body whorl, fig. 476. + + ENDOTOMA. Rafinesque. A genus of microscopic Foraminifera. + + ENROULEES. Lam. See CONVOLUTÆ. + + ENSATELLA. Sw. A genus consisting of SOLEN ensis, Auct. fig. 60, and + other species similarly curved. _Genus_ ENSIS, Schum. + + ENSIS. Schum. SOLEN ensis, Auct. and similar species. + + ENTALIS. Defr. DENTALIUM duplicatum, Bl. PHARETRIUM, König. This genus + is described as a small tube, within a larger one, the smaller + extremity of the inner tube projecting beyond that of the outer one. + Deshayes, who describes this genus, expresses a conviction that the + soft parts of the animal must be entirely different from those of the + animal of Dentalium. The genus PHARETRIUM, as described by König in his + "Icones Fossilium Sectiles," is evidently identical with Entalis. It is + placed by him in the family of Pteropoda, but being a fossil shell, + there is some difficulty in finding its place in the system. See + plates, fig. 3. + + ENTELLITES. Fischer. A genus composed of species of TEREBRATULA, + SPIRIFER, and PRODUCTUS, Auct. having the hinge large and the umbones + short. ORTHIS? Dalman. + + ENTIRE. (Integra.) Not interrupted, not emarginated. The peritrême of a + univalve shell is said to be entire when not interrupted by canals or + by the body whorl. _Ex._ Cyclostoma, fig. 304. The palleal impression + is entire, when continued without interruption, or without a sinus. + + ENTOMOSTOMATA. Bl. The second family of the order Siphonibranchiata, + Bl. The shells of this family are described as differing but little + from those contained in the family of Siphonostomata of the same + author, both with regard to the soft parts, and their testaceous + covering. This family partly answers to the Purpuriferæ in the system + of Lamarck, and contains the genera Subula, Cerithium, Melanopsis, + Planaxis, Terebra, Eburna, Buccinum, Harpa, Dolium, Cassidaria, Cassis, + Ricinula, Cancellaria, Purpura, Concholepas. + + EOLIDES. Montf. A genus of microscopic Foraminifera. + + EPIDERMIS. ([Greek: Epi], _epi_, over or upon; [Greek: derma], _derma_, + skin.) The fibrous, horny, external coating of shells, called by the + French, "_Drap marin_," or marine cloth. Lamarck objects to the name + Epidermis because he does not consider the substance as answering to + the cuticle or scarf skin of the human body, but more analogous to the + nails and hair. Gray calls it the PERIOSTRACUM, from the membranous + skin covering the bones of quadrupeds. + + EPIPHRAGM. The membranaceous or calcareous substance by which some + species of molluscs close the aperture of the shell, when they retire + within it to hibernate. When the animal wishes to come forth from his + hiding-place, again to breathe the air, the edges of the Epiphragm are + detached by a chemical process, so that it drops off. The name + Hibernaculum has also been given to this covering. It must not be + confounded with the operculum, which is a permanent portion of the + shell, and is used as a door, fitted to the foot of the animal and + moved at will to open or close the aperture of the shell, whereas the + Epiphragm is produced for the occasion from a mucous secretion of the + animal and dissolved at the edges when no longer wanted, when it drops + off. + + EPISTYLA. Sw. A subgenus of the genus HELIX. E. conical. Sw. Helix + Epistylium, fig. 281. + + EPONIDES. Montf. A genus of microscopic Foraminifera. + + EQUILATERAL. (Æquus, equal; latus, side.) Equal-sided. A term applied + to bivalve shells, when a line drawn down perpendicularly from the apex + would divide the shell into two equal parts. _Ex._ Pectunculus pilosus, + fig. 134. + + EQUIVALVE. (Æquus, equal; _valva_, a valve.) A term applied to a + bivalve shell when the valves are equal to each other in dimensions. + + ERATO. Risso. _Fam._ Convolutæ, Lam.--_Descr._ Ovate, more or less + angulated, smooth or granulated, with a dorsal scar; spire short; + aperture large, angulated, emarginated; columella slightly crenated; + outer lip reflected, denticulated on the inner edge. Suture of the + whorls covered with enamel.--_Obs._ This genus of shells resembles + Marginella in form, but has no folds on the columella. Having a scar or + groove down the back it may be considered intermediate between + Marginella and Cypræa. Fig. 454, E. Maugeriæ. In the Author's + Conchological Illustrations, seven species are enumerated and figured. + + ERUCA. Sw. A subgenus of Clausilia. Sw. Malac. p. 334. + + ERVILIA. Turt. A genus described as "oval, equivalve, equilateral, + closed. Hinge with a single erect tooth closing between two small + diverging ones in the opposite valve: lateral teeth none. Ligament + internal. E. nitens. Turt. Mya. nitens, Auct." + + ERYCINA. Lam. _Fam._ Mactracea, Lam. Conchacea, Bl.--_Descr._ Ovate or + triangular, transverse, equivalve, inequilateral, smooth; hinge with a + ligamentary pit, two diverging cardinal and two lateral teeth in each + valve; muscular impressions two in each valve; palleal impressions + sinuated. East and West Indies and Mediterranean.--_Obs._ This genus is + distinguished from _Mactra_ and _Lutraria_ by the cardinal teeth being + placed one on each side of the ligamentiferous pit; whereas in the last + named genera they are both placed on the anterior side. Fig. 86, E. + Plebeja. + + ERYTHRÆA. The ancient name for CYPRÆA. + + ESCUTCHEON. The impression on the posterior dorsal margin of some + bivalve shells. That on the anterior margin is named the lunule. The + escutcheon is pointed out by the letter _e_ in some of the figures of + Cythereæ. Fig. 117, _a. b. c._ + + ETHERIA. Lam. (_Æther_, air.) Fam. Chamacea, Lam. and Bl.--_Descr._ + Irregular, inequivalve, inequilateral, foliaceous, pearly within, + covered by an olive green epidermis without; hinge callous, undulated, + destitute of teeth; ligament partly external, partly internal, passing + through the hinge on a somewhat raised, callous area in the lower + valve. Muscular impressions elongated, two in each valve, united by a + slender palleal impression. Rivers of Africa.--_Obs._ The irregular, + unequal air-bubbles of the inner surface, whence this genus derives its + name, are very brilliant in some species, and atone, in some measure, + for the rugged ugliness of the exterior. In its irregular form, + foliated structure, and toothless hinge, it resembles OSTREA, from + which it differs in having two muscular impressions. Fig. 155, E. + semilunata. + + EULIMA. Risso. _Fam._ Scalariens, Lam.--_Descr._ Elongated, smooth, + pyramidal; spire long, composed of numerous whorls; apex acute, + slightly tortuous; aperture oval, rounded anteriorly, acute at the + posterior union with the body whorl; outer lip slightly thickened; + columella smooth. Fig. 347, E. labiosa, fig. 348, E. splendidula. A + complete illustrated monograph of this genus of pretty shining little + shells, consisting of 15 known species, is given in parts 52 and 53 of + the Conchological Illustrations by the author. + + EUOMPHALUS. Sow. _Fam._ Scalariens, Lam.--_Descr._ Orbicular, + planorbular spire, with three or four volutions, imbricated above; + smooth below; aperture of a round polygonal form; umbilicus large, + penetrating to the apex of the shell.--_Obs._ This genus of fossils + very nearly resembles Delphinula. The main difference appears to be + that the whorls do not increase so rapidly in size in the former as in + the latter. Fossil, in the Carboniferous Limestone. Fig. 350. + + EXOGYRA. Sow. A genus of fossil bivalves, resembling Chama in shape and + Ostræa in structure, having but one muscular impression in each valve. + Fig. 183. + + EXSERTED. Standing out, protruding. + + EXTERNAL. An external shell is one which contains the animal, and is + not covered by the mantle. + + FASCIATED. (_fascia_, a band.) Banded or striped. Ex. Carocolla + marginata, fig. 277. + + FASCICULATED. (from fasciculum.) A little bunch of hairs or bristles + against each end of each valve, characterizes some species of the genus + Chiton, which are termed fasciculated species. + + FASCIOLARIA. Lam. _Fam._ Canalifera, Lam. Siphonostomata, Bl.--_Descr._ + Elongated, fusiform, ventricose; spire conical, consisting of few + rounded or angulated whorls; aperture wide, terminating in a long + straight open canal: columella lip with several oblique folds, the + lower of which is larger than the rest; operculum horny, + pyriform.--_Obs._ This genus is known from Fusus by the folds on the + columella; from Turbinella, by their obliquity and the last being + larger than the rest. Fig. 386, F. Trapezium. East and West Indies and + Australia. + + FAUNUS. Montf. MELANOPSIS, Auct. + + FERRUGINEOUS. Of an iron rust colour. + + FERUSSINA. Grateloup. STROPHOSTOMA, Deshayes. + + FIBROUS. A shell is said to be of a fibrous structure when a fracture + would present a series of perpendicular fibres, as Pinna. + + FICULA. Sw. A generic group of shells, consisting of those species of + PYRULA, Auct. which have the true pear-shaped character. Fig. 390, P. + Ficus. Sowerby confines the name Pyrula to these species. + + FIMBRIA. Megerle. CORBIS, Lam. + + FIMBRIATED. Fringed; as Murex fimbriatus, a delicate white species, + with broad fringed varices. + + FISSURE. (_Fissura_, a slit.) A slit or cut, a narrow perforation, as + in Emarginula and Fissurella. + + FISSURELLA. Brug. (_Fissura_, a fissure.) _Fam._ Calyptracia, Lam. + Branchifera, Bl.--_Descr._ Patelliform, oval or oblong, radiated; apex + anterior, perforated.--_Obs._ The Fissurellæ are known from Patellæ by + the perforation in the apex. Fig. 245. The catalogue published by the + author in the Conchological Illustrations, enumerates 68 species. + + FISTULANA. Lam. (_Fistula_, a pipe.) _Fam._ Tubicolæ, Lam. Adesmacea, + Bl.--_Descr._ A transversely elongated, equivalve, inequilateral + bivalve, enclosed by a septum within the widest, closed extremity of a + straight calcareous tube. Fistulana is known from Gastrochæna by the + straightness of the tubes, and the oblong state of the valves. Fig. 54, + Fistulana Clava. + + FLEXUOUS. Having windings or bendings. _Ex._ The Tellinæ are known by + the twist or flexuosity in the posterior ventral margin of the shell. + + FLORILLUS. Montf. A genus of microscopic Foraminifera. + + FLUVIATILE. (Fluviatilis.) Belonging to a river or running stream. + _Ex._ Limnæa fluviatilis. + + FLUVIATILE CONCHACEA. See CONCHACEA. + + FOLIATED, or FOLIACEOUS. (From _folium_, a leaf.) When the edges of the + successive layers of which a shell is composed are not compacted but + placed apart from each other, projecting like tiles, the shell is said + to be of a foliated structure. The common Oyster, fig. 180, presents a + familiar example. + + FORAMINIFERA. D'Orb. (_Foramen_, a hole or pit.) An order established + for minute many chambered internal shells, which have no open chamber + beyond the last partition. Lamarck, D'Orbigny, and other writers have + placed them among the Cephalopoda in their systems, but Du Jardin, on + comparing the fossils with some recent species of the same class, + arrived at the conclusion, now generally adopted, that they constitute + a distinct class, much lower in degree of organization than even the + Radiata. Not recognizing these microscopic bodies as shells, properly + so called, but considering them sufficiently numerous and interesting + to form a distinct branch of study, I do not think it desirable to + describe the genera, or to present any arrangement of them in this + work. + + FORNICATED. Arched or vaulted, as the exfoliations on the costæ of + Tridacna Elongata, fig. 157. + + FOSSIL SHELL. A shell is considered to be in a fossil state when, the + soft parts having ceased to exist, it is deprived of all its animal + juices, has lost all, or nearly all its natural colour, and is thus + changed in its chemical composition, when little or nothing is left but + a mere bone, which is embedded in a sedimentary deposit. In this state, + it is fragile, prehensile to the tongue, and either destitute of colour + or tinged with the diluted mineral matters which pervade the stratum in + which it lies. In some cases, the mineral composition of the shell is + so completely changed as no longer to present its proper structure, + consisting of successive oblique layers of shelly matter; but is + altered into a fibrous structure, composed of rhomboidal particles. An + example of this will be found in the Belemnites, which if broken, shew + the perpendicular fibres. In other cases, the matter which has entered + and filled up the cavities of the shell has become silicified, or + changed into flint, and the shell itself has been decomposed and fallen + off, so as to leave nothing but an external or internal cast of its + form, in flint. This is called a Conchyliomorphite by continental + writers. Some of the most important of Geological data are obtained by + a minute comparison of fossil shells, found in various beds, with + recent ones presenting the nearest resemblance to them. Some species of + fossil shells are considered as identical with recent species. And many + Geologists seek to fix the chronology of the different strata by the + number of species which they inclose bearing a resemblance to the + recent species. Indeed, all who would study Geology with success, will + find it indispensably necessary to obtain a thorough knowledge of + Conchology. + + FRAGELLA. Sw. A sub-genus of Monodonta, corresponding with the genus + Clanculus, Montf. consisting of M. Pharaonis (fig. 361), and similar + species. Sw. p. 352. + + FRAGILE. (_Fragilis._) Tender, easily broken. + + FREE SHELL. One that is not attached. + + FREE VALVE. In attached bivalve shells, one only is fixed; the other is + then _free_, as far as to the action of opening and shutting. + + FRESH-WATER SHELLS, (sometimes described as aquatic) are those which + either inhabit rivers, running pools and ditches, in which case they + are _fluviatile_; or wells and ponds of standing water, &c. Fresh-water + shells are either thin and horny in their texture, as the Limneana of + Lamarck; or are covered with a compact, smooth, horny epidermis. They + are generally simple in form, subject to corrosion where the epidermis + is wounded or broken, and are circumscribed with regard to the classes + and genera to which they belong. The family of Nayades includes nearly + all the fresh-water bivalves; and the Melaniana and Limneana are the + principal among univalves. + + FRONDICULARIA. Defr. A genus of microscopic Foraminifera. + + FRONT. The surface of a shell on which the aperture appears. + + FULCRUM. That part of a shell on which any other part rests or turns. + The term is applied more particularly to the tumid part in the hinge of + bivalve shells on which the ligament is fixed. + + FULGUR. Montf. PYRULA perversa, Auct. and such other species as have an + angulated spire. Fig. 388. + + FUSIFORM. (_Fusus_, a spindle.) Shaped like a spindle, swelling in the + centre and tapering at the extremities. _Ex._ Fusus, fig. 387. + + FUSUS. Brug. (A spindle.) _Fam._ Canalifera, Lam. Siphonostomata, + Bl.--_Descr._ Fusiform, turrited, with many rounded whorls; aperture + generally oval, terminating in a long straight canal; operculum horny, + pyriform.--_Obs._ The Fusi are subject to considerable variations in + form. The recent species are numerous and do not appear to be confined + to any climate. The fossil species are also numerous, chiefly abounding + in the tertiary formations. The recent species are mostly tropical. + Fig. 387, F. Colus. + + GALATHÆA. Brug. POTAMOPHILA, Sow. MEGADESMA, Bowd. + + GALEA. Klein. PURPURA, Auct. + + GALEOLARIA. Lam. (From Galea, a helmet or crest.) A genus composed of + species of SERPULA, Auct. Distinguished as being fixed by the side of + the shell, and having the anterior extremity erect, the aperture + terminating in a tongue-shaped projection.--_Obs._ This genus is said + by Lamarck to resemble Vermilia in other respects, but to differ in + having the anterior part raised. Fig. 6, G. decumbens. Africa and + Australia. + + GALEOMMA. Turt. _Fam._ PHOLADARIA, Lam.--_Descr._ Thin, oval, + equivalve, equilateral, with the ventral margin gaping; hinge with one + cardinal tooth in each valve; muscular impressions two, approximate; + palleal impression interrupted, not sinuated; ligament small, partly + internal, partly external, fixed on a prominent fulcrum.--_Obs._ The + wide hiatus in the ventral margins of this equilateral shell prevents + the possibility of confounding it with any other. Four or five recent + species are known, one of which is found on the coast of Sicily, and + also in the British Channel. G. Turtoni, fig. 58. + + GALERICULUS. (_Galericulum_, a little cap or bonnet.) VELUTINA, Auct. + fig. 337. + + GALERUS. Humph. CALYPTRÆA, Lam. + + GAPING. (_Hians._) Bivalve shells are said to gape when the margins do + not meet all round. _Ex._ Gastrochæna, fig. 52. + + GARI. Schum. PSAMMOBIA, Lam. + + GASTEROPODA. Lam. ([Greek: Gastêr], _gaster_, belly; [Greek: pous, + podos], _pus_, _podos_, a foot.) The second order of the class + Mollusca, Lam. containing those molluscous animals whose organs of + locomotion are ventral. Most of the shells belonging to this order are + patelliform, placed upon the back of the animals, which rest or crawl + upon the belly. This order is divided into Pneumonobranchiata, that is, + those which breath air, or land molluscs; and Hydrobranchiata, or those + which breath water, marine or fresh-water molluscs. Fig. 227 to 263. + + GASTRANEA. Schum.? CORBULA, Auct. + + GASTROCHÆNA. Speng. ([Greek: Gastêr], _gaster_, belly; [Greek: chaino], + _chaino_, gape.) _Fam._ Pholadaria, Lam. Pyloridea, Bl.--_Descr._ + Equivalve, regular, inequilateral, with a wide, oblique, ventral + hiatus, enclosed in a curved pyriform tube. Differing from Galeomma in + being a free, oblique shell; from Fistulana, in the oval shape of the + valves, and the curve of the tube; from Aspergillum and Clavagella, in + both valves being free.--_Obs._ The Gastrochænæ are found in the + hollows of massive shells or other marine substances. Fig. 62, G. + Modiolina. + + GASTROPLAX. Bl. UMBRELLA, Lam. De Blainville described this genus from + a specimen in which the shell had been, probably by accident, placed + upon the under part of the animal, and not discovering his error until + afterwards, gave it the above name. + + GEOMITRA. Sw. A sub-genus of Geotrochus, Sw. founded on a trochiform + species of Helix, with coronated nodules on the whorls. Helix + bicarinata, Sow. Zool. Journ. 1, pl. 3, fig. 7. Sw. page 166 and 332. + + GEOPHONUS. Montf. Conch. Syst. t. 1, p. 19. A genus of microscopic + Foraminifera. + + GEOTROCHUS. Sw. HELIX pileus, Auct. (fig. 278,) and other trochiform + species. Divided into the sub-genera Pithohelix, Geotrochus, + Hemitrochus, Gonidormus, and Geomitra. Sw. p. 165 and 166, described at + page 331. + + GEOVULA. Sw. A sub-genus of Melampus (Auricula), consisting of oval + species, resembling Auricula Midæ, fig. 297. + + GERVILLIA. Defr. _Fam._ Margaritacea, Bl. Malleacea, Lam.--_Descr._ + Equivalve, oblong, oblique; hinge long, straight, having small, + irregular, transverse ligamentary pits.--_Obs._ This genus of fossil + shells, found at various geological periods, from the Lias to the + Baculite limestone in Normandy, is now extinct. In general form it + resembles Avicula, but in the hinge it approaches Perna. Fig. 169, G. + Avicularis. + + GIBERULA. Sw. A genus separated from MARGINELLA, Auct. and thus + described, "sub-oval; spire slightly prominent; top of the outer lip + dilated and gibbous; base of the inner lip with plaits; inner lip + broad, spreading. G. Zonata. Enc. Méth. 374, f. 6." + + GIBBOSE or GIBBOUS. (_Gibbosus._) Bunched out, embossed, having a lump + or swelling of any kind. _Ex._ Bulinus Lyonetianus, (fig. 284.) named + Gibbus by De Montfort. Ovulum gibbosum. + + GIBBUS. Montf. BULINUS _Lyonetianus_, Lam. PUPA, Bl. fig. 284. + + GIOENIA. A name given in the Encyclopédie Méthodique, to the plates of + the stomach of Bulla Lignaria. + + GLABELLA. Sw. MARGINELLA Glabella (fig. 437), Goodallii, Auct. and + similar species. + + GLANDINA. Schum. POLYPHEMUS, Montf. + + GLANDIOLUS. Montf. A genus of microscopic Foraminifera. + + GLAUCONOME. Gray. _Fam._ Solenacea, Lam.--_Descr._ Oblong or oval, + transverse, slightly ventricose, equivalve, inequilateral; margins + close, rounded anteriorly, somewhat acuminated posteriorly; hinge + teeth, three in each valve, of which the central in one, and the + posterior in the other, are bifid; muscular impressions anterior, + elongated, marginal; posterior sub-quadrate; palleal impression, having + a long sinus; ligament oblong, external; epidermis thin, horny, green, + folded over the margins.--_Obs._ This shell, of which only one species + is known, inhabits some of the rivers in China. C. Chinensis, fig. 64. + + GLOBIGENERA. D'Orb. A genus of microscopic Foraminifera. + + GLOBOSE. (_Globosus._) Rounded like a globe or ball, as the species of + Helix, represented in fig. 268. + + GLOBULARIA. Sw. A sub-genus of Natica, consisting of globose species. + (Sw. p. 345.) _Ex._ N. Lineata, fig. 328. + + GLOBULUS. Sow. Min. Con. AMPULLARIA, Auct. + + GLYCIMERIS. Lam. _Fam._ Solenacea, Lam. Pyloridea, Bl.--_Descr._ + Equivalve, transverse, oblong, thick, compressed, gaping at both + extremities; hinge callous, without teeth; ligament large, external, + prominent; epidermis thick, black, horny, folded over the margins; + muscular impressions two, distant, running into the irregular palleal + impression which unites them.--_Obs._ But few species of this singular + genus are known; Lamarck describes two species from the Northern Seas. + Blainville is of opinion that they belong to the family of the Nayades. + Fig. 67, G. Siliqua. + + GNATHODON. Gray. ([Greek: Gnathos], _gnathos_, jaw-bone; [Greek: odos], + [Greek: odontos], _odontos_, tooth.) _Fam._ Mactracea, Lam.--_Descr._ + Ovate, posteriorly angulated, equivalve, thick, ventricose, + inequilateral, covered with a greenish brown epidermis; umbo distant, + prominent; hinge having in one valve a sharp, angular, notched, + cardinal tooth, and two lateral teeth, the posterior of which is + elongated, and the anterior angulated, tortuous, shaped like a + jaw-bone; in the other valve, two cardinal and two lateral teeth, the + anterior of which is wedge-shaped; ligament internal, cuneiform, placed + in a deep cardinal pit proceeding from the umbones; muscular + impressions two; palleal impression having a slight sinus.--_Obs._ Only + one species is known, G. cuneatus, fig. 83, from New Orleans. It is + known from all other shells by the character of the hinge. + + GONIATITES. De Haan. A genus composed of species of Ammonites, Auct. in + which the last whorl covers the spire and the sinuations of the septa + are angulated. Fig. 480, G. striatus. + + GONIDOMUS. Sw. A sub-genus of Geotrochus, Sw. PUPA pagodus, Auct. Sw. + p. 332. + + GONIOSTOMA. Sw. A sub-genus of Bulimus, thus described, "spire + elongated, of few whorls; aperture contracted at each end; lips + margined; the pillar curving inwards; the base slightly notched. G. + erubescens, _Sw._ Zool. Journ. i. pl. 5, f. 2." Sw. p. 335. + + GONIOSTOMATÆ. Bl. A family belonging to the order Asiphonibranchiata, + Bl. containing the genera Solarium and Trochus. + + GONOSPIRA. Sw. A sub-genus of Pupa, thus described, "spire perfectly + cylindrical, of equal thickness, the tip obtuse, with the whorls large; + aperture oval; lips thickened; pillar with or without a plait. G. + polanga, _Desh._ Lesson, Voy. pl. 8, f. 8." Sw. p. 333. + + GRANULATED. (_Granum_, a grain.) Covered with minute grains, rough. The + granulated lip of Oniscia, (fig. 409) will serve as an example. + + GRATELOUPIA. Moulins. _Fam._ Nymphacea, Lam.--_Descr._ Equivalve, + inequilateral, sub-cuneiform, rounded anteriorly, sub-rostrated + posteriorly; hinge with three cardinal teeth, a series of five or six + irregular, small, diverging teeth behind the umbones, and one lateral + anterior tooth in each valve; ligament external; muscular impressions + two; palleal impression sinuated posteriorly.--_Obs._ This genus (Donax + irregularis, Bast.) is only known in a fossil state. Fig. 102, G. + Moulinsii. + + GRYPHÆA. Lam. (From Gryps, a griffin.) _Fam._ Ostracea, Lam.--_Descr._ + Inequivalve, free; lower valve large, concave; with the umbo prominent, + incurved; upper valve small, flat, opercular; hinge toothless, with a + curved, depressed area; one muscular impression.--_Obs_. These shells, + which approach the Oysters, are of a more regular form, and are + remarkable for the curved, produced beak of the lower valve. They are + only known in a fossil state, belonging to the more ancient strata. + Fig. 182, G. incurva. The recent species mentioned by Lamarck is not a + true Gryphæa. + + GYMNOLEPAS. A generic name used by De Blainville to include OTION and + CINERAS, Leach. + + GYMNOSOMATA. Bl. The second family of the order Aporobranchiata, in the + system of De Blainville. The animals belonging to this family are + destitute of shells. + + GYPIDEA. Dalman. A genus of Brachiopoda, thus described, "Larger valve + with the umbo rostrated, remote from the hinge; with the canal large, + deltoid; bilocular within." PENTAMERUS, Sow. Fig. 210. 211, G. + Conchidium, copied from Dalman. + + GYROGONA. Lam. A genus of microscopic Foraminifera. + + GYROIDINA. D'Orb. A genus of microscopic Foraminifera. + + HALIOTIDÆ. Sw. A sub-genus of Calyptræa. CALYPTRÆA dilatata. Sowerby's + Genera of Shells, fig. 9. + + HALIOTIS. Auct. ([Greek: als], _als_, sea; [Greek: ous], [Greek: ôtos], + _otos_, ear.) _Fam._ Macrostomata, Lam. Otides, Bl.--_Descr._ Auriform, + broad, depressed, pearly within, rough, costated, tuberculated without; + spire short, flat, consisting of one or two whorls; aperture wide; + ovate; columella laminar, flat, oblique; a spiral series of + perforations running along the dorsal margin.--_Obs._ The splendid + shells belonging to this genus are remarkable for the pearly + iridescence of the inner surface, and the row of holes following the + course of the spire. The soft parts are eaten in Guernsey and Jersey, + and reckoned delicious. They belong to temperate and tropical climates. + Fig. 338, H. rubra. 339, Padollus, Montf. + + HALIOTOID. (_Haliotis_ and [Greek: eidos], _eidos_, form.) Ear-shaped. + + HAMIFORM. (_Hamus_, a hook.) Curved at the extremity. + + HAMITES. Parkinson. (_Hamus_, a hook.) _Fam._ Ammonacea, Lam.--_Descr._ + Elongated, cylindrical, chambered, recurved at the smaller extremity, + annulated; septa lobed and sinuated.--_Obs_. This remarkable fossil + from the Baculite limestone in Normandy, differs from Baculites in + being curved at one extremity, a circumstance from which its name is + derived. Some small species are found in Chalk-Marle, Folkstone. Fig. + 484*. H. cylindricus. + + HARPA. Brug. (_Harpa_, a harp.) _Fam._ Purpurifera, Lam. Entomostomata, + Bl.--_Descr._ Oval, ventricose, longitudinally and regularly costated; + spire short, with rounded, dome-like whorls; aperture wide, + emarginated; outer lip thickened, reflected, composing the last costa + or rib; inner lip polished, spread over part of the body whorl, + terminating in a point.--_Obs._ This beautiful genus of shells is so + clearly defined by the regular, longitudinal ribs that adorn the + external surface, suggesting the idea of a stringed instrument, that + there is no danger of confounding it with any other. H. multicostata, + (Buccinum costatum, Linn.) and H. ventricosa, are among the most + elegant of the testaceous productions of the sea both in form and + colouring; the former is rare. The recent species are not numerous, + they inhabit the Indian Ocean. A fossil species occurs at Grignon, near + Paris. Fig. 419, H. ventricosa. + + HARPAX. Parkinson. Part of PLICATULA, Auct. + + HARPULA. Sw. A group of shells separated from VOLUTA, Auct. thus + described, "shell generally tuberculated or longitudinally ribbed; apex + of the spire papillary, smooth, and in general distorted; pillar with + numerous distinct plaits; the upper, small and slender, the lower, + thickest and shortest."--_Type_, H. Vexillum. (Voluta, Auct.) + + HAUSTATOR. Montf. A genus proposed to include those species of + TURRITELLA, Auct. which have angulated whorls. + + HAUSTELLARIA. Sw. A sub-genus of Murex, consisting of species with long + canal and no spines. Murex Haustellum, fig. 396. + + HAUSTRUM. Humph. PURPURA, Lamarck. + + HELCION. Montfort. A genus composed of species of Patella, which have + the apex distinctly and prominently bent forwards. _Ex._ P. pellucida, + fig. 230. + + HELENIS. Montf. A genus of microscopic Foraminifera. + + HELICELLA. Fer. One of the sub-genera into which De Ferussac has + divided the genus Helix, consisting of depressed species with large + umbilicus, such as Helix Algira, fig. 279. Gonites Montf. + + HELICIFORM. Shaped like shells of the genus Helix. + + HELICIGONA. One of De Ferussac's sub-genera of the genus HELIX, + consisting of angulated species, such as Carocolla Lamarckii, fig. 277. + + HELICINA. Lam. _Fam._ Colimacea, Lam. Ellipsostomata, Bl.--_Descr._ + Globose, compressed, or angulated, generally light and thin; aperture + trigonal or semilunar; outer lip thickened and generally more or less + reflected; inner lip spread over the body whorl, frequently callous + near the columella, which is short, and terminates in a notch, angle, + or slight callosity.--_Obs._ This genus of land shells, distinguished + from the genus Helix, by having an operculum and a thickened columellar + lip, differs also from Cyclostoma in having the aperture semicircular + or angular, the peritreme discontinuous and the operculum concentric. + These shells are generally small in size, and simple in form. Lamarck + describes only three or four species. Mr. Gray described some others in + the Zoological Journal, and in a work shortly to be published by the + author, a monograph of the genus will contain descriptions and figures + of at least 60 distinct species; some of which have been lately brought + to this country by Mr. Cuming from the Philippine Islands. They mostly + belong to tropical climates. + + HELICITES. Bl. Part of the genus NUMMULITES, Lam. ROTALITES and EGEON, + Montf. + + HELICOGENA. Fer. A sub-genus of Helix, consisting of species, which, + like the common garden snail, fig. 268, are globose and simple in form. + + HELICOLIMAX. Fer. VITRINA, Drap. H. Pellucida, fig. 263. + + HELICOPHANTA. Fer. A sub-genus of Helix, consisting of ear-shaped + species with large open apertures. + + HELICOSTYLA. Fer. A sub-genus of Helix, consisting of species with + numerous whorls, as H. Epistylium, fig. 281. + + HELISOMA. Sw. A sub-genus of Planorbis. Sw. p. 337. + + HELIX. Auct. _Fam._ Colimacea, Lam.--_Descr._ Orbicular, light, + generally globular; spire short, last whorl ventricose, aperture + oblique, peritreme reflected, interrupted by the most prominent part of + the body whorl; columella confluent with the outer lip, and contiguous + to the axis of the shell. No operculum; a thin epidermis.--_Obs._ The + land shells composing this genus are found in all parts of the world; + the common snail, H. Aspersa, is well known as a destructive animal in + our gardens. The genera Helix, Achatina, Bulinus, Clausilia, Anostoma, + &c., have been united under one generic name by De Ferussac, and again + divided under the following sub-generic names, each of which we shall + illustrate by a figure. GENUS HELIX: _Sub-genus_ 1, _Helicophanta_, + consisting of species with large apertures, like Vitrina; Helix + brevipes. _S. gen. 2_, _Cochlohydra_, Succinea Amphibia, Drap. _S. gen. + 3_, _Helicogena_, consisting of the common species with the last whorl + large; Helix Hæmastoma, H. Contusa, (Streptaxis, Gray,) H. Aspersa. _S. + gen. 4_, _Helicodonta_, consisting of species with teeth or folds on + the columella; Polydonta, Montf. Anostoma, Helix Nux-denticulata. _S. + gen. 5_, _Helicigona_, Carocolla, Geotrochus. _S. gen. 6_, _Helicella_, + consisting of depressed species with a large umbilicus; H. Citrina + (Naninia, Gray.) _S. gen. 7_, _Helicostyla_, consisting of species with + a simple aperture, like the Helicogenæ, but with the whorls increasing + very gradually; H. epistylium. _S. gen. 8_, _Cochlostyla_, Bulinus. _S. + gen. 9_, _Cochlitoma_, Achatina. _S. gen. 10_, _Cochlicopa_, Polyphemus + Glans. _S. gen. 11_, _Cochlicella_, Bulinus decollatus. _S. gen. 12_, + _Cochlogena_, Azeca tridens. _S. gen. 13_, _Cochlodonta_, Pupa Uva. _S. + gen. 14_, _Cochlodina_, Clausilia macascarensis, Balea fragilis. The + last three sub-genera are included in the genus Odostomia of Fleming. + We give an example of each of these sub-divisions, for the sake of + presenting the reader with the principal variations to which the genus + is subject. The established genera will be characterized in their + places. Fig. 254 to 281. + + HELIXARION. Fer. VITRINA, Drap. Differing from Helicolimax in the + structure of the animal. Fig. 262. + + HEMICARDIUM. Cuv. ([Greek: hêmisus], _hemisus_, half, [Greek: Kardia], + _cardia_, heart.) CARDIUM Hemicardium, fig. 123**, and several similar + species. + + HEMICYCLA. Sw. A sub-genus of Helix. + + HEMICYCLONOSTA--see CARDILIA. + + HEMICYCLOSTOMATA. Bl. The fourth family of Asiphonibranchiata, Bl. + described as "more or less globular, thick, flattened on the under + side; spire very short; aperture large, semilunar, entire; its outer + edge hollowed; its inner or columellar edge straight, sharp and + septiform." This family answers to the genus _Nerita_ of Linnæus, and + to the family Neritacea of Lamarck. It contains the genera Natica, + Nerita, Neritina, and Navicella. + + HEMIMACTRA. Sw. A sub-genus of Mactra, thus described: "General form of + _Mactra_; but the cardinal teeth entirely wanting; cartilage internal, + central, in a large triangular cavity; lateral teeth 2/1, distinct, + lateral, striated: connected to the _Glycimeri_. H. gigantea, _Lam._ v. + 472. No. 1. grandis, _Sw._ Sp. Nov." Sw. p. 369. + + HEMIMITRA. Sw. A sub-genus of Paludomus, Sw. (Melanianæ.) + + HEMIODON. Sw. A sub-genus of Anodon, described as having "Tubercles or + undulations on the hinge margin. H. undulatus, purpurascens and + areolata." + + HEMISINUS. Sw. A sub-genus of Melania, thus described: "General shape + of _Melania_; but the base of the aperture is contracted and + emarginate; outer lip crenated. H. lineolata, Griff. Cuv. xii. pl. 13. + fig. 4." + + HEMITOMA. Sw. A sub-genus of Emarginula, thus described: "Patelliform; + the fissure not cut through the shell, but merely forming an internal + groove. H. tricostata, _Sw._ Sow. Gen. fig. 6." + + HEMITROCHUS. Sw. A sub-genus of Geotrochus, Sw. H. hæmastoma. Sw. p. + 331. + + HEPTALASMIS. Leach. ([Greek: Hêpta], _hepta_, seven; [Greek: elasma], + _elasma_, plate) A small shell resembling Pentelasmis, from which it + differs in the number of valves, being composed of seven valves + according to Leach, and of eight according to Gray, who counts the + dorsal valve, which is jointed, as _two_, and names his genus + Octolasmis. Fig. 41, H. Warwickii. + + HERCOLES. Montf. A microscope shell, appearing from De Montfort's + figure to resemble TROCHUS _Imperialis_ in shape. + + HERION. Montf. LENTICULINA, Bl. Microscopic. + + HERMAPHRODITA. Bl. The third sub-class of Paracephalophora, Bl. divided + into, Sect. 1, _symmetrical_, containing the orders Cirrobranchiata and + Cervicobranchiata; Sect. 2, _non-symmetrical_, order, Scutibranchiata. + + HERMES. Montf. A genus composed of CONUS _Nussatella_, Auct. and other + elongated, cylindrical, striated species. Fig. 460. + + HETEROBRANCHIATA. Bl. The fourth order of the class Acephalophora, Bl. + containing no testaceous mollusca. + + HETEROPODA. Lam. The fifth order of the class Mollusca, Lam. This order + contains but one genus of shells, viz. Carinaria, fig. 488. + + HETEROSTEGINA. D'Orb. A genus of microscopic Foraminifera. + + HIATELLA. Daud. Fam. Lithophagidæ, Lam. A genus composed of species of + Saxicava, Auct. which have sharp, angulated, posterior ridges, a + circumstance which occurs to many species in a young state, which + afterwards become rounded off. Fig. 95, Hiatella biaperta. + + HIATULA. Sw. A genus proposed to include those species of Oliva, Auct. + which have widened apertures. _Ex._ O. Subulata, fig. 458. + + HIBOLITHES. Montf. A genus composed of species of Belemnites, Auct. + which are swelled towards the apex, and contracted near the centre. B. + Hastatus, Auct. fig. 468. + + HIMANTOPODA. Schum. MALLEUS, Auct. + + HINGE. The edge of the bivalve shells near the umbones, including the + teeth and ligament. + + HINNITES. Defr. A generic name proposed for PECTEN PUSIO, Auct. + remarkable for the irregularity of the outer surface, which would + almost lead to the belief of its being an attached shell. Fig. 173, H. + Pusio. + + HIPPAGUS. Lea. (_Horse boat._) A minute fossil shell, resembling + Isocardia in form, but destitute of hinge teeth. H. Isocardioides, fig. + 128. + + HIPPOCHRENES. Montf. Species of ROSTELLARIA, Auct. with the outer lip + spread. Fig. 403. R. Columbaria. + + HIPPONYX. ([Greek: Hippos], _hippos_, horse; [Greek: onux], _onyx_, + nail or hoof.) _Fam._ Rudistes, Lam.--_Descr._ Inequivalve, + sub-equilateral, rather irregular, destitute of ligament and hinge + teeth; lower valve attached, flat, sub-orbicular, with a muscular + impression, composed of two lunulate portions, meeting at one + extremity, and presenting the form of a horse-shoe; upper valve + conical, with the apex inclined backwards, and the muscular impression + marginal.--_Obs._ The earlier naturalists having only met with the + upper valve of these shells, placed them among the patelliform + univalves; to some of which, particularly Pileopsis, they bear a very + strong resemblance. The species of Hipponyx are numerous, and till + lately only known in a fossil state. The recent species belong to + tropical climates: the fossil species are found in the tertiary beds. + Fig. 199, H. Cornucopia. + + HIPPOPODIUM. Conybeare. _Fam._ Cardiacea, Lam.--_Descr._ Equivalve, + obliquely transverse, heavy, deep, inequilateral, umbones incurved; + ventral margin sinuated, so as to give a bilobed appearance to the + shell; hinge incrassated, with one rugged oblique tooth.--_Obs._ These + fossils are found in the upper beds of Lias. Fig. 129, H. Ponderosum. + + HIPPOPUS. Lam. ([Greek: Hippos], hippus; [Greek: pous], _pous_, foot.) + _Fam._ Tridacnacea, Lam.--_Descr._ Equivalve, inequilateral, regular, + subquadrate; lunule closed, flat, with crenulated edges; ventral margin + deeply undulated; external surface fluted, with radiating ribs, which + are transversely fringed with rows of tubular spines; hinge margin + thick, with two long, compressed posterior lateral teeth in one valve, + three in the other; ligament marginal, external.--_Obs._ The shell thus + described is rightly separated from Tridacna, on account of the + anterior dorsal margins being closed; whereas in Tridacna there is a + wide hiatus. Only one species of this genus is known, which receives + its name from its resemblance in form to a horse's foot, when held with + the flat anterior dorsal margin downwards. Few shells are found to + concentrate so many beauties as the Hippopus Maculatus, commonly called + the Bear's-paw-clam; the delicate whiteness of the interior, the + undulating edge, the radiated fluted columns, adorned at intervals by + crisped fringes, and the richness of the variegated colouring, are such + as to secure the admiration of the most superficial observer. From the + Indian Archipelago. Fig. 156, H. Maculatus. + + HIPPURITES. Montf. _Fam._ Orthocerata, Lam. Rudistes, Bl.--_Descr._ + Tabular, rude, irregular, attached; lower valve cylindrical, more or + less lengthened, apparently divided into sections by septa (considered + by some authors as merely projecting layers of growth) having one or + two lateral tubes within; upper valve round, flat, fixed on the + aperture of the tubular valve like an operculum.--_Obs._ This genus is + known only in a fossil state, and but very imperfectly. Lamarck places + it among his chambered Cephalopoda, &c. De Blainville, considering it a + true Bivalve, enumerates it among his Rudistes. Cretaceous group. Fig. + 198, H. Cornucopia. + + HORTOLUS. Montf. SPIROLINA, Lam. Microscopic. + + HYALÆA. Auct. (_Hyalus_, glass.) _Fam._ Pteropoda, Lam. Thecosomata, + Bl.--_Descr._ Globose, glassy, transparent, with a triangular opening + at the upper part where the dorsal portion advances beyond the ventral; + ventral portion vaulted; dorsal more flat; lower extremity + tridentate.--_Obs._ The singular structures composing this genus were + formerly taken for bivalves, and named Anomia Tricuspidata, &c. They + are now known to belong to the class of molluscous animals, called + Pteropoda, from the wing-shaped organs of locomotion. A species of + Hyalæa occurs in Sicily in a fossil state. Recent species are found in + the Mediterranean, Atlantic, and Indian Oceans. Fig. 226, H. + Tridentata. + + HYALINA, Studer. VITRINA, Drap. + + HYALINE. (_Hyalus_, glass.) Glassy, thin, transparent--_Ex._ Carinaria + Mediterranea, fig. 488. + + HYDROBRANCHIATA. Bl. The first section of the order Gasteropoda, Lam. + containing Molluscs which breathe water only; divided into the families + Tritoniana, Phyllidiana, Semi-phyllidiana, Calyptracea, Bullæana, and + Aplysiana. + + HYGROMANES. Fer. A sub-division of Helix, containing H. limbata, Auct. + &c. Gray's Turton, p. 143. + + HYRIA. Lam. A genus composed of species of Nayades, distinguished by + their alated dorsal margins, and lamellated lateral teeth. South + America. HYRIA corrugata, fig. 143, Hyria Syrmatophora, fig. 144. + + HYRIDELLA. Sw. A genus of "Hyrianæ," Sw. described as differing from + HYRIA, Auct. in having a cardinal as well as a lateral tooth in each + valve. Sw. p. 380. + + HISTRIX. Humph. RICINULA, Auct. + + JANERA. Schum. A genus composed of species of Pecten, Auct. having + oblique plicæ or calli on each side of the ligamentary pit. _Ex._ P. + plica, fig. 172. Decadopecten, Rüppell. + + JANTHINA. Auct. (_Janthum_, a violet.) _Fam._ Neritacea, Lam. + Oxystomata, Bl.--_Descr._ Sub-globose, thin, fragile; spire short, + consisting of few whorls; aperture angulated, at the anterior junction + of the inner and outer lips; columella tortuous, contiguous to the + axis; outer lip thin, sinuated in the centre.--_Obs._ The shells + composing this genus are celebrated for their beautiful purple colour. + The animal possesses a small vesicular process, which keeps it floating + on the surface of the water; it exudes a purple secretion when + irritated. It is occasionally floated on to the shores of most + temperate and tropical countries. Fig. 333, J. Fragilis. + + JATARONUS. Adanson. CHAMA, Auct. + + IBERUS. Montf. CAROCOLLA, Lam. + + IBLA. Leach. _Fam._ Pedunculated Cirripedes, Lam.--_Descr._ Four + valves, posterior pair elongated, anterior pair short, triangular; + pedicle cylindrical, contracted at the base, hairy.--_Obs._ I. + Cuveriana (fig. 40) is brought from Kangaroo Island. + + ICTHYOSARCOLITES. Desmarest. _Fam._ Ammonacea, Lam.--_Descr._ + Chambered, slightly arcuate, laterally compressed; septa simple, + leaving triangular articulations imbricated like the thick muscles of a + fish. + + JESITES. Montf. A minute fossil resembling GALEOLARIA. + + ILOTES. Montf. ORBICULINA, Bl. A genus of microscopic Foraminifera. + + IMBRICARIA. Schum. CONOHELIX, Sw. + + IMBRICATED. (_Imbrex_, a tile.) A shell is said to be imbricated when + the superficial laminæ are arranged over each other in the manner of + tiles. + + IMPERATOR. Montf. A genus composed of species of the genus TROCHUS, + Auct. with whorls angulated and stellated, having an umbilicus. _Ex._ + T. Imperialis. Some of the shells named Imperator in the British Museum + belong to the genus Calcar, Montf. having no umbilicus. + + IMPRESSION. See MUSCULAR IMPRESSION. + + INCRASSATED. (_Crassus_, thick.) Thickened, as the hinge of Glycimeris, + fig. 67. + + INCURVED. Turned inwards or bent forwards. Applied to symmetrical + shells, when the point of the apex turns towards the anterior + extremity, as in Patella. The apex of a shell is said to be incurved + when it is bent inwards, but not sufficiently so to be described as + spiral. _Ex._ Ammonoceras, Lam. fig. 477. + + INDENTED. (_In_, in; _dens_, a tooth.) Exactly the reverse of DENTATED; + meaning a series of small cavities, such as might be produced by the + entrance of teeth. The cast of a dentated surface would be indented. + + INEQUILATERAL. (_Æquus_, equal; _latus_, a side.) A term applied to a + bivalve shell when its extent on one side of the umbones is greater + than that on the other. When the sides are nearly equal, the term + _sub-equilateral_ is used. + + INEQUIVALVE. (_in_; _æquus_, equal; _valva_, valve.) The two principal + valves differing from each other in diameter or convexity. + + INFERIOR VALVE is that which is attached to sub-marine bodies. Only + applied to attached bivalves. + + INFEROBRANCHIATA. Bl. The fourth family of the second section of + Paracephalophora Monoica, Bl. containing no testaceous mollusca. + + INFLATED. Swelled, as Bulla, fig. 250, 252. This term can only be + applied to rotund shells of a light, thin texture. In other cases we + should use the word VENTRICOSE. + + INFLECTED. Turned inwards. This term is applied to the outer lip of a + spiral shell when it turns towards the body whorl. This is the case in + Cypræa, fig. 446. See REFLECTED. + + INFUNDIBULUM. Montf. (_A funnel._) A genus formed of those species of + CALYPTRÆA, Lam. which, having a spiral septum, so nearly resemble + Trochus that some authors have placed them in that genus. One species + named Patella Trochiformis. Recent from South America, fossil from the + tertiary beds. Fig. 237, 238, Calyptræa (Infundibulum) Pileus. + + INNER LIP. That edge of the aperture of an univalve shell which is near + to the imaginary axis, as distinguished from the outer lip, or that + which is on the opposite side. + + INOCERAMUS. Sow. _Fam._ Malleacea, Lam. Margaritacea, Bl.--_Descr._ + Thick, inequivalve, sub-equilateral, triangular, deep, with the umbones + incurved; hinge formed of a series of transverse grooves.--_Obs._ The + larger valves of these fossil shells resemble the larger valve of + Gryphæa; but the hinge is quite distinct. The species described in + Mineral Conchology are found in the blue marl, at Folkstone, and in the + chalk. I. Lamarckii, (Catillus, Brong.) fig. 167. + + INTERNAL CAST. The mould of a fossil shell, composed of matter which + entered the shell in a soft state, and has subsequently hardened, when, + the shell dropping off, the hardened substance which filled it is left + to represent its internal form. + + INTERNAL LIGAMENT. A term used by some conchological writers signifying + that the ligament of a bivalve shell is placed within the closed part + of the hinge, so as not to be seen when the valves are shut. But the + substance, formerly called the internal ligament, is now distinguished + from the true ligament both in structure and use; and is now more + properly called the cartilage, so that when the ligament is said to be + internal, it must be understood that the internal cartilage is + unaccompanied by any ligament properly so called, and when a shell is + described as having two ligaments, as in the case of Amphidesma, it + means that the two substances are so far removed from each other in the + hinge that they are no longer confounded together. + + INTERNAL SHELL is one which is enclosed in the soft parts of the + animal, as a bone is enclosed in the flesh of a human body. The Limax, + or common garden slug, which has a testaceous shield beneath its + mantle, is an instance of this. + + IO. Lea. A genus composed of several species of fresh-water shells + which are considered as differing from Melaniæ in having the anterior + termination of the aperture produced into a point in some degree + resembling the caudal canals of shells belonging to the family of + Canalifera, which are marine. Io fusiformis and spinosus are described + and figured in Lea's work on the genus Unio. + + JODAMIA. Defr. A genus resembling Birostrites, except that in Jodamia + one valve overwraps the other, while in Birostrites the circumference + of the valves is equal. + + IPHIGENIA. Gray. A sub-genus of Clausilia, C. biplicata, &c. Auct. + Gray's Turton, p. 214. + + IRIDEA. Sw. A genus of "Hyrianæ," Sw. thus described:--"Oblong ovate; + bosses small, depressed, sulcated; inner cardinal tooth placed beneath + the outer. I. granosa, _Lam._ En. Méth. 248. fig. 9." + + IRIDINA. Auct. A genus belonging to the Nayades, and resembling the + ANODONTÆ, Auct. but its peculiar characteristic is that the hinge + lamina is tuberculated or crenulated in its whole length. Sowerby + unites all the genera of the family into the genus UNIO. Fig. 150, I. + Elongata. + + IRREGULAR SHELLS, are those which, being attached to, or imbedded in + other marine bodies, have no constant form, but are modified in shape + according to the substances to which they are fixed, as the Chamacea, + fig. 153 to 155. + + IRUS. Oken. Comprehending PANDORA, PETRICOLA, SAXICAVA, &c. + + ISOCARDIA. Lam. ([Greek: Isos], _isos_, similar; [Greek: Kardia], + _cardia_, heart.) _Fam._ Cardiacea, Lam. Chamacea, Bl.--_Descr._ + Cordiform, regular, equivalve, ventricose, with distant, diverging, + involute, free umbones; hinge with two compressed cardinal, and one + distant, compressed lateral teeth in each valve; ligament external, + bifid, diverging in the direction of the umbones.--_Obs._ The shells + composing this genus are remarkable for the beautiful curvature of the + diverging umbones. European and Chinese Seas. Fig. 126, I. Moltkiana. + + KEEL. A flattened ridge, resembling the keel of a ship. As that on the + back of Carinaria vitrea, fig. 488, and those on the whorls of some + spiral shells. A shell characterized by a keel or keels is said to be + carinated. + + KELLIA. Turton, MYA Suborbicularis, Montague. + + LABIS. Oken. MONODONTA, Lam. + + LABIUM, or inner lip,--is used to express that side of the aperture + which is nearest to the axis and generally contiguous to the body + whorl. The lower part of this, when sufficiently distinct from that + part which overwraps the body whorl, is called the Columella. + + LABRUM, or outer lip,--is the edge of the aperture at the greatest + distance from the axis. + + LACINEA. Humph. CHAMA, Lam. + + LACUNA. Turt. _Fam._ Turbinacea, Lam.--_Descr._ Globose, thin, covered + with a smooth epidermis; spire short, consisting of few rapidly + increasing whorls; aperture semilunar, rounded at the extremities; + columella oblique, reflected over part of the umbilicus; umbilicus + forming a lengthened area behind the columella. Northern shores. Fig + 364, L. Pallidula. + + LAGENULA. Montf. A genus of microscopic Foraminifera. + + LAMELLATED. (_Lamella_, a thin plate.) When the layers of which a shell + is composed, instead of being compacted into a solid mass, are + separated, overlying each other in the manner of tiles, with the edges + prominent, the structure is said to be lamellated or foliaceous. + + LAMELLIBRANCHIATA. Bl. The third order of the class Acephalophora, Bl. + consisting of bivalve shells, divided into the families Ostracea, + Subostracea, Margaritacea, Mytilacea, Polydontes, Submytilacea, + Chamacea, Conchacea, Pylorides, Adesmacea. + + LAMELLIPEDES. Lam. (_Lamella_, a thin plate, _pes_, a foot.) The third + section of the order Conchifera Dimyaria, containing bivalves, with the + foot of the animal broad and thin; divided into the families Conchacea, + Cardiacea, Arcacea, Trigonacea, Nayades. Fig. 111. to 152. + + LAMPAS. Montf. LENTICULINA, Bl. A genus of microscopic Foraminifera. + + LAMPRODOMA. Sw. A genus of "Olivinæ," Sw. thus described:--"Mitriform; + spire produced, conic; resembling MITRELLA in shape, but the suture is + channelled; the aperture effuse at the base, contracted above; lower + half of the pillar with 6 to 7 plaits. Volutella, Zool. Ill. ii. + series, pl. 40. f. 1. (_fig. 86._ )" Sw. p. 321. + + LAMPROSCAPHA. Sw. A sub-genus of "Anodontinæ," Sw. thus + described:--"Shell not winged, elongate, pod-shaped; teeth none; bosses + near the anterior extremity. Tropical America only? L. ? elongata. + _Sw._ Zool. Ill. i. 176. ensiforme, _Spix._ Braz. Test. siliquosa. + Braz. Test. pygmæa. Ib." Sw. p. 381. + + LAMPROSTOMA. Sw. A sub-genus of Canthorbis (Trochus), described at p. + 350, Lardn. Cyclop. Malac. + + LAMPUS. Humph. TEREBRATULA, Lam. + + LANCEOLATE. Lengthened like a lance. + + LANISTES. Montf. Reversed species of AMPULLARIA, fig. 319. + + LAPLYSIA. See APLYSIA. + + LAPLYSIACEA. Lam. (properly Aplysiacea) A family belonging to the first + section of the order Gasteropoda, Lam. containing the genera Aplysia + and Dolabella. Fig. 254, 255. + + LARVA. Humph. FISSURELLA, Lam. + + LATERAL. (_Latus_, a side.) The lateral teeth are those which, taking + their rise near the umbones, proceed to some distance towards the sides + of the shell; as distinguished from the cardinal teeth, which receive + their full developement close to the umbones. Lateral muscular + impressions are those which are placed at a distance from each other, + on the opposite sides of the shell. + + LATIAXIS. Sw. A genus of "Eburninæ," Sw. corresponding with the genus + Trichotropis. Sow. (Sw. Malac. p. 306.) + + LATIRUS. Montf. A genus composed of species of FUSUS, Auct. which have + an umbilicus and are turriculated. + + LAURIA. Gray. A sub-genus of PUPA, containing P. umbilicata, &c. + (Gray's Turton, p. 193.) + + LEGUMINARIA. Schum. A genus composed of species of SOLEN, Auct. which + have an internal longitudinal bar or rib. Fig. 61. S. Radiatus, Lam. + + LEILA. Gray? Described as having the hinge edge smooth like Iridina, + but having a "sharp siphonal inflexion." (Syn. B. M. p. 142.) + + LEIODOMUS. Sw. A genus of "Buccininæ," Sw. consisting of Terebra + vittata and other similar species. This genus corresponds with Bullia, + Gray. + + LEIOSTOMA. Sw. A genus of "Fusinæ," Sw. thus described, "Equally + fusiform," (with Fusus) "but ventricose in the middle; shell entirely + smooth, almost polished; inner lip thickened, and vitreous; base of the + pillar very straight. Fossil only. (_fig. 75._) L. bulbiformis. En. + Méth. 428. f. 1." + + LEMBULUS. Leach. A genus composed of oval species of NUCULA, resembling + N. margaritacea, fig. 137. + + LENDIX. Humph. PUPA, Lam. + + LENGTH. See MEASUREMENT. + + LENTICULAR. (_Lens._) Of a circular, convex form, as Pectunculus, fig. + 134. + + LENTICULINA. Lam. A genus of microscopic Foraminifera.--_Descr._ + Lenticular, sub-discoidal, compressed, convolute, symmetrical; aperture + notched; chambers few in number; visible on the exterior, radiating + from the centre of the disk. + + LEPADICEA. Bl. The first family of the class Nemantopoda, Bl. This + family consists of the same animals which constitute the Pedunculated + Cirripedes of Lamarck, and part of the genus Lepas in the system of + Linnæus. It contains the genera Gymnolepas, Pentalepas, Polylepas and + Litholepas. + + LEPAS. ([Greek: Lepas], _lepas_, a rock.) The Linnæan name Lepas + contains all the Cirripedes or Multivalves, the different kinds of + which are not distinguished in the accounts given by early writers of + the habits of the animals. (Fig. 14 to 43.) It was formerly applied to + the Limpets or Patella. In fact, the ancient definition was "Concha + petræ adhærens," and would apply to any shells attached to rocks. + + LEPTÆNA. Dalman. A genus belonging to the Brachiopoda; and thus + described:--"Hinge compressed, rectilinear, frequently exceeding the + width of the shell." It forms part of the genus Producta, Sow. Fig. + 206, L. depressa. + + LEPTOCONCHUS. Rüppell. ([Greek: Leptos], _leptus_, thin; [Greek: + Konchos], _conchos_, shell.) This shell resembles a young MAGILUS in + general appearance, although the animal is said to differ. In the young + Magilus also, the inner lip is reflected over the body whorl, which is + not the case in Leptoconchus. Red Sea. Fig. 11. + + LEPTOCONUS. Sw. A sub-genus of Conus, consisting of Conus grandis, + amadis, duplicatus, Australis, &c. Sw. p. 312. + + LEPTOLIMNEA. Sw. A sub-genus of Limnea, described as being nearly + cylindrical. Limnea elongata, Sow. Gen. fig. 6. + + LEPTON. Turton. SOLEN Squamosus, Montague, and other species described + as "flat, nearly orbicular, equivalve, inequilateral, a little open at + the sides. Hinge of one valve with a single tooth, and a transverse + linear lateral one on each side; of the other valve, with a cavity in + the middle and a transverse deeply cloven lateral tooth each side, the + segments of which divaricate from the beak." To represent this genus we + have figured L. Squamosum in the plates, fig. 62. British. + + LEPTOSPIRA. Sw. A sub-genus of Bulinus, thus described: "Spire + excessively long, sub-cylindrical; body whorl largest; outer lip + thickened; aperture oval; no teeth, striata, _Sw._ Chem. 135. f. 1226. + signata _Sw._" Sw. p. 335. + + LEUCOSTOMA. Sw. A genus of "Achatina," Sw. described as resembling + Achatinella, but having a "thick pad" at the top of the "upper lip," + and another over the base. L. variegata, Sw. Lardn. Cyclop. Malac. fig. + 24. p. 172. + + LEUCOTUS. Sw. A sub-genus of Natica, described as intermediate between + Sigaretus and Lacuna. SIGARETUS _cancellatus_, Lam. (Sw. Malac. p. + 346.) + + LICIUM. Humph. OVULA, Lam. (Ovulum.) + + LIGAMENT. (From _Ligo_, to bind.) The true ligament is always external, + and serves the purpose of binding the two valves of a shell together + externally by the posterior dorsal margins. There is another substance, + called by Gray the _Cartilage_, which is elastic and of a condensed + fibrous structure, placed within the ligament, either close to it, or + at a more interior part of the shell; it is sometimes contained in a + pit, formed for its reception, in the centre of the hinge. This + substance, being elastic, keeps the valves open, unless drawn together + by the counteracting force of the adductor muscles. When conchologists + speak of a shell as having the ligament external, the real meaning is + that these two substances are so close together as in appearance to + constitute one body placed outside the shell so as to be seen when the + valves are closed. When two ligaments are spoken of, as in Amphidesma, + the meaning is that the cartilage occupies a separate place on the + hinge. + + LIGAMENTIFEROUS. (_Ligamentum_, a ligament, _fero_, to bear.) Having or + containing the ligament, as the cardinal pit in Mya, fig. 71. + + LIGULA. Leach. A genus containing the more rounded and less gaping + species of LUTRARIA, Auct. Fig. 77, Lutraria Papyracea. + + LIGULATE. (_Ligula_, a slip, a shoe-latchet.) Thin, slender, like a + slip, or neck of any thing, as the anterior muscular impression of + Lucina, fig. 104. + + LIGUMIA. Sw. A sub-genus of Unio, thus described:--"Very long and + pod-shaped; bosses depressed; cardinal teeth moderate. S. recta. Lam. + vi. 1. p. 74." Sw. p. 378. + + LIGUUS. Montf. A genus containing species of ACHATINA, Auct. which have + rounded apertures and lengthened spires, differing from his POLYPHEMI, + which have lengthened apertures. A. virginea, Auct. fig. 286, is the + type of this genus. + + LIMA. Brug. (_Lima_, a file.) _Fam._ Pectinides, Lam. Subostracea, + Bl.--_Descr._ Equivalve, inequilateral, compressed, + oblique-auriculated, oval, radiately ribbed or striated, imbricated, + covered with a light brown epidermis; hinge with a triangular disc + between the umbones, divided in the centre by a triangular ligamentary + pit without teeth; muscular impression one, sublateral, + sub-orbicular.--_Obs._ The shells thus described are marine, two or + three species being found on our coasts, and fossil species occurring + in Lias, inferior Oolite, Calcaire-grossiér, &c. They differ from + Pecten in having a wide hiatus for the passage of a byssus, by which + they are occasionally attached, and also in the triangular disc, which + separates the umbones. The animal makes use of the valves of his shell + as natatory organs, working them like fins or paddles, and by this + means proceeding at a rapid rate through the waters. L. Squamosa, fig. + 174. + + LIMACINA. Cuv. (_Limax_, a snail.) _Fam._ Pteropoda, Lam.--_Descr._ + Papyraceous, fragile, planorbicular, sub-carinated, obliquely + convolute; spiral side rather prominent, the other side umbilicated; + aperture large, entire, not modified, peristome sharp.--_Obs._ This is + SPIRATELLA, Bl. The shell figured as Limacina in Sowerby's Genera, + under "pteropoda," is an _Atlanta_. Our representation of Spiratella + Limacinea, fig. 224. is copied from Blainville. + + LIMACINEA. Lam. A family of the order Gasteropoda, Lam. including the + following + + 1. CRYPTELLA. Spire mammillated; a septum. Fig. 256. + + 2. PARMACELLA. Flat, haliotoid, spiral. Fig. 257, 258. + + 3. TESTACELLUS. Sub-spiral. Fig. 261. + + 4. LIMAX. Incomplete. Fig. 259. + + 5. PLECTROPHORUS. Conical. Fig. 260. + + 6. VITRINA. Heliciform, hyaline. Fig. 262, 263. + + LIMACINEA. Bl. The third family of the order Pulmobranchiata, Bl. + Described as containing shells very variable in form, most frequently + inclining to globular or oval; the apex always obtuse; aperture + variable, but never emarginated. All the Limacinea are phytophagous and + terrestrial. This family answers to the genus Helix of Linnæus and to + the Colimacea of Lamarck, leaving out the Auriculacea. It contains the + genera Succinea, Bulinus, Achatina, Clausilia, Pupa, Partula, Helix, + Vitrina, Testacella, Limacella, Limax. + + LIMAX. _Lam._ Limacinea, Lam. and Bl.--_Descr._ Internal irregular, + sub-quadrate, scutiform, crystalline; apex rounded, indistinct; + epidermis, light brown, thin, extending beyond the margin.--_Obs._ The + shell is placed under the scutellum of the common garden slug. Fig. 25, + L. Antiquorum. + + LIMNACEA. Bl. The first family of the order Pulmobranchiata, Bl. The + shells of this family are described as thin, with the outer lip always + sharp. It contains the genera Limnea, Physa, Planorbis. + + LIMNEANA. Lam. A family of the order Trachelipoda, Lam. containing the + following genera:-- + + 1. LIMNÆA. Spire produced; including _Physa_. Fig. 308 to 310. + + 2. PLANORBIS. Spire orbicular; including _Planaria_. Fig. 311, 312. + + LIMNEA. Lam. ([Greek: Limnas], _limnas_, lacustrine.) _Fam._ Limnacea, + Lam. and Bl.--_Descr._ Oblong, light, thin; spire variable in length, + acute; last whorl large, aperture large, longitudinal, entire; inner + lip spread over a portion of the last whorl; columella forming an + oblique fold; outer lip rounded at each extremity, thin.--_Obs._ These + light horn-coloured shells are common in standing pools, ponds and + ditches, in various parts of Europe. They resemble the Amber shell + (Succinea) in shape, but the animal of the latter is amphibious, and + the shell of a bright amber colour. L. Stagnalis, fig. 308. L. + auricularia, fig. 309. (RADIX, Montf.) The reversed species have been + separated under the name Physa, fig. 310. Other generic names have been + given to other species. + + LINES OF GROWTH. The concentric striæ or lines formed by the edges of + the successive layers of shelly matter deposited by the animal by which + it increases the shell. The outer edge of the aperture is always the + last line of growth. + + LINGUIFORM. (_Lingua_, tongue; _forma_, form.) Tongue-shaped. + + LINGULA. Lam. (Dim. from _lingua_, tongue.) _Fam._ Brachiopoda, Lam. + Palliobranchiata, Bl.--_Descr._ Equivalve, oblong, depressed, thin, + equilateral, gaping and pointed at the umbones, gaping and truncate or + trilobate at the opposite extremities, attached by a fleshy pedicule + fixed to the umbones.--_Obs._ This is the only bivalve shell which is + pedunculated, in which respect it constitutes a singular anomaly. The + ancient writers, seeing the valves separate, placed it in their systems + under the name Patella Unguis. There are several recent species found + in the Moluccas, and some fossils in sandy indurated marl, and in + alluvium of Suffolk. L. Anatina, fig. 219, is so named from its + resemblance to a duck's bill. + + LINGULINA. D'Orb. A genus of microscopic Foraminifera. + + LINTHURIS. Montf. Conch. Syst. 2. 154. A genus of microscopic + Foraminifera. + + LIP. See LABIUM and LABRUM. + + LIPPISTES. Montf. A genus of microscopic Foraminifera. + + LITHODOMUS. Cuv. ([Greek: Lithos], _lithos_, stone; [Greek: Dôma], + _doma_, house.) _Fam._ Mytilacea, Lam.--_Descr._ Transverse, elongated, + cylindrical, equivalve, with the extremities rounded, and the posterior + extremity rostrated; umbones not prominent, terminal; hinge straight, + destitute of teeth; ligament linear, most conspicuous within; muscular + impressions two.--_Obs._ The shells composing this genus differ from + Modiola, not only in the cylindrical form, but also in the circumstance + from which the generic name is derived, i. e. of their living in + stones. Thus, while the form and structure of the shell bring it near + the Mytili or Muscle shells, the habits of the animal cause it to + approach the Lithophagi, or rock-eating molluscs of Lamarck. L. + Dactylus (fig. 161,) is the Mytilus Lithophagus of ancient authors. + + LITHOLEPAS. Bl. ([Greek: Lithos], _lithos_, stone, [Greek: lepas], + _lepas_, rock.) De Blainville's name for LITHOTRYA, Sow. + + LITHOPHAGIDÆ. Lam. ([Greek: Lithos], _lithos_, stone; [Greek: Phagô], + _phago_, eat or gnaw.) A family of the Conchifera Dimyaria, Lam. + consisting of terebrating bivalves, gaping anteriorly, having no + accessary valves; and containing the genera Saxicava, Petricola, + Venerupis, to which are added other genera enumerated in explanation of + figures 91 to 97. Notwithstanding the numerous genera which have been + created, I think that the most convenient arrangement will be to reduce + them to two, thus-- + + 1. PETRICOLA, with distinct cardinal teeth, including, Clothe, + Venerirupis and Coralliophaga. Fig. 91, 92, 97. + + 2. SAXICAVA, without teeth, including Biapholius, Hiatella, + Sphænia, Byssomya, and Thracia. Fig. 93 to 96. + + LITHOTRYA. G. B. Sowerby. ([Greek: Lithos], _lithos_, stone; [Greek: + truo], _truo_, to bore through.) _Fam._ Pedunculated Cirripedes, + Lam.--_Descr._ Eight unequal valves, forming a laterally compressed + cone, the lower central valves being very minute; pedicle fleshy, scaly + at the upper extremity; fixed at the base in a patelliform shelly + support.--_Obs._ This genus derives its name from the power possessed + by the animal of making dwelling holes in stones or pieces of rock. The + remarkable shelly cups at the base of the pedicle is regarded as + analogous to the shelly base of the Balanus, so that this genus would + form an intermediate link between the Sessile and Pedunculated + Cirripedes of Lamarck. Fig. 39, L. dorsalis. West India Islands. + + LITIOPA. Ranz. _Fam._ Turbinacea, Lam.--_Descr._ "Shell not very thick, + horny, with a slight epidermis, rather transparent, conical, with + whorls somewhat rounded; the last being larger than all the rest + together; with the apex pointed, longitudinally grooved; aperture oval, + larger anteriorly than posteriorly, with the lips disunited, the right + lip simple, separated from the left by a rather indistinct notch, or a + slight emargination in the contour. The left lip slightly reflected + backwards, so as to form a kind of salient margin with the anterior + extremity of the columella, which is united, rounded, arcuated and + slightly truncated at the anterior."--_Obs._ The Molluscous animals, + whose shells are thus described, are found in the Mediterranean, and + are remarkable for the power of suspending themselves from the sea-weed + on which they live, by a thread resembling a spider's web. The general + appearance of the shell presents a medium between Phasianella and + Littorina, but it is apparently destitute of an operculum. + + LITTORINA. Fer. (_Littus_, the sea-shore.) _Fam._ Turbinacea, + Lam.--_Descr._ Turbinated, thick; spire acuminated, consisting of few + whorls, about one third of the axis in length; aperture entire, large, + rounded anteriorly; outer lip thickened within, acute; columella rather + flattened; operculum horny, spiral, with rapidly increasing + volutions.--_Obs._ The shells composing this genus are known from Turbo + and Phasianella by the horny operculum; and from Trochus, which has + also a horny operculum, by the small number of the whorls. The + Littorinæ, among which may be enumerated the common Periwinkle, are, as + the name implies, found on sea shores, feeding upon seaweed, in all + parts of the world. Fig. 363, _L. Vulgaris_. + + LITUACEA. Bl. The second family of Polythalamacea. Bl. The shells are + described as chambered, symmetrical, convolute in part of their extent, + but constantly straight towards the termination. The genus Spirula, + which is admitted into this family, does not properly belong to it, any + more than to the Lituolæ of Lamarck, in which it is also placed. It + does not agree with the descriptions of either. This family partly + corresponds with the "Lituolées," Lam. and contains the genera Lituola, + Ichthyosarcolites, Spirula, Hamites and Ammonoceras. + + LITUACEA. Lam. A family of the order Polythalamous Cephalopoda, Lam. + containing the genus Spirula, fig. 471. + + LITUITUS. Montf. SPIROLINA, Lam. Microscopic. + + LITUOLA. Lam. A genus of microscopic Foraminifera. + + LITUOLÆ. Lam. The third family of Polythalamous Cephalopoda, Lam. the + shells of which are described as partially spiral, the last whorl + continuing in a straight line. The transverse septa which divide the + chambers, are in general pierced by a siphon which breaks itself off + before it reaches the succeeding septum. This family contains the + genera of microscopic Foraminifera Lituola and Spirolina. The genus + Spirula, also placed in this family, does not by any means agree with + Lamarck's definitions "the last whorl continuing in a straight line." + + LITUUS. Humph. CYCLOSTOMA? Lam. + + LIVID. (From _lividus_.) Of a pale, dull, blue colour. The adjective is + sometimes used as a specific name. _Ex._ Conus _lividus_, Sanguinolaria + _livida_. + + LOBARIA. Schum. SANGUINOLARIA rosea, Lam. (fig. 98) and other similar + species. + + LOBATE or LOBED. Divided into parts. + + LOBATULA. Fleming. A genus composed of two very minute species of + chambered shells. Serpula lobata and S. concamerata, Mont. Test. Brit. + 515. + + LOMASTOMA. Rafinesque. An imperfectly defined genus, probably belonging + to the Limnacea. + + LONGITUDINAL. Lengthwise. Longitudinal striæ, ribs, &c. are those which + radiate from the apex and follow the spiral direction of the whorls, in + spiral shells; and from the umbo to the ventral margin in bivalves. The + term "decourantes" is employed by French conchologists. The bands in + Achatina, fig. 286, are longitudinal or spiral. + + LORIPEDES. Poli. A genus composed of species of LUCINA, Auct. in which + the lunules are not prominent. + + LOTORIUM. Montf. A genus composed of species of TRITON, Auct. in which + the aperture is effuse. T. Lotorium, fig. 400. + + LOTTIA. Gray. PATELLOIDA, Quoy and Gaimard. + + LUCERNA. Humph. A generic name applied to some species of Helix + included in De Ferussac's sub-genus Helicogena. + + LUCERNELLA. Sw. A genus of "Lucerninæ," Sw. thus described: "Teeth on + both sides of the aperture; surface regularly and distinctly striated. + Circumference convex." + + LUCIDULA. Sw. A sub-genus of Lucerna, Humph. thus described: "Aperture + transverse, both lips much thickened and united; the outer with + marginal obsolete teeth at the base; umbilicus closed. Barbadensis, + _Lam._ No. 49. p. 78. Fêr. Moll. pl. 47, 2, 3, 4." + + LUCINA. Brug. _Fam._ Nymphacea, Lam. Conchacea, Bl.--_Descr._ + Equivalve, inequilateral, orbicular, lenticular, radiately striated; + hinge with, generally, two minute cardinal teeth, which are sometimes + nearly obsolete, and two lateral teeth, on each side of the umbo in one + valve, one in the other; ligament external, partly hidden by the + margins of the valves when closed. Muscular impressions two in each + valve, the anterior one produced into an elongated, ligulate band, the + posterior short and semi-rotund; impression of the mantle not + sinuated.--_Obs._ The shells of this genus resemble Amphidesma in + general form, but are distinguished by the external ligament, the + elongated muscular impression, and the want of a sinus in the palleal + impression. East and West Indies, and European shores. Fig. 104, L. + Tigerina. + + LUNULATE. (_Luna_, the moon, dim.) Moon-shaped, having the form of a + crescent. Applied most frequently to muscular impressions. Semilunar is + sometimes used, perhaps with greater accuracy, to express the same + shape. + + LUNULE. An impression on the anterior dorsal margin of some bivalve + shells. The similar impression on the posterior dorsal margin is called + the _escutcheon_. + + LUPONIA. Gray. A genus composed of species of CYPRÆA, Auct. which are + described as having the anterior of the columellar lip crossed by + several irregular ridges, without any distinct marginal ones, + internally narrow, flat; the shell pear-shaped, smooth, or + cross-ribbed. _Ex._ C. Algoensis, Luponia Algoensis, Gray, fig. 447. + + LUTRARIA. Auct. (_Lutum?_ mud.)--_Fam._ Mactracea, Lam.--_Descr._ Thin, + equivalve, inequilateral, transverse, oblong or ovate, gaping at both + extremities; hinge with one double and sometimes one single cardinal + tooth in each valve, and a triangular, oblique pit with a prominent + margin, containing the ligament; muscular impressions distant; palleal + impression having a large sinus.--_Obs._ This genus differs from Mactra + in the entire absence or indistinctness of lateral teeth. Fig. 77, L. + Papyracea. (Ligula, Leach.) Fig. 78. L. Solenoides. Sandy and muddy + shores. + + LUTRICOLA. Bl. LUTRARIA. Lam. Fig. 77, 78. + + LYCOPHRIS. Montf. A microscopic fossil described as resembling + NUMMULITES, but having a granulated surface. + + LYMNADEA. Sw. A sub-genus of "Mysca," Turton, in the family of Nayades, + Lam. thus described: "Posterior hinge margin elevated and winged; the + valves connate; the surface smooth. L. alata. _Sw._ _Ex._ Conch. (fig. + 48.) fragilis. _Sw._ Zool. Ill. compressa, _Lea._ Am. Tr. iii. pl. 12. + f. 22." Sw. p. 379. + + LYMNEA. See LIMNEA. + + LYMNEUS. Lam. See LIMNEANA. + + LYONSIA. Turt. Inequivalve species of ANATINA, Auct. which have no + spoon-shaped cavity in the hinge, but an accessary piece. L. striata, + fig. 491, 2. + + LYRODON. Goldf. TRIGONIA? + + MACLURITES. Lesuour. Journ. des Scienc. Nat. Philad. t. 1. p. 312. pl. + 13. fig. 2, 3. + + MACOMA. Leach. VENUS tenuis, Bl. and similar species, described as + "Clothed with an epidermis; striated, compressed, oval; the summits not + very prominent; two bifid teeth upon the right valve and a single + undivided one upon the left." + + MACRODITUS. Montf. LENTICULINA, Bl. A genus of microscopic + Foraminifera. + + MACROSPIRA. Guild. A genus composed of HELIX octona, Auct. Macrospira + aperta, Guild. + + MACROSTOMATA. Lam. ([Greek: Makros], _macros_, long; [Greek: stoma], + _stoma_, mouth.) A family belonging to the first section of the order + Trachelipoda, the shells belonging to which are described as haliotoid + or ear shaped, with a very large aperture, destitute of an operculum. + This family contains the following genera, which maybe thus + distinguished. + + 1. VELUTINA. Globose, with velvety epidermis. Fig. 337. + + 2. STOMATIA. Ear-shaped; pearly within; including STOMATELLA. Fig. + 335, 336. + + 3. SIGARETUS. The same, not pearly; including _Cryptostoma_. Fig. + 334. + + 4. CORIOCELLA. The same, thin, transparent. + + 5. HALIOTIS. The same, not thin, nor transparent; with holes; + including _Padollus_. Fig. 338, 339. + + 6. SCISSURELLA. Heliciform, with a slit near the aperture. Fig. + 340. + + 7. PLEUROTOMARIA. Trochiform, with a slit at the edge of the + aperture. Fig. 341. + + MACTRA. Auct. (_Mactra_, a kneading trough.) _Fam._ Mactracea, Lam. + Conchacea, Bl.--_Descr._ Usually thin, equivalve, sub-equilateral, + sub-trigonal, slightly gaping at the extremities; hinge with one + cardinal tooth, divided into two parts, diverging from the umbo, with + sometimes a very small laminar tooth close to its side; a deep + triangular pit near the centre, containing the cartilage; one long, + lateral tooth on each side of the umbo in one valve, received between + two in the other; muscular impressions two, lateral; palleal impression + with a small sinus.--_Obs._ This genus contains many species of + beautiful shells found in various parts of the world, some are common + in Britain. Fossil species are not numerous, they occur in the tertiary + strata. Fig. 79 to 82. + + MACTRACEA. Lam. A family of the order Conchifera Dimyaria, Lam. Sect. + Tenuipedes. The cartilage placed in a trigonal pit with a small + external ligament. The genera may be thus distinguished. + + 1. LUTRARIA. No lateral teeth, shell gaping. The short species + constitute the genus _Ligula_. Fig. 77, 78. + + 2. MACTRA. Lateral teeth, shell closed. This genus has been divided + into Mactra, Mulinia, Schizodesma and Spisula, by Mr. Gray. Fig. 79 + to 82. + + 3. GNATHODON. Teeth serrated, thick, one angular. Fig. 83. + + 4. CRASSATELLA. Shell thick, lateral teeth. Fig. 84. + + 5. AMPHIDESMA. A distinct external ligament, internal ligament + oblique. Fig. 85. + + 6. ERYCINA. A short tooth on each side of the cartilaginous pit in + each valve. Including Mesodesma. Fig. 86. + + 7. UNGULINA. Ligament flat, divided. Fig. 88. + + MACULATED. (From _Macula_, a spot.) Spotted or patched. This term is + applied by conchological writers, to those shells which are coloured in + spots or small patches. In the same sense it is also used as a specific + name. As for instance, Cytherea maculata, fig. 167, c. and Hippopus + maculatus, fig. 156. + + MAGAS. Sow. ([Greek: Magas], _magas_, a board, a deck.) _Fam._ + Brachiopoda, Lam.--_Descr._ Equilateral, inequivalve; one valve convex, + with a triangular area, divided by an angular sinus in the centre; the + other valve flat, with a straight hinge line and two small projections; + a partial longitudinal septum, with appendages attached to the hinge + within. Differing from Terebratula in having a triangular disc, and not + a circular perforation. Magas pumilus, fig. 299. Fossil in chalk. + + MAGILUS. Montf. _Fam._ Cricostomata, Bl. Serpulacea, Lam.--_Descr._ + Thick, tubular, irregular, contorted; rounded above, keeled beneath, + free; apicial extremity convolute, heliciform, ovate or sub-globose; + aperture elliptical.--_Obs._ This shell when in a young state presents + the characteristics of a regularly formed spiral univalve, living in + holes in madrepores. As the madrepore increases in bulk, the animal + gives an eccentric course to the shell, in order to have its aperture + even with the surface, and leaving the nucleus or young shell behind, + fills it up with calcareous matter to reside in the open extremity of + the tube. Fig. 9, 10. Red Sea and Mauritius. + + MALACOTA. Schum. OTION. Leach. + + MALACOZOA. Bl. ([Greek: Malakos], _malacos_, soft; [Greek: Zôon], + _zoon_, animal.) The type or general appellative in De Blainville's + system, including all molluscous animals, excepting those with + multivalve shells. + + MALDANIA. Lam. The second family of the order Annelides Sedentaria. The + only genus of shells described in this family is Dentalium, fig. 2, to + which may be added Pharetrium, König. fig. 3. It is doubtful however + whether the latter do not belong to an unknown genus of Pteropodous + Mollusca. + + MALEA. Valenciennes. A genus composed of DOLIUM latilabrum, Kiener, and + other similar species. + + MALENTOZOA. Bl. ([Greek: Malakos], _malacos_, soft; [Greek: en], _in_, + [Greek: temnô], _temno_, cut; [Greek: Zôon], _zoon_, animal.) Or + articulated mollusca. The sub-type in De Blainville's system, + comprehending those with multivalve shells. + + MALLEACEA. Lam. A family belonging to the order of Conchifera + Monomyaria. Containing the following genera of irregular pearly + bivalves. + + 1. AVICULA. Hinge linear, simple, including _Meleagrina_. Fig. 163, + 164. + + 2. PERNA. Hinge with linear grooves, including _Pulvinites_. Fig. + 166, 170. + + 3. GERVILLIA. Shaped like Modiola, with irregular grooves. Fig. + 162. + + 4. CRENATULA. Hinge with a series of pits. Fig. 168. + + 5. CATILLUS. Like Perna, but more regular and convex. Fig. 167. + + 6. MALLEUS. A triangular disc on the hinge, and two auricles. Fig. + 165. + + MALLEUS. Auct. (_Malleus_, a hammer.) _Fam._ Malleacea, Lam. + Margaritacea, Bl.--_Descr._ Equivalve, inequilateral, foliaceous, + trilobate, undulated, irregular, attached by a byssus passing through a + sinus in one valve; hinge rectilinear, lengthened by two auricles; with + a small disc under the umbones, containing the ligament, and a groove + containing the cartilage; muscular impressions one in each valve, + large, uniform, and one or two others extremely minute.--_Obs._ Malleus + Vulgaris, the type of this genus, is a most singular shell, commonly + called the "Hammer Oyster," from the peculiarity of its shape. It + belongs to the Linnæan genus Ostrea, from which it differs in being + attached by a byssus. Fig. 165, M. Vulgaris. Tropical. + + MAMILLARIA. Sw. A sub-genus of NATICA, corresponding with Polinices of + Montfort, having the spire small and the umbilicus filled. _Ex._ Natica + Mamilla, Auct. fig. 327. + + MAMMILLATED. (_Mammula_, a little teat.) A term applied to the apex of + a shell when it is rounded like a teat. _Ex._ Voluta Vespertilio, fig. + 433. + + MARGARITA. Leach. (_Margarita_, a pearl.) A genus of small shells + resembling the genus Trochus, from which it differs in having an + operculum consisting of few whorls. M. tæniata, fig. 362. Mr. G. B. + Sowerby, sen. has enumerated 15 species in a list accompanying the + figures published by the author of this manual in Nos. 132 to 134 of + his Conchological Illustrations. + + MARGARITACEA. Bl. The third family of Lamellibranchiata, Bl. The shells + belonging to it are described as irregular, inequivalve, inequilateral, + black or horny without, pearly within; hinge auriculated, scarcely + developed, and without teeth. The ligament is variable and there is a + large sub-central muscular impression. This family contains the genera + Vulsella, Malleus, Pinna, Crenatula, Inoceramus, Catillus, Pulvinites, + Gervillia and Avicula. + + MARGARITACEOUS. (_Margarita_, a pearl.) Pearly. + + MARGARITANA. Schum. A sub-genus of Uniones, composed of species having + "one cardinal tooth." ALASMODON, Say. MYA Margaritifera, Linn. + + MARGARITIFEROUS. (_Margarita_, pearl; _fero_, to bear.) Pearl-bearing. + Applied to shells which form pearls; as Meleagrina Margaritifera, or + Pearl-bearing Oyster. + + MARGINAL. Near the margin or edge. + + MARGINATED. (_Margo_, edge.) Having an edge or border thicker than the + rest of the shell, from which circumstance the little genus Marginella + derives its name. + + MARGINELLA. (A little rim or border.) _Fam._ Columellaria, Lam. + Angyostomata, Bl.--_Descr._ Ovate, smooth, shining, with a short, + sometimes hidden spire; aperture narrow, emarginated; columella with + several oblique folds; outer lip neatly reflected.--_Obs._ This genus + of pretty little shells differs from Voluta, in the reflection of the + outer lip. The animal covers the greater part of the shell with the + mantle, and by continually depositing vitreous matter gives it a bright + polish, which, together with the delicately neat arrangement of colours + in most species, renders them exceedingly beautiful. The Marginellæ are + marine and tropical. A few fossil species are found in the + Calc-grossier. Fig. 437. M. Glabella. GLABELLA, Sw. + + MARGINULINA. D'Orb. A genus of microscopic Foraminifera. + + MARINE CONCHACEA. See CONCHACEA. + + MARINE TESTACEA. Those shell-fish which inhabit seas, lakes, &c. of + salt water, in distinction from the _Aquatic_ Testacea, or those which + are found in rivers, ponds or stagnant pools of fresh water: and also + from the _Land_ Testacea, which live on land and breathe air. The great + proportion of shells belong to the former class, those of the latter + two classes being limited in their number, and in the genera to which + they belong. + + MARINULA. King. A genus of small shells resembling Auricula and + Pedipes, described as "Ovate, sub-solid, with aperture ovate entire; + columella bidentate, uniplicated towards the base, with large + sub-remote teeth; the largest uppermost; no operculum." + + MARMAROSTOMA. Sw. A genus of "Trochidæ," Sw. thus described: "Umbilicus + deep; spire of few whorls, much depressed, and obtuse; inner lip + obsolete; base even more produced than in _Senectus_, but never + distinctly channeled. M. versicolor. Mont. 176. f. 1740, 1741, + undulata. Chem. 169. f. 1640, 1641," Sw. p. 348. + + MARPESSA. Gray. A sub-genus of Clausilia, C. bidens, &c. Auct. Gray's + Turton, p. 212. + + MARTESIA. Leach. A genus composed of those species of PHOLAS, Auct. + which are described as short, cuneiform, nearly closed at both + extremities, having several accessary pieces on the middle of the back, + and two marginal, lower down. + + MEASUREMENT. The most approved method of stating the measurements of + various kinds of shells is as follows: _symmetrical convolute + univalves_, the length is from anterior to posterior; the depth from + ventral to dorsal; the breadth, from side to side of the aperture. Of + _symmetrical conical univalves_, length, from front to back; breadth + from side to side; depth from apex to base. Of _spiral univalves_, + length, from apex to anterior of the columella or axis of the shell; + breadth, across from the outer lip to the opposite side. Of + _non-symmetrical bivalves_, the length is from the anterior to the + posterior margin; breadth, from the greatest convexity of one valve to + the corresponding part of the other; depth, from the ventral to the + dorsal margin. + + MEGADESMA. Bowd. ([Greek: Megas], _megas_, great; [Greek: desma], + _desma_, ligament.) POTAMOPHILA, Sow. GALATHÆA, Lam. + + MEGADOMUS. Sw. A sub-genus of Unio, thus described: "Only one lateral + tooth in each valve; cardinal teeth two; posterior hinge margin winged. + M. gigas, _Sw._" Sw. p. 378. + + MEGALODON. Sow. ([Greek: Megas], _megas_, great; [Greek: odos], _odos_, + tooth.) _Fam._ Cardiacea, Lam.--_Descr._ Equivalve, longitudinal, + acuminated at the umbones, thick; hinge forming an incrassated septum + across the cavity of the shell, with a large bifid tooth in the right + valve, and one irregular and one pointed in the left; ligament long, + external.--_Obs._ The general form, the thickened hinge reaching across + the cavity of the valve and the terminal umbones serve to distinguish + this genus from Cardita, to which, however, it is nearly allied. M. + cucullatus, fig. 127. + + MEGALOMASTOMA. Guild. A sub-genus of Cyclostoma, thus described: + "Cylindrical, resembling _Pupa_, but has a horny operculum; spire not + thickened; teeth or fold on the pillar none, flavula _Sw._ En. Méth. + 461. f. 6, brunnea _Guild._ (_fig. 97. g. h. 1._)" Sw. p. 336. Mr. Gray + applies the name to those species which have "a groove or ridge in + front of the mouth near the pillar." + + MEGARIMA. Rafinesque. A genus proposed to include species of + TEREBRATULA, Auct. which are smooth and nearly equivalve. T. lævis, T. + crassa, T. truncula. + + MEGASPIRA. Lea. ([Greek: Megas], _megas_, great, and spire.) M. + Ruschenbergiana, (fig. 294) is a pupiform land shell remarkable for the + length of its spire, which consists of no less than twenty-five close + set, narrow, gradually increasing whorls. The outer lip is simple, + slightly thickened; the inner lip has a tooth on the body-whorl, and + two folds on the columella. Only one species of this singular shell is + known. + + MEGATREMA. Leach. A genus composed of those species of Pyrgoma, Auct. + which have a large aperture. Fig. 33. + + MELACANTHA. Sw. A sub-genus of Melania. Sw. p. 341. + + MELAFUSUS. Sw. A sub-genus of Melanopsis. Sw. p. 341. + + MELAMPUS. Montf. CONOVULUM, Lam. A genus composed of species of + AURICULA, Auct. of a conical form. A. conoidalis, fig. 298. + + MELANIA. Auct. ([Greek: Melas], _melas_, black.) _Fam._ Melaniens, Lam. + Ellipsostomata, Bl.--_Descr._ Turrited; spire generally elongated, + acute; aperture entire, oval or oblong, pointed at the posterior + extremity, rounded anteriorly, with a kind of indistinct canal or + sinuosity: epidermis thick, generally black.--_Obs._ In common with + other fresh-water shells, the Melaniæ are frequently found with + corroded apices. This genus is known from Melanopsis by the absence of + the notch at the anterior part of the aperture. The Melaniæ occur in + rivers of warm climates. The fossil species are frequent in upper + marine formations. Fig. 313, M. subulata. + + MELANIANA. Lam. (Melaniens.) A family belonging to the first section of + the order Trachelipoda. The genera contained in it maybe distinguished + as follows. + + 1. MELANOPSIS. Aperture notched; columellar lip thickened above; + including _Pirena_. Fig. 315, 316. + + 2. MELANIA. Aperture not notched; columellar lip not thickened; + including _Auculosa_, _Pasithæa_, _Io_. Fig. 313, 314, 317. + + MELANITHES. Sw. A sub-genus of Melanopsis. Sw. p. 341. + + MELANOIDES. Olivier. MELANOPSIS. Fer. + + MELANOPSIS. Fer. _Fam._ Melaniana, Lam. Entomostomata, Bl.--_Descr._ + Oval or oblong, fusiform; spire acute, sometimes elongated; aperture + oblong or oval, pyriform, with a distinct notch at the anterior + extremity; columella tortuous, callous, thickened at the extremity near + the spire; epidermis thick, horny, generally black. + Subtropical.--_Obs._ This description includes the two first species of + the genus Pirena, Lam. The Melanopsides are known from the Melaniæ by + the notch in the aperture. Fig. 315. M. costata. + + MELAS. Montf. MELANIA, Auct. + + MELATOMA. Sw. A sub-genus of Melanopsis. Sw. p. 341. + + MELEAGRINA. Lam. MARGARITA. A genus composed of the Pearl Oyster and + similar species, separated from Avicula on account of the roundness of + their general form, but re-united by Sowerby. For generic characters, + see Avicula. Fig. 164. M. margaritifera. + + MELEAGRIS. Montf. TURBO Pica, Auct. and similar species, having the + aperture oblique, the columella gliding imperceptibly into the outer + lip, and having an umbilicus. + + MELINA. Schum. PERNA, Auct. + + MELO. Brod. (_Melo_, a melon.) _Fam._ Columellaria, Lam.--_Descr._ + Light, ventricose, oval, with a light greenish brown epidermis, spire + short, papillary, regular, sometimes hidden by the last whorl; aperture + large, nearly as long as the whole shell, emarginated anteriorly; outer + lip thin; columella slightly curved, with four or five laminar, + oblique, prominent plaits.--_Obs._ The genus Melo has been separated + from _Voluta_ principally on account of the largeness of the aperture, + the lightness of the shell and the thinness of the outer lip. Melo + differs from Cymba in the regularity of the spiral apex, and in the + greater rotundity of the shell. The Melons are beautifully coloured + large shells, found in the seas of the old world. The Melo Indicus has + a certain resemblance to a Melon. Fig. 435. M. Æthiopicus. + + MELONIA or MELONITES. A genus of microscopic Foraminifera. + + MERCENARIA. Schum. VENUS Mercenaria, Auct. The Money shell which passes + current for cash, under the name "Wampum," among the North American + Indians. + + MERETRIX. Lam. Original name for Cytherea, Lam. + + MEROE. Schum. CYTHEREA Meroe, sulcata, scripta, hians, Auct. and + similar species. Fig. 117, a. + + MESODESMA. Desh. ERYCINA, Lam. according to G. B. Sowerby. + + MESOMPHYX. Rafinesque. A genus proposed to be separated from HELIX, + Auct. + + MICROTOMA. Sw. A genus of "Purpurinæ," Sw. thus described, "Pillar very + broad and curving inwards; aperture effuse; the notch at the base small + and nearly obsolete; spire very short, patula. Mart. 69. f. 758, 759. + persica. En. Méth. 397. f. 1. unicolor. _Sw._ Chem. f. 1449. Sw. p. + 301." Purpura Persica. Fig. 414. + + MILIOLA. Lam. A genus of microscopic Foraminifera. + + MISILUS. Montf. A genus of microscopic Foraminifera. + + MITRA. Lam. (_Mitre._) _Fam._ Columellaria, Lam. Angyostomata; + Bl.--_Descr._ Oblong, thick, covered with a light brown epidermis; + spire long, turrited, acute; aperture emarginated anteriorly; outer lip + thickened; columella with several oblique, thick plaits.--_Obs._ The + pretty small shells composing this genus differ from Marginella, not + only in general form, but in the outer lip not being reflected. Some + species of Voluta, of a more elongated shape than the rest, present a + near approach to the most ventricose of the Mitræ. The apex of Mitra, + however, is always acute, while that of Voluta is generally papillary. + The aperture of the former is narrow and the inner lip thickened, the + contrary being the case with the latter. The shells of this genus are + varied in colouring which is generally rich; and also in form, some + being angulated, some plicated, some coronated and others smooth. The + species are mostly tropical; very few occur so far north as the + Mediterranean. Fossil species are numerous in the Eocene beds. Fig. + 431. M. Plicaria. Fig. 432. Conohelix marmorata, Sw. + + MITRELLA. Sw. A genus consisting of MITRA Fissurella, casta, + Olivæformis, and similar species, described as "Rather small; + olive-shaped; unequally fusiform; always smooth and polished, and + sometimes covered with an epidermis; base obtuse and effuse; spire + nearly or quite equal to the aperture; plaits of the pillar few, + oblique, and extending beyond the aperture, which is smooth + internally." Sw. p. 321. M. Fissurata, E. M. 371. f. 1. Olivarii, f. 2. + Dactylus. 372. f. 5. _Ex._ Mitra bicolor. + + MITREOLA. Sw. A genus of "Mitranæ," Sw. thus described: "Small; + unequally fusiform; the base obtuse; inner lip, typically thickened, + inflected, and either toothed or tuberculated; plaits on the pillar + distinct, the inferior largest; tip of the spire sometimes papillary; + aperture without either striæ or groove." Sw. p. 320, M. Monodonta, M. + Terebellum. Zool. Illustr. II. 128. f. 1. f. 2. + + MODIOLA. Lam. (_Modiola_, a little measure.) _Fam._ Mytilacea, + Lam.--_Descr._ Equivalve oblique, cuneiform, inequilateral, thin, with + the anterior side short and narrow, slightly gaping to admit the + passage of a byssus, and the posterior side elongated, broad, + sub-quadrate; hinge thin, toothless, rectilinear, with a long, partly + external ligament; muscular impressions two in each valve; palleal + impression irregular, not sinuated.--_Obs._ This genus differs from + Mytilus, to which the common muscle belongs, in the anterior margin + being rounded out beyond the umbo, which in Mytilus is terminal. The + Lithodomi may be known from this genus by their cylindrical form. Fig. + 160, M. Tulipa. + + MOLLUSCA. (From _Mollis_, soft.) The twelfth class of invertebrated + animals with univalve shells or none; divided into the following + orders: Pteropoda, Gasteropoda, Trachelipoda, Cephalopoda, Heteropoda, + fig. 220 to 488. The term mollusca is also used in a general sense to + include the classes Conchifera and Mollusca of Lamarck, corresponding + with the type Malacozoa of De Blainville. + + MONEY COWRY. Cypræa Moneta, which passes current in some parts of + Africa and the East Indies. + + MONILEA. Sw. A sub-genus of Monodonta. Sw. p. 352. + + MONOCEROS. ([Greek: Monos], _monos_, single; [Greek: Keras], _ceras_, + horn.) _Fam._ Purpurifera, Lam.--_Descr._ Ovate, thick, covered with a + brown epidermis; spire short, consisting of few whorls; aperture + emarginated anteriorly; columella rather flat; outer lip thick, with a + prominent tooth near the extremity.--_Obs._ This genus resembles + Purpura, in every respect, except in having the tooth from which the + name is derived. A catalogue of 16 species by Mr. Sowerby, sen. is + published with figures of 14, in parts 58 to 67 of the Conchological + Illustrations by the author. The species belong to the South American + coasts of the Pacific Ocean. + + MONOCONDYLÆA. D'Orb. A sub-genus of Uniones, described as equivalve, + inequilateral, sub-rotund or angulated; hinge consisting of a large, + obtuse, round cardinal tooth in each valve, with no lateral teeth. + Monocondylæ (Unio) Paraguayana, D'Orb. fig. 149. + + MONODONTA. Lam. ODONTIS, Sow. A genus separated from Trochus, Auct. on + account of the tooth or notch with which the columella abruptly + terminates. M. labeo, fig. 366. + + MONOICA. Bl. The second sub-class of the class Paracephalophora, Bl. + divided into the orders Pulmobranchiata, Chismobranchiata, + Monopleurobranchiata, in the first section; and Aporobranchiata, + Polybranchiata, Cyclobranchiata, Inferobranchiata, and + Nucleobranchiata, in the second. + + MONOMYARIA. Lam. ([Greek: Monos], _monos_, single; [Greek: muon], + _myon_, muscle.) The second order of Conchifera, consisting of those + bivalve shells which have but _one_ principal muscular impression in + each valve. The Monomyaria are thus divided: First section, containing + the families Tridacnacea, Mytilacea, Malleacea; second section, + containing the families Pectinides, Ostracea; third section, containing + the families Rudistes, Brachiopoda. + + MONOPLEUROBRANCHIATA. Bl. The second order of the first section of + Paracephalophora Monoica. Bl. The animals are described as having the + lungs branched, situated at the right side of the body and covered more + or less completely by the operculiform mantle, in which there is + sometimes enveloped either a flat or a more or less involute shell, + with a large entire aperture. They have either rudimentary or auricular + tentacula, or none. This order, which includes mollusca with haliotoid + or patelliform shells, is divided into the following families: _Fam._ + 1. Subaplysiacea; 2. Aplysiacea; 3. Patelloidea; 4. Acera. + + MONOPTYGMA. Lea. A genus of small shells resembling Tornatella, but + having a strong, oblique fold in the centre of the columellar lip. M. + Elegans, fig. 344. + + MONOTHALAMIA. ([Greek: Monos], _monos_, single; [Greek: thalamos], + _thalamos_, chamber.) The second division of Cephalopoda, Lam. + containing only one genus, namely Argonauta. + + MONOTHYRA. A term used by Aristotle to designate spiral univalves. + + MONOTIGMA. Gray. A genus founded on the species represented fig. 371. + It is a turrited shell, but we are unacquainted with the characters of + the genus. + + MORIO. Montf. CASSIDARIA, Auct. C. Echinophora, fig. 407. + + MOTHER OF PEARL. This beautiful substance, which is so much resorted to + for ornamental purposes, constitutes the thickened coating of the + internal surface of the shell named by scientific collectors, + Meleagrina Margaritifera, commonly called the Pearl Oyster, a young + specimen of which is figured (164) in our plates. The reason why this + substance is called mother-of-pearl is that the true pearls are + produced from its surface. They arise principally from accident or + disease, and are sometimes artificially produced by pricking through + the outside of the shell while the animal is living. The animal is + allowed to live until it has formed a pearl over the wounded part. + + MOULINSIA. Grateloup. PUPINA, Vignard. A genus of small land shells + with enamelled surface and spiral operculum. See PUPINA. + + MOURETIA. Gray. "_Gadin_," Adanson. A genus of patelliform shells, + described as differing from SIPHONARIA (the original Mouretia of + Adanson) in the situation of the siphon, which in Mouretia is close to + the place where the muscular impression is interrupted to leave a space + for the head; while in Siphonaria it is nearly half way between the + anterior and posterior ends of the shell. + + MOUTH. The aperture or opening of univalve shells. + + MULINIA. Gray. A genus composed of species of MACTRA, Auct. described + as having the ligament (properly so called) internal, and lateral teeth + simple. _Ex._ fig. 82. M. bicolor; Mactra, Auct. + + MULLERIA. Fer. _Fam._ Ostracea, Lam.--_Descr._ Irregular, subquadrate, + inequivalve, inequilateral, foliaceous, attached, pearly within, green, + horny without; hinge irregular, with a partly external ligament, + passing to the interior, through a sort of sinus.--_Obs._ This + remarkable shell resembles Etheria in general form and appearance, but + is distinguished by having only one muscular impression. It is so rare + that, although not very beautiful, a specimen has been known to produce + £20. at a sale. Fig. 192. + + MULTILOCULAR. Many chambered. + + MULTISPIRAL. (_Multus_, many, _spira_, spire.) A term applied to a + shell when the spire consists of numerous whorls; or to an operculum of + numerous volutions. + + MULTIVALVE. (_Multus_, many; _valva_, valve.) Consisting of numerous + valves. There are three kinds of multivalve shells: 1st. Those in which + the valves are arranged in pairs, and produce a flattened figure, as + Pedunculated Cirripedes, fig. 34 to 43; 2nd. Those in which they are + arranged circularly, as Sessile Cirripedes, the valves of which are of + two kinds; the _opercular_, consisting of several valves, which close + the aperture, and the _parietal_, consisting of those which surround + the body of the animal in a circular form, fig. 14 to 33. 3rd. Those in + which they are arranged in a straight line, as Chiton, fig. 227. + + MUREX. Auct. (_A sharp rock._) _Fam._ Canalifera, Lam. siphonostoma, + Bl.--_Descr._ Turrited, ventricose, thick, with three or more + longitudinal, continuous, branched, spinose or fringed varices; spire + prominent, acute; aperture oval, terminating in a posterior, partly + closed canal, outer lip varicose, inner lip smooth, laminar; operculum + horny, concentric, pointed.--_Obs._ This genus contains some of the + most exquisitely beautiful shells in existence, the richness of their + colouring, the ramifications of their varices, would render most + species the finest possible subject for the exercise of the painter's + art in still life. The most remarkable are the Rosebud Murex, with its + pink-tipt fringes, the Venus Comb, with its long rows of parallel + spines; the Ducal Murex, the Royal Murex, and many others, which are + much sought after by collectors. Murex may be distinguished from Triton + by the continuity of the varices, which follow each other in a tortuous + direction on the spire. The Ranellæ have only two rows of varices, and + have a posterior as well as anterior canal; while Murices have three or + more varices, and only one canal. The genus Typhis consists of several + small species resembling Murex in every respect, excepting that of + having a tubular opening on the upper part of the whorl between each + varix. See TYPHIS. The most beautiful Murices are brought from tropical + climates. Fig. 395, 396. + + MURICANTHUS. Sw. A sub-genus of Murex, thus described: "Varices + numerous, foliated; spire short; margin of the outer lip with a + prominent tooth near the base; Radix. _Sw._ Zool. Ill. 2nd series. pl. + 113, Melanomathus. En. Méth. 418. f. 2." Sw. p. 296. The latter of the + two species quoted, however, does not agree with the description, + having no prominent tooth on the margin of the outer lip. + + MURICATED. (_Muricatus._) Having sharp points or prickles. + + MURICIDEA. Sw. A genus of "Muricinæ," Sw. thus described, "Spire more + produced, as long or longer than the body whorl; varices numerous; no + internal channel at the top of the aperture." Sw. p. 297, and + consisting of the following incongruous species, "Lamellosa. Chem. f. + 1823, 4. magellanica. En. M. 419. f. 4. peruviana. Ib. f. 5. senticosa, + Ib. f. 3. scaber. En. Méth. 419. f. 6. hexagona. Ib. 418. f. 3. + erinacea. Mart. f. 1026." Sw. p. 297. + + MUSCULAR IMPRESSIONS are the marks or areas formed on the interior + surface of shells by the muscular fibres which attach the animals to + them. Lamarck has divided his Conchifera into two kinds: 1st. + Monomyaria, those which have but one adductor muscle, and consequently + have but one impression in each valve, as the common Oyster, fig. 180; + 2nd. The Dimyaria, those which have two, and consequently have two + impressions in each valve. There are other smaller impressions in some + shells besides the principal. The palleal impression is a mark or scar + passing near the margin of the shell. See Introduction. + + MYA. Auct. _Fam._ Myaria, Lam. Pyloridea, Bl.--_Descr._ Transverse, + oval, thick, gaping at both extremities, rounded anteriorly, acuminated + posteriorly; hinge with one large, dilate, compressed tooth in one + valve, and a suture in the other, containing the cartilage; muscular + impressions two, distant, large, irregular; palleal impression with a + large sinus.--_Obs._ Mya may be known by the large, prominent, broad + tooth in one valve. In Anatina there is one in each valve, and, in + Lyonsia, accessory pieces. Lutraria has cardinal teeth and a + ligamentary pit. Few species of Mya are known. They belong to the + Northern Hemisphere. M. truncata, fig. 71. + + MYCETOPODA or MYCETOPUS. D'Orb. _Fam._ Nayades, Lam.--_Descr._ Shell + elongated, soleniform, inequivalve, inequilateral, gaping anteriorly; + muscular impressions very complex.--_Obs._ These shells are said to + terebrate like Pholas. Fig. 151. M. solenoides. + + MYARIA. Lam. A family belonging to Lamarck's order Conchifera Dimyaria. + Containing the following genera: + + 1. ANATINA. Ligament in a spoon-shaped prominence on the hinge of + each valve, shell thin. Fig. 69. + + 2. MYA. Spoon-shaped prominence in one valve; shell thick. Fig. 71. + + 3. ANATINELLA. A spoon-shaped process in both valves. Fig. 70. + + 4. LYONSIA. An internal bony appendage on the hinge. Fig. 491, 492. + + 5. MYOCHAMA. Flat valve attached, a bony appendage on the hinge. + Fig. 73. + + 6. CLEIDOTHÆRUS. Deep valve attached, a bony appendage. Fig. 75, + 76. + + 7. CUMINGIA. Ligamentary pit in both valves, spoon-shaped. Fig. 87. + + MYOCHAMA. Stutch. (_Mya_ and _Chama_.) _Fam._ Myaria, Lam.--_Descr._ + Inequivalve, irregular, attached, subequilateral; attached valve flat, + with two marginal, diverging teeth, and one end of a little testaceous + appendage fixed between them by a horny cartilage; free valve convex, + with umbo incurved and two very minute, diverging teeth, between which + the other end of the testaceous appendage is placed; external surface + of both valves conforming to the grooves or undulations of the shell to + which the specimen is attached; muscular impressions two in each valve; + palleal impressions with a short sinus.--_Obs._ This new genus, of + which only one species is known, the M. anomioides from New South + Wales, differs from Anomia and Anatina in being attached by the surface + of one of the valves, from which circumstance the word Chama is added + to its name; the little testaceous appendage bringing it near the + Myariæ. Fig. 73, M. anomioides. + + MYOCONCHA. Sow. (_Mya_ and _Concha_.) _Fam._ Cardiacea, Lam.--_Descr._ + Oval, equivalve, oblique; umbones terminal; ventral margin rounded; + hinge with an external ligament, and one oblique, elongated tooth in + the left valve; impression of the mantle not sinuated.--_Obs._ The + fossil genus has the general form of Mytilus or Modiola, but the hinge + of the Conchæ generally. + + MYOPARA. Lea. (_Myoparo_, a piratical oar-galley.) _Fam._ Arcacea, Lam. + A genus founded on a minute fossil bivalve shell, somewhat resembling + Isocardia in form, but having a series of teeth placed on each side of + the umbones. M. costatus, fig. 135. + + MYRISTICA. Sw. A genus of "Pyrulinæ," Sw. thus described: + "Sub-pyriform; spire strong, spiny, or tuberculated, nearly as long as + the base; umbilicus either partially or entirely concealed; inner lip + vitreous, thin; the outer with an internal and ascending canal; the + basal channel wide. Hippocastanea. En. M. 432. f. 4. lineata, Ib. f. 5. + melongena. En. Méth. 435. f. 3. nodosa. Chem. 1564. 5." Sw. p. 307. + _Ex._ P. Melongena, Fig. + + MYRTEA. Turt. VENUS spinifera, Auct. LUCINA spinifera, Nonnull. The + shells of this genus are described as "Oval, triangular, equivalve, + nearly equilateral, closed. Hinge of one valve with a single tooth, and + lateral one on each side; of the other valve with two teeth, the + lateral ones obscure. Ligament external." British Channel and + Mediterranean. + + MYSCA. Turt. A genus composed of species of UNIO, Auct. which are + distinguished by having "strong, transverse, notched, cardinal and long + lateral teeth." Unio pictorum. + + MYSIA. Leach. A genus composed of TELLINA rotundata, montagu and other + similar species. + + MYTILACEA. Bl. The fourth family of Lamellibranchiata, Bl. The shells + are described as regular, equivalve, frequently with a thick, horny + epidermis. A toothless hinge and a linear ligament. This family + contains the genera Mytilus and Pinna. + + MYTILACEA. Lam. A family belonging to the first section of Conchifera + Monomyaria, Lam. described as having the ligament partly interior, + occupying the greater part of the hinge line, which is straight. The + shell is rarely foliaceous. The Mytilaceæ cannot easily be confounded + with the Malleaceæ, because the former are generally regular and the + latter are irregular, and have a thick internal coating of pearl, + beyond which the external coating extends. The genera may be thus + distinguished: + + 1. MYTILUS. Umbones terminating in a point. Fig. 158. + + 2. DREISSINA. The same, with a septiform plate. Fig. 159. + + 3. MODIOLA. Anterior margin rounded beyond the umbones. Fig. 160. + + 4. PINNA. Open at the posterior extremity. Fig. 162. + + 5. LITHODOMUS. Cylindrical, living in holes. Fig. 161. + + MYTILUS. Auct. _Fam._ Mytilacea. Lam.--_Descr._ Equivalve, cuneiform, + oblique, smooth, with umbones terminal, pointed, and posterior side + broad, rounded; hinge linear, with a long, partly internal ligament; + muscular impressions two in each valve, that on the posterior side + large, irregular; that on the anterior small; palleal impression + irregular.--_Obs._ The Linnean genus Mytilus included the Modiolæ, + which differ from the Mytili in the rounded anterior side; and the + Pinnæ, which are large shells, gaping at the posterior extremity. M. + achatinus, fig. 158. + + NÆARA. Gray. A genus composed of ANATINA longirostrum, Lam. and other + similar species. + + NAIA. Sw. A sub-genus of Castalia, Lam. thus described: "Oval, cardinal + teeth beneath the bosses, and deeply sulcated, C. corrugata. _Lam._ En. + Méth. 248. f. 8, picta. _Sw._ En. Méth. 248. f. 6." Sw. p. 379. + + NANINIA. Gray. A genus composed of the planorbicular species of HELIX, + with large umbilici, and outer lip thin, included in the sub-genus + Helicella, Fer. _Ex._ H. citrina, fig. 280. + + NASSA. Lam. A genus of small shells united to Buccinum by some authors, + but separated by others on account of the little tooth-like projection + terminating the columella. N. arcularia, fig. 423. + + NATICA. Brug. _Fam._ Neritacea, Lam. Hemicyclostomata, Bl.--_Descr._ + Globose, thick, generally smooth; spire short, pointed, with few + volutions; aperture semilunar, entire; outer lip thin; columellar lip + oblique, nearly straight, callous; umbilicus with a spiral callosity, + terminating behind the columella, and sometimes filling up the cavity; + operculum shelly in some species, horny in others; epidermis thin, + light, semitransparent.--_Obs._ The straight, callous, smooth edge of + the columella and the callosity serve to distinguish this genus from + Nerita, Neritina, Neritopsis and Helix. Fig. 327, 328. + + NATICARIA. Sw. A sub-genus of Natica, thus described: "Oval; convex + above; umbilicus small, open, placed very near the top of the aperture; + inner lip reflected; small. N. melanostoma, Mart. 189. f. 1926, 1927. + cancellata, _Sw._ Ib. 189. f. 1939. bifasciata, Griff. Cuv. 1. f. 2." + Sw. p. 346. + + NATICELLA. Guild. A sub-genus of Natica, thus described: "Operculum + horny; shell globose, but generally depressed; umbilicus nearly filled + up by a vitreous deposition of the inner lip; spire obtuse. N. + aurantia. Mart. 189. f. 1934, 1935." Sw. p. 345. + + NAVICELLA. Lam. (_A little ship._) _Fam._ Neritacea, Lam. + Hemicyclostomata, Bl.--_Descr._ Transversely oval, symmetrical, smooth; + aperture entire, oval; dorsal surface convex; outer lip thin; inner lip + flat, straight edged; spread over the front surface of the body whorl, + and sometimes hiding the apex; apex incurved; operculum testaceous, + flat, sub-quadrate, with a lateral articulation.--_Obs_. This well + known genus, of which there are several species, is named Cimber by + Montfort. The shells are brought from India, the Isle of France and the + Moluccas. Fig. 323, N. elliptica. + + NAUTELLIPSITES. Parkinson. A generic name proposed to include such + species of Nautilus as have been compressed, so as to assume an oval + instead of a round form. The genus Ellipsolites of De Montfort consists + of species of Ammonites similarly deformed. + + NAUTILACEA. Bl. The fifth family of Polythalamacea, Bl. the shells of + which are described as more or less discoidal, compressed, + symmetrically convolute; the last whorl much longer than the others; + which are entirely hidden beneath it and advancing beyond the last but + one, so as constantly to form a large oval aperture, which is always, + however, modified by the last whorl. The septa are united in the + greater number of instances and pierced by one or more (?) siphons. + This family contains the genera Orbulites, Nautilus, Polystomella and + Lenticulina. + + NAUTILACEA. Lam. The sixth family of Polythalamous Cephalopoda, Lam. + containing the genera Discorbites, Siderolites, Polystomella, + Vorticialis, Nummulites, Nautilus. To these may be added Simplegas and + Endosiphonites. Fig. 472 to 476. + + NAUTILUS. Auct. (_A little boat._) _Fam._ Nautilacea, Lam. and + Bl.--_Descr._ Convolute, discoid, chambered, symmetrical; spire partly + or entirely concealed by the last whorl; aperture modified by the last + whorl, wide, sinuated on the dorsal margin; interior surface pearly; + septa dividing the chambers simple; siphon discontinuous.--_Obs._ The + shell named Nautilus by Pliny is the Argonauta of modern authors, a + thin shell, not chambered. The Nautili are known from the Ammonites by + the septa being simple, not sinuated as in the latter genus, and in + general the volutions of the spire are not visible. Three or four + species are known inhabitants of the Pacific Ocean and Australian + Ocean. The fossil species are found in the tertiary, and also in the + secondary strata, as low down as the Mountain limestone. N. pompilius, + Frontispiece. + + NAYADES. Lam. A family of the order Conchifera Dimyaria, Lam. described + as containing fresh-water bivalve shells, with or without teeth on the + hinge. They are all pearly within, and have a thick, rather smooth + epidermis without. This family contains a great variety of shells, + which have been separated into an immense number of genera, but which + G. B. Sowerby, sen. gives very good reasons for uniting under one + generic name. The most generally received distinctions are as follows: + + 1. CASTALIA. Two cardinal, one lateral, ribbed teeth. This genus is + removed from the family of Trigonacea. Fig. 140. + + 2. UNIO. Teeth various. Fig. 142, 145, 149, 148, 147, 151, 141. + + 3. HYRIA. Trigonal, alated. Fig. 143, 150. + + 4. ANODON. No teeth. Fig. 152. + + 5. IRIDINA. Hinge crenated. Fig. 150. + + NECTOPODA. Bl. The first family Nucleobranchiata, Bl. containing the + genera Carinaria and Firola; the latter is not a shell. + + NEMATOPODA. Bl. The first class of the sub-type Malentozoa, Bl. + containing all the mollusca with multivalve shells, except Chiton, and + divided into the families Lepadicea and Balanidea, corresponding with + Lamarck's sessile and pedunculated Cirripedes, and with the Linnæan + genus Lepas. + + NEMATURA. Benson. _Fam._ Turbinacea, Lam.--_Descr._ Thin, nearly oval, + somewhat compressed from back to front; spire acute, consisting of few + rounded whorls; last whorl large, but contracted near the aperture; + aperture small, oblique, rounded anteriorly; peritreme continuous, + thin; operculum spiral, horny, with few volutions.--_Obs._ The + distinguishing character of this genus is the contraction of the last + whorl near the aperture, in which respect it is nearly resembled by the + shell called Cyclostoma lucidum. Two recent and one fossil species, all + very minute, are described by Sowerby in Loudon's Magazine of Natural + History, New Series. Fig. 305. + + NERINEA. Defr. _Fam._ Canalifera, Lam.--_Descr._ Turrited, oblong, + sub-canaliculated, consisting of numerous whorls; aperture with a + strong fold on the columella, one on the outer lip, and one on the + inner lip at the edge of the body whorl.--_Obs._ This genus is only + found in a fossil state usually in the Oolitic beds, it is not + resembled by any other; the strong, prominent folds on the three upper + angles of the subquadrate aperture present a singular appearance in a + section. One species has been named N. Hieroglyphus. We give N. + Goodhallii, fig. 374. + + NERITA. Auct. _Fam._ Neritacea, Lam. Hemicyclostomata, Bl.--_Descr._ + Smooth or ribbed, semiglobose; spire short, sometimes flat, consisting + of few volutions; aperture large, semilunar; outer lip thick, entire; + inner lip thickened, dentated at the edge, spread over the body whorl, + forming a flattened disc; operculum shelly, spiral, with an appendage + by which it is locked under the sharp edge of the columella.--_Obs._ + These marine shells are known from Neritina by the thickness of the + shell and the want of the thick, horny, dark coloured epidermis; from + Natica by the flat area produced by the spreading of the thickened + columellar lip. N. Peloronta, fig. 330. N. polita, fig. 329. + + NERITACEA. Lam. A family of the first order of Trachelipoda, Lam. + containing the following genera: + + 1. NAVICELLA. Apex terminal, not spiral; inner lip septiform. Fig. + 323. + + 2. NERITA. Columellar lip septiform, edge with distinct teeth; + shell thick. Fig. 330. + + 3. NERITINA. Shell thin; columellar lip septiform, edge + denticulated; generally a thick, dark coloured epidermis. Fig. 324 + to 326. + + 4. NATICA. Having an umbilicus behind the columellar lip, with a + spiral callosity. Fig. 327, 328. + + 5. NERITOPSIS. Edge of the columellar lip with a deep notch. Fig. + 331. + + 6. PILEOLUS. Patelliform; apex central; columellar lip septiform, + leaving the aperture small. Fig. 332. + + 7. JANTHINA. Columellar lip linear; aperture angulated. Fig. 333. + + NERITINA. Lam. _Fam._ Neritacea, Lam.--_Descr._ Thin, semiglobose, + obliquely oval, smooth, flattish in front; spire short, sometimes + depressed, consisting of few rapidly increasing whorls; aperture + semicircular; outer lip thin, sharp; columellar lip broad, flat, its + inner edge straight, denticulated; operculum testaceous, semicircular, + sub-spiral, with an articulating process on the inner edge.--_Obs._ + This genus of fresh-water shells differs from Nerita in the minuteness + of the denticulation of the columella, as well as in the characters + mentioned in our observations upon the latter genus. N. spinosa, + (Clithon, Montf.) fig. 325. N. virginea, fig. 324. N. perversa, Lam. + (Velates, Montf.) fig. 326. All the species known up to the present + time, with the exception of three, are represented in the author's + Conchological Illustrations, parts 86, 87, 90, 91, 94 to 100. The + catalogue accompanying these representations enumerates 59 species. + + NERITOPSIS. Gray. _Fam._ Neritacea, Lam.--_Descr._ Sub-globose, thick, + cancellated; spire short, composed of few rapidly increasing whorls; + aperture transverse, sub-orbicular; outer lip thickened within; + columellar lip thick, rather flat, with a large rounded notch in the + centre of its inner edge.--_Obs._ This genus most nearly resembles + Nerita, from which it differs in the peculiar notch of the columella. + N. granosa, fig. 331. + + NICANIA. Leach. ASTARTE, Sowerby. The same as CRASSINA of Lamarck. + + NITIDELLA. Sw. A genus of "Columbellinæ," Sw. thus described: + "Bucciniform, small, ovate, smooth, glassy; aperture effuse; outer lip + slightly thickened, faintly inflexed, and generally striated + internally; inner lip somewhat flattened above; base of the pillar with + one or two slight internal folds, or a single angular projection. + Columbella nitida, _Lam._ (fig. 17, _c._ p. 151.)" Sw. p. 313. + + NOBIA. Leach. _Order_, Sessile Cirripedes, Lam. This genus resembles + Pyrgoma, Auct. consisting of a conical paries, supported upon a + funnel-shaped cavity in the madrepore, but differs in its operculum, + which consists of two valves, whereas that of Pyrgoma has four. N. + grandis, fig. 29. + + NODOSARIA. Lam. and ORTHOCERA have been united by Sowerby under the + name of the first. _Fam._ Orthocerata, Lam. and Bl.--_Descr._ Straight, + chambered, elongated; chambers more or less ventricose; septa + perforated by a central siphon.--_Obs._ This genus consists only of + fossils found in sub-appenine tertiary beds. It is placed by De + Blainville in one of his divisions of the genus Orthoceras, which is + characterized as "species not striated, and with chambers very much + inflated." N. æqualis, fig. 465. + + NODOSE. Having tubercles or knobs. + + NOGROBS. Montf. A fossil appearing from the figure and description to + resemble Belemnites. + + NONION. Montf. A genus of microscopic Foraminifera. + + NONIONINA. D'Orb. A genus of microscopic Foraminifera. + + NOTREMA. Rafinesque. A shell described as composed of three integral + valves, concerning which De Blainville puts the query, "ne seroit-ce + pas plutôt une Balanide mal observée?" + + NOVACULINA. Benson. (_Novacula_, a razor.) _Fam._ Solenacea, + Lam.--_Descr._ Equivalve, inequilateral, transversely elongated; + external ligament communicating with the interior of the shell by an + oblique channel; beaks prominent; hinge line nearly straight, with one + narrow curved cardinal tooth in one valve, entering between two similar + teeth in the other; siphonal scar long; extremities of the shell + gaping; epidermis thin, light brown, folding over the edges and + connecting the dorsal margins. _Hab._ Jumna, Gooti, and Ganges. Fig. + 63. + + NUCLEOBRANCHIATA. Bl. The fifth order of the second section of + Paracephalophora Monoica, Bl. the shells of which are described as + symmetrical, more or less curved, or longitudinally rolled up and very + thin. This order contains, _Fam._ 1. Nectopoda, containing Carinaria; + _Fam._ 2. Pteropoda, containing Atlanta, Spiratella and Argonauta. + + NUCLEUS. (_A kernel._) Anything forming a centre around which matter is + gathered. The nucleus of shells is the first formed part; the first + deposit of shelly matter to which the successive layers are added; the + apex of the spiral cone, of which most shells are composed. (See CONE.) + The nucleus is formed within the egg in oviparous, and within the old + shell in viviparous mollusca. It is frequently more transparent and + light than the remainder of the shell, and sometimes falls off; when + this occurs the shell is said to be decollated. + + NUCULA. Lam. (_A small nut._) _Fam._ Arcacea, Bl. and Lam.--_Descr._ + Equivalve, inequilateral, transverse, covered with an epidermis; hinge + linear, with a series of sharp, angulated teeth, arranged in a line on + each side of the umbones, and a central ligamentary pit; muscular + impressions two, simple; palleal impressions not sinuated.--_Obs._ The + row of teeth on each side of the umbones, and the ligamentary pit in + the centre of the hinge prevent the pretty little shells of this genus + from being confounded with any other. Thirty-four figures are + enumerated in the catalogue by Sowerby, sen. which accompanies the + Conchological Illustrations of the author. The new species, to the + amount of 24, have been figured in parts 14 to 16, of the above + mentioned work. Recent Nuculæ are found from the frozen to the torrid + zones, and the fossil species occur in nearly all the beds from the + Pliocene to the Carboniferous system. + + NUMMULACEA. Bl. The third family of Cellulacea, Bl. described as + containing shells or calcareous bodies, which are characterized as + discoidal, lenticular; without the slightest traces of whorls to be + seen externally. The whorls are numerous, internal, and divided into a + great number of cells, which are separated from each other by + imperforate septa. This family contains the genera Nummulites, + Siderolites, Vorticialis, Helicites, Orbiculina, Placentula. + + NUMMULTTES. Lam. (_Nummus_, money.) _Fam._ Nautilacea, Lam.--_Descr._ + Orbicular, convolute, shewing no trace of spire externally; interior + divided into cells spirally arranged.--_Obs._ The singular fossils + composing this genus receive their name from their external resemblance + to a battered coin. Fig. 472. N. lenticulina. + + NUX. Humph. CYCLAS, Lam. + + NYMPHACEA. Lam. A family belonging to the order Conchifera Dimyaria, + Lam. Ligament external, placed on a prominent fulcrum. This family + contains the following genera: + + 1. SANGUINOLARIA. Rostrated, gaping; two cardinal teeth in each + valve, including _Soletellina_ and _Lobaria_. Fig. 98, 99. + + 2. PSAMMOBIA. Quadrate; valves closed, including Psammotæa. Fig. + 100. + + 3. CORBIS. Thick, fimbriated; a cardinal tooth in the centre of a + pit. Fig. 101. + + 4. GRATELOUPIA. A series of small teeth filling a triangular area. + Fig. 102. + + 5. EGERIA. One single and one double cardinal tooth. Fig. 103. + + 6. LUCINA. Rounded; anterior muscular impression tongue-shaped. + Fig. 104. + + 7. TELLINA. An anterior fold in the ventral margin; lateral teeth. + Fig. 105, 106. + + 8. TELLINIDES. No anterior fold; no lateral teeth. Fig. 107. + + 9. DONAX. Margin denticulated; shell wedge-shaped. Fig. 108. + + 10. CAPSA. Margin not denticulated, no lateral teeth. Fig. 109. + + OBELISCUS. Humph. TROCHUS, Lam. + + OBLIQUE. (_obliquus._ lat.) In a slanting direction. The whorls of + spiral univalves generally take an oblique direction in reference to + the imaginary axis of the shell. A bivalve is said to be oblique when + it slants off from the umbones. An example of this is seen in Avicula, + fig. 163. + + OBSOLETE. (_obsoletus_, lat.) Worn out, out of use. This term is used + to express an indistinctness of character, which sometimes results from + the action of sea-water upon unprotected parts of the shell, and + sometimes from the deposits of enamel formed in age, and covering the + early striæ, ribs, teeth, &c. thereby rendering them less acute. + + OBTUSE. (_obtusus_, blunt.) The application of this term is not + peculiar to conchology. It is most frequently used to express the + character of the spire. _Ex_. The apex of Megaspira, fig. 294. + + OCEANUS. Montf. ("Corne d'ammon vivant," Fr.) NAUTILUS umbilicatus, + Auct. + + OCTHOSIA. Ranz. CLITIA, Leach. + + OCTOCERA. Bl. The first family of the order Cryptodibranchiata, Bl. + containing the genus Octopus. A species of which being found in the + Argonauta, or Paper Sailor, has given rise to the long continued + controversy as to whether it is really the constructor of the shell, or + whether it is a mere pirate, and having destroyed the true animal of + the Argonaut, has possessed itself of the habitation. This question is + now set at rest. See ARGONAUTA. + + OCTOGONAL. (_octogonum._) Having eight angles. For an example, see + Dentalium, fig. 2. + + OCTOMERIS. Sow. ([Greek: oktô], _octo_, eight; [Greek: meros], _meros_, + part.) _Fam._ Balanidea, Bl. _Order_, Sessile Cirripedes, + Lam.--_Descr._ Eight principal valves circularly arranged, forming a + compressed cone, attached by a jagged base; aperture enclosed by an + operculum, consisting of four valves in pairs.--_Obs._ The only genus + of Sessile Cirripedes agreeing with this in the number of principal + valves is Catophragmus, Sow. which is, however, sufficiently + distinguished by the several rows of smaller valves by which the + principals are surrounded at the base. O. angulosus, fig. 24. + + ODONTIS. Sow. MONODONTA, Lam. + + ODOSTOMIA. Flem. _Descr._ "Shell conical; aperture ovate; peristome + incomplete, retrally, and furnished with a tooth on the pillar." A + genus composed of several small species of land shells. Turbo plicatus, + Spiralis, Unidentatus, &c. Mont. + + OLIVA. Auct. (_An olive._) _Fam._ Convoluta, Lam. Angyostomata. + Bl.--_Descr._ Oblong, cylindrical, thick, smooth, shining; spire very + short, with sutures distinct, aperture elongated, notched at both + extremities; outer lip generally thick; columella thick, obliquely + striated, terminated by a tumid, oblique, striated varix; a raised band + passing round the lower part of the body whorl.--_Obs._ The shells + composing this well known genus present a great variety of rich + markings and brilliant colours. They are marine and tropical. Fossil + species are found sparingly in the London Clay and Calcaire-grossièr. + The Ancillariæ are distinguished from this genus by the sutures of the + whorls being covered by enamel. O. maura, fig. 457. + + OLIVELLA. Sw. A genus of "Olivinæ," Sw. thus described: "Oliviform; + spire (typically) rather produced; the tip acute; inner lip not + thickened; outer lip straight; base of the pillar curved inwards, and + marked by two strong plaits; upper plaits obsolete or wanting; aperture + effused at the base only; biplicata, Tank. Cat. 2332. purpurata. Zool. + Ill. ii. 58. f. 1. mutabilis. _Say._ eburnea. Zool. Ill. ii. 58, f. 2. + conoidalis. _Lam._ No. 57. oryza. _Lam._ No. 62." + + OLYGYRA. Say. Mentioned by Ranz as properly belonging to Helicina. H. + neritella, Auct. + + OMALAXIS. Desh. Subsequently BIFRONTIA. Desh. Fig. 354. + + ONISCIA. Sow. (G. B.) _Fam._ Purpurifera, Lam. Entomostomata, + Bl.--_Descr._ Oblong, sub-ovate, slightly turbinated, cancellated; + spire short; aperture elongated; terminating anteriorly in a very + short, recurved canal; outer lip thickened, denticulated within; inner + lip spread over a portion of the body whorl, granulated.--_Obs._ The + granulated inner lip is the principal character by which this genus is + distinguished from Cassidaria. In Oniscia the canal is not so produced. + O. oniscus, fig. 409. + + ONUSTUS. Humph. A genus proposed by Humphrey and adopted by Swainson + who describes it thus: "Shell trochiform; the surface irregular, and + often covered with extraneous bodies, cemented and incorporated with + the calcareous substance of the shell; the under part of the body whorl + flattened or concave, umbilicate. O. Solaris. Mart. 173. f. 1700, 1701. + Indicus. Ib. 172. f. 1697. 1698." It is probable, from the above + description, that Mr. Swainson intended to include Trochus agglutinans + of authors. (Genus Phorus, Montf.) Fig. 360. + + OPERCULAR. Of, or belonging to, the operculum. A term applied to the + valves which compose the operculum of multivalve shells, as + distinguished from the parietal valves, or those which are arranged + circularly and form the body of the shell. + + OPERCULINA. D'Orb. A genus of microscopic Foraminifera. + + OPERCULUM. (_A cover or lid._) The plate or plates with which many + molluscous animals enclose the aperture of their shells, when retired + within them. The operculum is sometimes horny, as in Trochus; + testaceous or shelly, as in Turbo. It is spiral when from a central or + sub-central nucleus, the successive layers take a revolving direction, + as in Trochus. It is concentric or annular when the outside edge of + each layer entirely surrounds the preceding one. It is unguiculated, + when the laminæ are placed side by side, as in Purpura. The opercula of + multivalve shells are composed of two or four pieces, which are called + the opercular valves. The shelly or membranaceous plate with which some + of the animals enclose the aperture of their shells, during the wintry + part of the year, for the purpose of protecting them while in a torpid + state, and which they get rid of by dissolving the edges, when + preparing to emerge from their temporary retirement, must not be + considered as the operculum, as it does not belong to or form part of + either the animal or its shell, but is produced for the occasion by a + secretion of the animal, being deposited in a soft state and + subsequently hardening. It is called the epiphragm, and may easily be + distinguished from the true operculum by the texture, and by the + circumstance of their being soldered to the edge of the aperture. The + operculum, on the contrary, is moveable, and is always composed of a + series of successive layers, corresponding with the growth of the + shell. + + OPIS. Defr. A genus described by De Blainville as consisting of species + of Trigonia which have the umbones sub-spiral, with a large, striated + tooth on the hinge. Opis cardissoides, Trigonia, Lam. Opis similis, + Sow. Min. Con. pl. 232. f. 2. + + ORAL. (_Os_, _oris_, mouth.) Applied to that part of a shell which + corresponds with the mouth of the animal, but very seldom used in this + sense. + + ORBICULA. Lam. (_Orbis_, an orb.) _Fam._ Brachiopoda, Lam. + Palliobranchiata, Bl.--_Descr._ Inequivalve, irregular, sub-orbicular, + compressed, attached by a fibrous substance passing through a fissure + near the centre of the lower valve; upper valve patelliform, with the + umbo central; muscular impressions four in each valve, semilunar. South + America and West Indies.--_Obs._ Discina, Lam. is an Orbicula. Crania + is known from this genus by having no fissure in the lower valve, but + being attached by its substance. Hipponyx has only two muscular + impressions in each valve. O. lævis, fig. 201. + + ORBICULAR. (_Orbiculus_, a little orb.) Of a round or circular form. + + ORBICULINA. Lam. A genus of microscopic Foraminifera. + + ORBIS. Lea. A minute fossil, described as "orbicular, with flat + quadrate whorls and aperture square," in other respects resembling + Solarium. O. Rotella, fig. 355, 356. + + ORBITINA. Risso. A genus said to be established upon the nuclei of two + land shells. + + ORBULITES. Lam. A genus separated from Ammonites on account of the last + volution covering the spire. This is generally considered as + characterizing the Nautili, and distinguishing them from the Ammonites; + but there are so many gradations that it seems impossible to maintain + the distinction in this respect. Fig. 479, O. crassus, fig. 480, O. + discus. + + OREAS. Montf. Part of CRISTELLARIA, Lam. A genus of microscopic + Foraminifera. + + ORTHIS. Dalman. ([Greek: orthos], _orthos_, straight.) _Fam._ + Brachiopoda, Lam. One of the generic divisions of Brachiopoda by + Dalman, thus described: "Hinge rectilinear, with umbones distant; the + larger valve with a transverse, basal, smooth area, with a triangular + pit." O. basalis, fig. 207. + + ORTHOCERA. Lam. See NODOSARIA. + + ORTHOCERATA. Lam. A family of Polythalamous Cephalopoda, Lam. + containing the following genera:-- + + 1. CONULARIA. Conical, externally striated; no siphon. Fig. 469. + + 2. AMPLEXUS. Cylindrical; margins of the septa reflected. Fig. 463. + + 3. ORTHOCERATITES. Straight, gradually conical; septa simple; + siphon central. Fig. 464. + + 4. NODOSARIA. Divided externally into lobes. Fig. 465. + + 5. BELEMNITES. Straight, conical; septa simple; siphon lateral; + apex solid; internal cast, or nucleus, pyramidal, separable. Fig. + 466 to 468. + + 6. CONILITES. Like Belemnites, but external shell thin at the apex. + Fig. 470. + + ORTHOCERATA. Bl. The first family of Polythalamacea, Bl. containing the + genera Belemnites, Conularia, Conilites, Orthoceras and Baculites. De + Blainville remarks that the genera included in this family are all + fossils, and known very imperfectly, in consequence of the greater part + of the specimens being only casts. + + ORTHOCERATITES. Auct. _Fam._ Orthocerata, Lam. and Bl.--_Descr._ + Straight, conical, divided into numerous chambers by simple septa + perforated by a central siphon. O. annulata, fig. 464. + + OSTEODESMA. Desh. PERIPLOMA, Schum. + + OSTRACEA. (_Ostracées_, Lam.) A family belonging to the second section + of the order Conchifera Monomyaria, the shells of which are described + as irregular, foliaceous, sometimes papyraceous, with the ligament + wholly or partly interior. The principal difference between the + Ostracea and the Pectinides consists in the absence of the auricles and + the foliated structure of the shells, for, although the Spondylus has + ex-foliations or spines upon the external surface, the shell itself is + compact and firm. This family contains the genera Gryphæa, Ostrea, + Vulsella, Placuna, Anomia, which may be thus distinguished:-- + + 1. PEDUM. Flat, turned up at the sides, an hiatus for the passage + of a byssus. A triangular disc on the hinge. Fig. 179. + + 2. OSTREA. Foliaceous, irregular, hinge on a small triangular disc. + Including Dendostrea, Ostræa, Exogyra, Gryphæa. Fig. 180 to 183. + + 3. PLACUNA. Two diverging ribs near the umbones. Fig. 184. + + 4. PLACUNANOMIA. The same, but attached by fibres passing through a + hole in one valve. Fig. 189 to 191. + + 5. ANOMIA. No costæ, attached by a bony substance passing through a + hole in one valve. Fig. 186 to 188. + + 6. VULSELLA. Tongue-shaped, a ligamentary pit on the hinge. Fig. + 185. + + 7. MULLERIA. Doubtful. Fig. 192. + + OSTRACEA. Bl. The first family of the order Lamellibranchiata, Bl. + containing the genera Anomia, Placuna, Harpax, Ostrea (including + Dendostrea, Sw.) Gryphæa. To these may be added Placunanomia, Brod. and + Mulleria. + + OSTREA. Auct. ([Greek: ostreon], _ostreon_, a bone.) _Fam._ Ostracea, + Lam. and Bl.--_Descr._ Irregular, inequivalve, generally inequilateral, + foliaceous, attached by part of the lower valve; hinge sometimes + slightly crenated; destitute of teeth; with the ligament spread upon + the lower part of a central, triangular area, which is divided into + three parts; upper valve much flatter than the lower; muscular + impressions one in each valve, large, sub-central, sub-orbicular, with + one very minute.--_Obs._ The Linnæan Genus Ostrea includes the Pectens + and many other genera so different from each other that, without any + desire to increase the number of genera, it was found necessary by + subsequent authors to separate them. The common Oyster is the type of + this genus as at present constituted, and is well known to be abundant + in various parts of the world. Those which depart furthest from this + type are the Gryphæa, Lam. with a prominent, incurved umbo in the lower + valve. The Dendostrea, Sw. with margins characterized by strongly + angulated folds, throws out arms from the lower valve, by which they + are attached to stems of sea-weed, &c. Fig. 180, O. edulis. Fig. 181, + O. folium. (Dendostrea, Sw.) Fig. 182, Gryphæa incurva. Fig. 183, + Exogyra conica. + + OTIDES. Bl. The first order of Scutibranchiata, Bl. containing the + genera Haliotis and Ancylus. + + OTION. Leach. ([Greek: ôtion], a little ear.) _Order._ Pedunculated + Cirripedes, Lam.--_Descr._ Body sub-quadrate, supported on a fleshy + pedicle with a gaping aperture and two posterior auricular tubes; + valves five, separate, two semilunar, placed at the sides of the + aperture, two terminal, very small, one dorsal, minute.--_Obs._ Otion + differs from Cineras in having two cylindrical posterior tubes, and in + the extreme minuteness of three out of five of the valves. Found on + spars floating in the sea, &c. O. Cuvierii, (Lepas aurita, Linn.) Fig. + 43, O. Cuvieri. + + OTIS. Humph. AURICULA, Lam. + + OVATE. (_Ovatus._) Egg-shaped or oval. + + OVEOLITHES. Montf. A microscopic shell resembling Bulla. + + OVIPAROUS MOLLUSCA. Those which produce their young in eggs. Used in + distinction from the VIVIPAROUS MOLLUSCA, whose young are perfectly + formed before they leave the body of the parent. + + OUTER LIP. See LABRUM. + + OVULUM. Brug. (_Ovum_, an egg, dim.) _Fam._ Convoluta, Lam. + Angyostomata, Bl.--_Descr._ Ovate or fusiform, smooth, convolute, spire + covered; aperture narrow, with a canal at each extremity; outer lip + crenulated, inflected; inner lip smooth, callous towards the spiral + extremity; dorsal area wide, sometimes indistinctly marked.--_Obs._ The + Ovula were placed by Linnæus in his genus Bulla, from which they are + very remote. They differ from Cypræa in having the inner lip smooth. We + have given representations of their different forms as follows: O. + Ovum, fig. 442. O. verrucosum, (Calpurnus Montf.) fig. 441. O. Volva, + the weaver's shuttle (Radius, Montf.) fig. 442. O. gibbosum, (Ultimus, + Montf.) fig. 443. + + OXYSTOMATA. Bl. The fifth family of Asiphonibranchiata, Bl. This family + appears to have been formed for the express purpose of providing a + place in the system for the genus Janthina, which seems to bear so + little analogy with other genera of Mollusca, that conchological + writers have been puzzled to know where to place it. + + PACHYLABRA. Sw. PACHYSTOMA, Guild. A sub-genus of Ampullaria, the outer + lip of which is thickened within. _Ex._ Ampullaria globosa. + + PACHYMYA. Sow. ([Greek: pachus], _pachus_, thick, and _Mya_.) _Fam._ + Cardiacea? Lam.--_Descr._ Obliquely elongated, equivalve, thick, + sub-bilobed, with beaks near the anterior extremity; ligament partly + immersed attached to prominent fulcra.--_Obs._ This singular fossil is + shaped like Modiola, but the shell being extremely thick, and the + ligament attached to a prominent fulcrum, it is difficult to know where + to place it. Fig. 130, Pachymya Gigas. + + PACHYSTOMA. Guild. ([Greek: pachus], _pachus_, thick; [Greek: stoma], + _stoma_, mouth.) A genus composed of such species of Ampullaria, Auct. + as have the edge of the aperture thickened and grooved within so as to + form a sort of ledge upon which the operculum rests. Ampullaria globosa + and corrugata are examples of this variation. The name Pachylabra is + given to such species by Swainson, who objects to the above name on + account of its having been previously used to a genus of fishes. Fig. + 539. + + PACHYTOMA. Sw. A sub-genus of Helicina, thus described, "Aperture + entire; the inner lip very thick; the spiral whorls hardly convex; P. + occidentalis. Zool. J. iii. 15. f. 6-10. viridis, Zool. Journ. i. pl. + 6. f. 7." Sw. p. 337. + + PACLITES. Montf. A genus composed of species of Belemnites, Auct. + described towards the extremity, with a pore, at the apex, and a + straight lengthened aperture. _Ex._ B. ungulatus, Bl. + + PADOLLUS. Montf. A genus composed of species of HALIOTIS, with a + strongly marked spiral groove. _Ex._ H. tricostalis, Lam. Fig. 339. + + PAGODELLA. Sw. A sub-genus of Trochus, thus described: "Trochiform; + generally thin, and always not pearlaceous; aperture and pillar + perfectly united and entire; operculum horny. P. major. Mart. 163. f. + 1541, 1542. tectum-persicum. Ib. f. 1543, 1544." Sw. p. 351. + + PALLEAL IMPRESSION. (_Pallium_, a mantle.) The mark or groove formed in + a bivalve shell by the muscular attachment of the mantle, which, being + always found near the margin of the shell, is sometimes termed the + marginal impression. In bivalves with two muscular impressions it + passes from one to the other. If in passing, it takes a bend inwards + posteriorly, it is said to be sinuated, and that part is called by Mr. + Gray, the Siphonal scar. + + PALLIOBRANCHIATA. Bl. The first order of the class Acephalophora. Bl. + The animals of this order are described as more or less compressed, + included between the two valves of a bivalve shell, one inferior, the + other superior, joining at the back and opening in front. The + Palliobranchiata in the system of De Blainville correspond with the + Brachiopoda in the system of Lamarck, and the shells may be known by + their being symmetrical. This order contains in the first section of + symmetrical bivalves, Lingula, Terebratula, Thecidium, Strophomena, + Plagiostoma, Dianchora and Podopsis: in the second section, Orbicula + and Crania. + + PALMATED. Flattened like a palm, as the fronds or fringes of some + Murices. + + PALMINA. Gray. Differing from OTION in having but one auricle. + + PALUDINA. Lam. _Fam._ Peristomata, Lam. Cricostomata, Bl--_Descr._ + Varying in form from oval to globose, in some instances oblong, covered + with a greenish horny epidermis; spire acute, composed of rounded + whorls; aperture ovate; peritreme entire, slightly modified by the last + whorl; operculum horny, concentric. Europe, North America, East Indies, + China, &c.--_Obs._ The construction of the operculum distinguishes this + genus of freshwater shells from Valvata and Cyclostoma. The Paludinæ + are viviparous. Fig. 321. P. Achatina. + + PALUDOMUS. Sw. A genus of the family of "Melanianæ," Sw. described as + differing from Melania in having the spire shorter than the aperture. + Sw. p. 340. + + PANDORA. Brug. _Fam._ Corbulacea, Lam. Pyloridea, Bl.--_Descr._ Thin, + inequivalve, pearly within, rounded anteriorly, rostrated posteriorly; + right valve flat with a cardinal tooth, or short rib, and a slit + containing the cartilage with a narrow plate on the dorsal edge turned + towards the left valve; left valve concave, with a receptacle for the + cardinal tooth of the right valve and the internal cartilage; no + external ligament. Europe, America, Ceylon, &c.--_Obs._ This well known + genus is in no danger of being confounded with any other shell. Fig. + 90. P. rostrata. + + PANOPÆA. Menard. _Fam._ Solenacea, Lam. Pyloridea, Bl.--_Descr._ + Equivalve, inequilateral, oval, gaping at both extremities; hinge with + an acute cardinal tooth in each valve, and a large callosity near the + umbones supporting the ligament; muscular impressions two, distant, + oval; palleal impression with a large sinus. Britain, North America, + Mediterranean, Australia, &c.--_Obs._ This genus resembles Mya in + general appearance, but differs in having an external ligament and a + sharp tooth, instead of the broad spoon-shaped process in the hinge of + the latter genus. Fig. 65. P. Australis. + + PAPER SAILOR. A common name given to the Argonauta. + + PAPILLARY. (_Papilla_, a teat.) Shaped like a teat. This term is + applied by conchologists when the apex of the spire of an univalve + shell is rounded like a teat and not spiral up to the extreme point; as + the apex of Cymba, fig. 434. + + PAPYRACEOUS. (_Papyrus_, a kind of paper made of the flags of the river + Nile in Egypt.) Of a thin, light texture, resembling that of paper. An + example of this is to be seen in the Argonauta, commonly called the + "Paper Sailor," fig. 485, and in the Pholas papyracea, fig. 56. + + PAPYRIDEA. Sw. A sub-genus of Cardium, thus described; "Shell + heart-shaped, or transversely oval; inequilateral; the anterior side + almost always gaping; representing the Pholidæ. P. Soleniforme, Wood, + Conch. pl. 56. f. 3.--apertum, Ib. 56. f. 2.--transversum, Sow. Conch. + f. 4.--ringens, Wood, pl. 53. f. 1, 2." + + PARACEPHALOPHORA. Bl. The second class of the type Malacozoa, Bl. + divided into the sub-classes: P. dioica, P. monoica, P. hermaphrodita. + + PARIES. (_A wall._) The principal part of a multivalve shell, forming a + circular wall round the body of the animal, and composed of one or more + valves which are called the parietal valves. + + PARIETAL VALVES. The principal valves of multivalve shells surrounding + the body like a wall; as distinguished from the opercular valves, or + those which compose the operculum. + + PARMACELLA. Cuv. (_A little cell._) _Fam._ Limacinea, Lam. and + Bl.--_Descr._ Haliotoid, internal, thin; spire flat, consisting of one + or two rapidly increasing whorls; aperture as large as the whole shell, + with the dorsal margins inflected.--_Obs._ This description applies to + Parmacella of Cuvier. The shell figured in Sowerby's Genera under that + name is Cryptella of Webb. Fig. 257, P. Olivieri. Fig. 258, P. + Palliolum. + + PARMOPHORUS. Bl. A genus composed of EMARGINULA elongata, Auct. and + other species of a similarly elongated form. Australian. Fig. 242. P. + elongatus. + + PARTULA. Fer. _Fam._ Colimacea, Lam. Auriculacea, Fer.--_Descr._ + Conical, smooth; spire equal to the aperture in length, consisting of + few whorls; aperture auriform; outer lip reflected, broad; inner lip + reflected, with a slight prominence on the columella. P. australis, + fig. 302. + + PASITHÆA. Lea. A genus formed of some pyramidal shells, described as + resembling Melania, but separated from that genus on account of being + marine fossils. Fig. 317, P. striata. + + PATELLA. Auct. (_A dish_ or _platter_.) _Fam._ Phyllidiana, Lam. + Retifera, Bl.--_Descr._ Symmetrical, compresso-conical, nearly regular, + oblong or oval; apex sub-central, inclining towards the anterior + margin; aperture oval, forming the base of the shell; internal surface + smooth; with a muscular impression shaped like a horse-shoe, with the + ends bending forwards, encircling and dividing the space all round, + except where the interruption occurs to receive the head of the animal; + external surface ribbed, grooved, striated or banded radiately. On + rocks and sea-weeds in all climates.--_Obs._ Patelloida differs from + Patella in the construction of the animal; Siphonaria, in the lateral + siphon; and Ancylus, in the oblique twist of the axis, as well as in + the nature of the animal. The Patellæ are marine. Fig. 229, P. Oculus. + + PATELLIFORM. (_Patella_, a dish; _forma_, shape.) Shaped like a dish, + or like shells of the genus Patella. + + PATELLOIDA. Quoy and Gaimard. LOTTIA, Gray.--_Fam._ Phyllidiana, + Lam.--_Descr._ Patelliform, rather flat; apex obtuse, leaning towards + the posterior margin; muscular impression not symmetrical, but widest + on the right side near the head of the animal; central disc of a + variable brown colour. On rocks and sea-weeds in all climates.--_Obs._ + The shells of this genus so closely resemble Patella that it is almost + impossible to make the distinction from the shells alone. They are, + however, generally flatter, and have the apex placed somewhat nearer + the posterior margin. The animals are very distinct. Fig. 231, P. + Antillarum. + + PATELLOIDEA, Bl. or patelliform shells. The third family of the order + Monopleurobranchiata, Bl.; the animals of which are described as + depressed, flattened, covered by a wide external shell, which is + patelliform and non-symmetrical. This family contains the genera + Umbrella and Siphonaria. + + PATROCLES. Montf. A genus of microscopic Foraminifera. + + PATULARIA. Sw. A sub-genus of "Anodontinæ," Sw. thus described: "Shell + nearly equilateral, round or cordate; no teeth. P. ovata, Sw." _Ex._ + _Conch._ pl. 36. rotundatus, Ib. pl. 137. + + PAVONIA. D'Orb. A genus of microscopic Foraminifera. + + PAXYODON. Schum. HYRIA, Lam. + + PECTEN. Brug. (_A comb._) _Fam._ Pectenides, Lam. Subostracea, + Bl.--_Descr._ Inequivalve, ribbed longitudinally, nearly equilateral, + with a triangular auricle on each side of the umbones; hinge linear, + destitute of teeth, having a central pit containing the cartilage; + muscular impressions one in each valve, large, sub-central.--_Obs._ + This genus of beautiful shells, to which the well known Scallop + belongs, contains numerous species, some of which are found in the + British Seas. The Hinnites Pusio (P. Pusio of some authors) has been + separated on account of the irregularity of the external surface of one + valve. Fig. 171 to 173. + + PECTENIDES. Lam. A family belonging to the second section of the order + Conchifera Dimyaria, Lam. including the following genera. + + 1. PECTEN. Unattached, including _Decatopecten_ and _Hinnites_. + Fig. 171, 172, 173. + + 2. LIMA. Unattached, gaping, Fig. 174. + + 3. PLAGIOSTOMA. Unattached, with an area between the umbones. Fig. + 176. + + 4. DIANCHORA. Attached by the point of the umbo. Fig. 175. + + 5. SPONDYLUS. Attached, irregular, a triangular area in one valve, + divided by a slit. Fig. 177. + + 6. PLICATULA. Plicated, a very small area in one valve. Fig. 178. + + PECTINATED. (_Pecten_, a comb.) Marked in a regular series of ridges. + + PECTUNCULUS. (_Pecten_, dim.) _Fam._ Arcacea, Lam. and Bl.--_Descr._ + Equivalve, sub-equilateral, orbicular, thick, covered with a velvety + epidermis, striated longitudinally; ventral margin denticulated within; + hinge semi-circular, with a series of small teeth on each side of the + umbones, which are separated by a small triangular disc in each valve + bearing the ligament; muscular impressions two in each valve, strongly + marked, united by an entire palleal impression.--_Obs._ Linnæan + conchologists have mixed this genus with Arca, from which it is, + however, totally distinct, not only in the roundness of the general + form, but also, and principally, in the curve of the hinge line; in + fact the characters of this genus are so strongly marked that there is + no danger of confounding it with any other. It does not contain many + species; two or three are British. The fossil species occur in London + Clay and Calcaire-grossiér. Fig. 134, P. pilosus. + + PEDICLE or PEDUNCLE. (_Pedunculus_, a little foot.) The stem or organ + of attachment of the class of shells called in the system of Lamarck + "Pedunculated Cirripedes," consisting of a fleshy tendinous tube, by + the lower end of which they are attached to sub-marine substances. + + PEDICULARIA. Sw. A genus of "Scutibranchia," thus described: "Shell + irregular, sub-patelliform; a thick, large, obsolete apex on one of the + longest sides, and an internal callous rim within, on one side only; + circumference undulated, irregular. P. Sicula, Sw." Sw. p. 357. Sicily. + A singular shell of the nature of Calyptræa, which is found attached to + corals, conforming its shape to the irregularity of their surface, and + fitting closely. _Ex._ Fig. 513. + + PEDIPES. Adanson. _Fam._ Auriculacea, Bl. Colimacea, Lam.--_Descr._ + Sub-globose, longitudinal, thick, striated; spire equal to the aperture + in length; aperture sub-ovate; peritreme sharp, thickened within, + modified by the last whorl; columella with three strong plaits on the + inner edge; outer lip with one fold.--_Obs._ This genus contains but + one or two small recent species, which in some respects resemble + Auricula, from which it is known by the thickness of its shell, and its + globular form. Fig. 299, P. Adansoni. Coast of Africa. + + PEDUM. Lam. (_A shepherd's crook._) _Fam._ Pectinides, Lam. + Sub-ostracea, Bl.--_Descr._ Irregular, inequivalve, sub-equilateral, + attached by a byssus passing through a sinus in the lower valve; hinge + toothless, with a triangular area in each valve, separating the + umbones; ligament contained in a groove running across the area; + muscular impressions one in each valve, large, sub-orbicular; both + valves flat, narrow at the dorsal, broad at the ventral extremities; + lower valve with raised edges overwrapping the upper.--_Obs._ This + singular genus, of which only one species is known, differs from + Ostrea, not only in shape and structure, but also in the mode of + attachment, which is by means of a byssus passing through the lower + valve, in Pedum, but by a portion of the outer surface of the shell in + Ostrea. P. Spondyloideum (fig. 179) is the only species at present + known. Moluccas. + + PEDUNCLE. See PEDICLE. + + PEDUNCULATED. (_Pedunculus_, a little foot.) Attached to external + objects by a hollow fleshy tube, called the Peduncle. + + PEDUNCULATED CIRRIPEDES. Lam. An order consisting of molluscs which + have multivalve shells, supported on a peduncle. The genera which it + contains are thus distinguished: + + 1. PENTELASMIS. Five valves. Fig. 34. + + 2. CINERAS. Five very minute valves distant from each other. Fig. + 42. + + 3. OTION. The same, but the animal has two auricles. Fig. 43. The + genus Palmina, Gray, has but one. + + 4. OCTOLASMIS. Shaped like Pentelasmis, but with 7 or 8 valves. + Fig. 41. + + 5. LITHOTRYA. Five valves, peduncle scaly with a plate at the base. + Fig. 39. + + 6. SCALPELLUM. Shape square, valves 13, peduncle scaly. Fig. 35. + + 7. SMILIUM. Same, but the peduncle hairy. Fig. 36. + + 8. IBLA. Four valves, one pair long, one pair short, peduncle + hairy. Fig. 40. + + 9. BRISMEUS. Seven valves, even at the base. Fig. 38. + + 10. POLLICIPES. Principal valves in pairs, with many smaller valves + at the base. This genus has been divided into _Pollicipes_, and + _Capitellum_, the latter of which is founded upon Pollicipes + Mitellus, Auct. Fig. 37 and 37*. + + PELAGUS. Montf. A genus composed of species of AMMONITES, which have + the spire covered by the last whorl, as in Nautilus and have an + umbilicus. ORBULITES. Bl. + + PELLUCID. Transparent. + + PELORUS. Montf. POLYSTOMELLA, Bl. A genus of microscopic Foraminifera. + + PELORONTA. Oken. NERITA _Peloronta_, Auct. Fig. 330. + + PENEROPLIS. Montf. A genus of microscopic Foraminifera. + + PENICILLUS. Brug. ASPERGILLUM, Auct. + + PENTALEPAS. Bl. PENTELASMIS, Auct. + + PENTAMERUS. Sow. ([Greek: Pente], _pente_, five; [Greek: meros], + _meros_, part.) _Fam._ Brachiopoda, Lam.--_Descr._ Equilateral, + inequivalve; one valve divided by a central septum into two parts; the + other by two septa, into three parts; umbones incurved, + imperforate.--_Obs._ Dalman remarks upon his genus Gypidia, that it is + most probably identical with PENTAMERUS, Sow. but rejects the name for + two reasons; 1st. That it has already been applied to a class of + insects; 2nd. He disputes the fact of the shell being quinquelocular, + i.e. not counting the triangular foramen in the hinge of the larger + valve as one of the divisions. Fig. 212, 213. + + PENTELASMIS. Leach. ([Greek: pente], _pente_, five; [Greek: elasma], + _elasma_, plate.) _Order._ Pedunculated Cirripedes, Lam.--_Descr._ + Compressed, conical, composed of five valves; lower lateral pair + sub-trigonal; upper lateral pair elongated, sub-quadrate; dorsal valve + arcuate, peduncle elongated, smooth. Found on floating wood in the + sea.--_Obs._ This genus is known from all others of the order by the + number of valves. Pentelasmis is the genus Anatifera of Lamarck. Lepas + anatifer, Linn. Fossil species of this marine genus are found in the + Calcaire-grossièr of Paris, and in other similar beds. Fig. 34, P. + lævis. + + PENULTIMATE WHORL. The last whorl but one. + + PERA. Leach. A genus composed of CYCLAS amnica, and other similar + species. + + PERDIX. Montf. DOLIUM _Perdix_, Auct. + + PERFORATED. (_Perforatus._) Bored through, as the apex of Fissurella, + fig. 245, and Dentalium, fig. 2. + + PERFORATION. (_Perforo_, to bore, or pierce.) A round opening, having + the appearance of being bored, as in Haliotis, fig. 338. Sometimes the + term is applied to an umbilicus which penetrates a shell through the + axis to the apex, as Eulima splendidula, fig. 348. + + PERIBOLUS. Brug. A genus founded upon young specimens of CYPRÆA, with + their outer lips not formed. + + PERIOSTRACUM. A name used by Mr. Gray to signify the substance which + covers the outer surface of many shells, called the _Epidermis_ by most + conchological writers. "Drap Marin" is the name given to this substance + by French Naturalists. + + PERIPLOMA. Schum. _Fam._ Myariæ. A genus thus described: "Shell very + thin with the left valve more ventricose than the right; hinge + toothless, ligament double, the external portion thin, the internal + part thick, placed upon prominent, sometimes spoon-shaped hinge laminæ, + and supported by a transverse bone; muscular impressions two, distant, + palleal impression sinuated posteriorly." _Ex._ P. inæquivalvis. fig. + 72. _Genus_, Osteodesma, Deshayes. + + PERISTOMATA. Lam. A family belonging to the first section of the order + Trachelipoda, containing the following genera:-- + + 1. AMPULLARIA. Globose or discoidal; operculum concentric; + including _Pachystoma_, _Lanistes_, _Ceratodes_. Fig. 318 to 320. + + 2. PALUDINA. Oval; operculum concentric. Fig. 321. + + 3. VALVATA. Globose; operculum spiral. Fig. 322. + + PERISTOME. The edge of the aperture, including the inner and outer + lips. + + PERITREME. A term used to express the whole circumference of the + aperture of a spiral shell. It is said to be notched or entire, simple, + reflected, round or oval, &c. + + PERLAMATER. Schum. (_Mother of Pearl._) MELEAGRINA Margaritifera, Lam. + The pearl oyster. + + PERNA. Auct. ("Pernæ concharum generis," Plin.) _Fam._ Malleacea, + Lam.--_Descr._ Sub-equivalve, irregular, compressed, foliaceous; hinge + straight, linear, composed of a series of transverse, parallel grooves, + containing the cartilage and intermediate spaces bearing the ligament; + anterior margin with a sinus for the passage of a byssus; posterior + ventral margin oblique, attenuated. _Obs._ This genus is known from + Crenatula by the straightness, number and regularity of the grooves in + the hinge and the sinus, for the passage of the byssus. Fig. 166, P. + Ephippium. Mostly tropical. + + PERSICULA. Schum. A genus formed of MARGINELLA _Persicula_, Auct. and + other species having the spire concealed. Fig. 438. + + PERSONA. Montf. (_Mask_). A genus composed of TRITON _Anus_, Auct. and + similar species. Fig. 401. + + PETRICOLA. Lam. (_Petrus_, a stone; _cola_, an inhabitant.) _Fam._ + Lithophagidæ, Lam.--_Descr._ Equivalve, inequilateral, transversely + ovate or oblong, rather irregular, anterior side rounded; posterior + side more or less attenuated, slightly gaping; hinge with two cardinal + teeth in each valve; muscular impressions two in each valve; palleal + impression entire; ligament external.--_Obs._ The Petricolæ are found + in holes made by the animals in rocks, madrepores, &c. They may be + known from Saxicava by the regularity of their form and the teeth on + the hinge. Fig. 91, 92. + + PETRIFIED FINGERS, CANDLES, SPECTRE CANDLES, &c. are vulgar terms by + which fossils of the genus Belemnites were formerly known. + + PHAKELLOPLEURA. Guild. A genus composed of those species of CHITON, + Auct. which have bunches of hairs or hyaline bristles on each side of + each valve on the margin. The Chiton fascicularis, found on our own + coasts, is a well known example. Fig. 506. + + PHARAMUS. Montf. LENTICULINA, Bl. A genus of microscopic Foraminifera. + + PHARETRIUM. König. ([Greek: pharetreôn], _pharetrion_, a + quiver.)--_Descr._ A testaceous body composed of two conical sheaths, + one within the other, perforated at the apex, and joined together near + the oral margin. P. fragile, fig. 3. In describing this genus, which + appears to be the same as ENTALIS of Defrance, Mr. König expresses the + supposition that it may probably belong to the class Pteropoda. + + PHASIANELLA. Auct. (_Phasianus_, a pheasant.) _Fam._ Turbinacea, Lam. + Ellipsostomata, Bl.--_Descr._ Smooth, oval, variegated; aperture + entire, oval; outer-lip thin; inner-lip thin, spread over a portion of + the body whorl; columella smooth, rather thickened towards the base; + operculum horny, spiral within; testaceous, incrassated without. + Britain, Mediterranean, &c.; the fine large species are Australian. + Some fossil species are found in the tertiary beds.--_Obs._ The shells + composing this genus are richly marked with lines and waves of various + and delicate colours, and if the genus be restricted to those species + which are smooth, and which have a thick shelly operculum, we may + regard it as well defined; but there are some spirally-grooved species + of TURBO, Linn. which, from their oval shape, have been considered as + belonging to this genus. Such species should not, in our opinion, be + retained in this genus; they belong to Littorina. P. variegata, fig. + 367. + + PHITIA. Gray. CARYCHIUM, Müller. + + PHOLADARIA. Lam. A family of the order Conchifera Dimyaria, Lam. The + animals contained in this family live in cavities bored by themselves + in rocks, wood, &c. They are cylindrical in form. Lamarck here places + PHOLAS and GASTROCHÆNA, the last of which belongs more properly to the + family of Tubicolaria, where we have enumerated it. Pholas has been + divided into _Pholas_, fig. 55, _Martesia_, which has the valves nearly + closed; and Pholadidæa, fig. 56, which has the cup-shaped extension. + The genus Pholadomya, fig. 67, has been added, although of doubtful + character. The genus Galeomma, fig. 58, 59, has also been recently + added. + + PHOLADIDÆA. Leach. PHOLAS papyracea, Auct. Remarkable for the + cup-shaped process at the posterior extremity. Fig. 56. + + PHOLADOMYA. Sow. (_Pholas_ and _Mya_.) _Fam._ Pholadaria, + Lam.--_Descr._ Thin, rather hyaline, equivalve, inequilateral, + ventricose, posteriorly gaping, elongated, anteriorly short, rounding; + ventral margin rather gaping; hinge with an elongated pit, and lateral + plate in each valve; ligament external, short, muscular impressions two + in each valve, rather indistinct; palleal impression with a large + sinus.--_Obs._ The only recent species of this genus is from the island + of Tortola. Several fossil species occur in rocks of the Oolitic + series. Fig. 57, P. candida. + + PHOLAS. Auct. ([Greek: PHôleô], _pholeo_, to lie hid in a cavity.) + _Fam._ Pholadaria, Lam. ADESMACEA, Bl.--_Descr._ Transverse, oblong, + equivalve, inequilateral, imbricated, gaping on both sides, the + anterior hiatus being generally the largest, although sometimes nearly + closed, with the dorsal margin surmounted with one or more laminar + accessary valves; hinge callous, reflected, with a long curved tooth + protruding from beneath the umbones in each valve.--_Obs._ This genus + of marine shells, dwelling in holes formed in rocks, wood, &c. is + easily distinguished from any other nearly allied genus by the curved, + prominent, rib-like teeth. Fig. 55, P. Dactylus; 56. P. papyracea. + + PHOLEOBIUS. Leach. Part of the genus SAXICAVA, Auct. + + PHONEMUS. Montf. A genus of microscopic Foraminifera. + + PHORUS. Montf. TROCHUS agglutinans, Auct. Remarkable for the adhesion + of little pebbles, dead shells, &c. to the outer edge of the whorls, + which are taken up in the course of the growth of the shell. From this + circumstance they are called "Collectors, Carriers, &c." Fig. 360. + Recent species are brought from the East and West Indies; fossil + species are found in the Tertiary beds. + + PHOS. Montf. _Fam._ Purpurifera? Lam.--_Descr._ Turrited, thick, + cancellated, varicose; spire pointed, generally longer than the + aperture; aperture rounded or oval; outer lip having internal ridges, + with a sinus near the anterior termination; columella with an oblique + fold; canal short, forming externally a raised varix.--_Obs._ The + raised external surface of the canal, brings this genus near to + Buccinum, while, in general appearance, most of the species more nearly + resemble Murex. They have, however, no true varices on the whorls, but + merely raised bars. Fig. 416, P. senticosus. + + PHYLLIDIANA. Lam. A family belonging to the first section of the order + Gasteropoda, Lam. The genera belonging to this family may be + distinguished as follows: + + 1. CHITON. Composed of eight valves; valves contingent. Fig. 227. + + 2. CHITONELLUS. The same, with the valves distant. Fig. 228. + + 3. PATELLA. Conical, symmetrical. Fig. 229, 230. + + 4. PATELLOIDA. Differing from Patella in the animal. Fig. 231. + + 5. SIPHONARIA. With a siphon on one side. Fig. 231*. + + 6. SCUTELLA. Siphon close to the side of the head. Fig. 510, 511. + + PHYLLONOTUS. Sw. A sub-genus of Murex, thus described: "Canal moderate; + varices foliated, laciniated, compressed, or resembling leaves; + inflatus. Mart. 102. fig. 980, eurystoma. Zool. Ill. ii. 100. + imperialis. Ib. pl. 109." Sw. p. 296. + + PHYSA. Drap. A genus formed for reversed species of Limnæa, Auct. Fig. + 310, P. castanea. + + PHYSETER. Humph. SOLARIUM, Lam. + + PILEOLUS. Cookson. (_A little cap._) _Fam._ Neritacea, Lam.--_Descr._ + Patelliform, with the apex sub-central, straight. In the lower disc, or + under surface, the centre of which is rather raised or cushion-shaped, + is placed the lateral, narrow, semilunar aperture, with the outer lip + marginated and the inner lip crenulated.--_Obs._ This interesting genus + is known only in a fossil state. Two species are found in the upper + layer of Oolite, above the Bradford clay. The spire, although internal, + connects this genus in some degree with Neritina. Still there is no + danger of confounding them. Fig. 332, P. plicatus. + + PILEOPSIS. Lam. CAPULUS, Montf. + + PILLAR. The usual English name for the column which forms the axis of + spiral shells, around which the whorls revolve. See COLUMELLA. + + PINNA. Auct. (_The fin of a fish._) _Fam._ Mytilacea, Lam.--_Descr._ + Equivalve, inequilateral, oblique, wedge-shaped, thin, horny; umbones + terminal; hinge rectilinear, without teeth; anterior margin sinuated, + to admit the passage of a byssus; posterior margin truncated, gaping; + muscular impressions two in each valve; posterior large, sub-central; + anterior small, terminal, sometimes double.--_Obs._ The beautiful large + shells of which this genus is composed, are possessed of a large, + flowing, silky byssus, of which gloves and hose have been manufactured. + They have received their name from their resemblance to the pectoral + fins of some fishes. Some species attain very large dimensions, and + measure two feet in length. A very improbable story is told with regard + to animals of this genus, namely that a certain small species of crab + is in the habit of taking refuge from its enemies in the shell of the + Pinna, into which it is received with great hospitality and kindness by + the "_blind slug_," which inhabits it. In return for which kindness, he + occasionally goes abroad to procure food for both. On his return he + knocks at the shell, which is opened to receive him, and they share the + supplies together in convivial security! Some species are smooth, + although the greater number are imbricated or crisped outside. P. + saccata, fig. 162. + + PINNATED. (From _Pinna_, a fin.) When a part of a shell is spread out + and smooth, as in Rostellaria columbaria, fig. 403, it is said to be + _alated_, or winged, but when the part which is spread is radiated or + ribbed, like the fin of a fish, it is _pinnated_, as in Murex pinnatus, + and Murex tripterus. (Conch. Illustr.) + + PIRENA. Lam. A genus of fresh-water shells, rejected by De Ferussac and + other authors, who place Lamarck's two first species with Melanopsis, + and his two last with Melania. Fig. 316, P. terebralis. + + PISIDIUM. Leach. A genus of river shells separated from Cyclas + principally on account of a difference in the animal. The species of + Pisidium, however, are less equilateral than the Cyclades, and the + posterior or ligamentary side of the latter is the longer, while that + of the former is the shorter. Fig. 112. + + PISIFORM. (_Pisum_, a pea; _forma_, shape.) Shaped like a pea or small + globular body. + + PISUM. Megerle. (_A pea._) PISIDIUM, Leach. + + PITHOHELIX. Sw. A sub-genus of "Geotrochus," Sw. Sw. p. 332. + + PITONELLUS. Montf. ROTELLA, Auct. + + PLACENTA. Schum. PLACUNA, Auct. + + PLACENTULA. Schum. A genus of microscopic Foraminifera. + + PLACUNA. Brug. ([Greek: plakous], _placos_, a cake.) _Fam._ Ostracea, + Lam. and Bl.--_Descr._ Compressed, thin, equivalve, nearly equilateral, + planorbicular, fibrous, foliaceous; hinge flat, with two diverging ribs + in one valve, and two corresponding grooves in the other, containing + the cartilage; muscular impressions one, large, circular, central, and + one or two smaller in each valve.--_Obs._ The two best known species of + this well defined genus are the P. Placenta, commonly called the + Chinese Window Shell, and the P. Sella, called the Saddle Oyster, from + the anterior margin being turned up so as to resemble a saddle. The + genus may be known from all others by the diverging costa on the hinge. + Placunanomia is the only genus resembling it in this respect, but this + is easily distinguished by a perforation through the shell. Fig. 184, + P. Placuna. These shells are used in China to glaze windows. + + PLACUNANOMIA. (Sw. _Placuna_ and _Anomia_.) _Fam._ Ostracea, Lam. and + Bl.--_Descr._ Thin, foliaceous, compressed, sub-equivalve, + sub-equilateral, irregular, flat near the umbones, plicated towards the + margins, attached by a bony substance passing through a fissure in the + lower valve; hinge flat, with two diverging ribs in one valve, + corresponding with two diverging grooves, containing the cartilage, in + the other; muscular impressions one in each valve, central, + sub-orbicular.--_Obs._ The specimens from which Mr. Broderip described + this singular genus, were brought by Mr. Cuming from the gulf of Dulce + in Costa Rico. Another species is from one of the Philippine Islands. + They partake of the characters of several genera, having the hinge of + Placuna, and being attached by a process passing through the lower + valve, like Anomia. P. Cumingii, fig. 189. + + PLAGIOSTOMA. Sow. Min. Con. ([Greek: plagios], _plagios_, oblique; + [Greek: stoma], _stoma_, mouth.) _Fam._ Pectenides, Lam. + Palliobranchiata, Bl.--_Descr._ Sub-equivalve, inequilateral, oblique, + auriculated on each side of the umbones, radiately striated; hinge + straight in one valve, with a triangular notch in the other.--_Obs._ + This genus, one species of which is spinous, and another smooth, is + only known in a fossil state. It is found in the Lias and chalk. Fig. + 176, P. spinosum. + + PLAIT or FOLD. A term applied to the prominences on the columellar lip + of some univalve shells, particularly in the sub-family of Volutidæ. + _Ex._ Voluta, fig. 433; Cymba, 434; and Melo, fig. 435. + + PLANARIA. Brown. A minute fossil resembling Planorbis in appearance, + but differing in being a marine shell, and having a reflected outer + lip. P. nitens, fig. 312, from Lea's Contributions to Geology. + + PLANAXIS. Lam. (_Plana_, flat; and _axis_.) _Fam._ Turbinacea, Lam. + Entomostomata, Bl.--_Descr._ Sub-ovate, pyramidal, solid; spire + measuring ½ or 1/3 of the axis, consisting of few whorls; columella + contiguous to the axis, flat, truncated, and separated from the outer + lip by a short canal; outer lip thickened and denticulated within; + operculum horny, thin, with a terminal nucleus.--_Obs._ This is a genus + of small marine shells found in the West Indies, &c. Fig. 365, P. + sulcata. + + PLANE. (_Planus._) Flat, planed, as the columellar lip of Purpura, fig. + 414. + + PLANORBICULAR, (_Planus_, flat; _orbis_, an orb.) Flat and circular, as + Ammonites, fig. 478. + + PLANORBIS. Müll. (_Planus_, flat; _orbis_, an orb.) _Fam._ Lymnacea, + Lam. and Bl.--_Descr._ Thin, horny, convolute, planorbicular, nearly + symmetrical; spire compressed, concave, consisting of numerous + gradually increasing whorls, which are visible on both sides; aperture + transversely oval, or nearly round; peritreme entire; outer lip thin; + inner lip distinct, spread over a part of the body whorl.--_Obs._ This + is a genus of shells abounding in all climates in ditches and stagnant + pools, not liable to be confounded with any other, excepting the + discoidal species of Ampullaria, which may be distinguished by the + aperture being broadest in the opposite direction. It is further to be + remarked that the discoidal Ampullariæ are dextral shells, and the + Planorbes are sinistral or reversed; and although the latter are + sometimes so flat and orbicular that it is difficult to know which is + the spiral side, it may nevertheless always be ascertained by a careful + examination. Fossil species are found in the freshwater strata of the + Isle of Wight, and the neighbourhood of Paris. Fig. 311, P. corneus. + + PLANORBULINA. D'Orb. A genus of microscopic Foraminifera. + + PLANULACEA. Bl. The second family of Cellulacea, Bl. The microscopic + Foraminifera contained in this family are described as very much + depressed, not spiral, chambered, cellular, and having the septa + indicated by grooves on the external surface of the shell, which + increase in length from the apex to the base: some of the small + cellular cavities are to be seen on the margins. This family contains + the genera Renulina and Peneroplis. + + PLANULARIA. Defr. PENEROPLIS, Montf. A genus of microscopic + Foraminifera. + + PLANULINA. D'Orb. A genus of microscopic Foraminifera. + + PLANULITES. Lam. DISCORBITES of the same author. A genus of microscopic + Foraminifera. + + PLATIRIS. Lea. ([Greek: platus], _platus_, wide; [Greek: iris], + _iris_.) A genus including several species of Nayades, referred to + IRIDINA, Lam. The genus Platiris is divided into two sub-genera. + Iridina, species which have crenulated margins; I. Ovata, I. exotica, + Spatha, Lea; those with smooth or very slightly crenulated hinges, S. + rubeus, S. Solenoides, Mycetopus, D'Orb. Fig. 151. + + PLATYLEPAS. ([Greek: platus], _platus_, wide; [Greek: lepas], _lepas_, + rock.) _Order._ Sessile Cirripedes, Lam. _Fam._ Balanidea, + Bl.--_Descr._ Conical, depressed, consisting of six valves, each + divided internally by an angular plate jutting from the centre (like + the buttress of a wall); operculum consisting of four valves in + pairs.--_Obs._ This genus differs from Balanus, Coronula, &c. in the + internal structure of the valves. De Blainville's description of + Chthalamus partly agrees with this. Fig. 19. + + PLECTOPHORUS. Fer. ([Greek: plêktron], _plectron_, spur; [Greek: + phoreô], _phoreo_, to carry.) A genus consisting of small testaceous + appendages fixed on the posterior extremity of a species of slug. P. + corninus, fig. 260. + + PLEIODON. Conrad. IRIDINA, Lam. _Fam._ Nayades, Lam. + + PLEKOCHEILUS. Guild. AURICULA Caprella, Lam. CARYCHIUM undulatum, + Leach. (CAPRELLA, Nonnull.) This proposed genus is described as + scarcely umbilical, dextral, oval, spiral; with the spire elevated, + obtuse; the two last whorls very large, ventricose; aperture entire, + elongated; columella with a single plait; the plait concave, inflected. + Fig. 522, 523. + + PLEUROBRANCHUS. Cuv. ([Greek: Pleura], _pleura_, the side; _Branchiæ_, + gills.) _Fam._ Semiphyllidiana, Lam. Subaplysiacea, Bl.--_Descr._ + Internal, thin, haliotoid, slightly convex towards the spiral apex; + aperture entire.--_Obs._ This is a very light shell, delicately + coloured, resembling Aplysia, but differing in the integrity of the + margin. Fig. 232, P. membranaceus. + + PLEUROCERUS. Rafinesque. A genus very imperfectly described in the + "Journal de Physique" as "oval, or pyramidal; aperture oblong; outer + lip thin; inner lip truncated at the columella, which is smooth and + tortuous, not umbilicated. Operculum horny or membranaceous." De + Blainville, in giving this description, remarks that he has neither + seen the animal nor the shell of this genus, which he imagines to have + been formed from the "Paludine Coupée de M. Say." + + PLEURORYNCHUS. Phillips. ([Greek: Pleura], _pleura_, the side; [Greek: + runchos], _rynchus_, a beak.) A genus founded upon a very singular + species of CARDIUM, distinguished by the short anterior side, and the + elongation of the hinge line into auricular processes, which are + truncated at the extremities. C. Hibernicum from the Black Rock near + Dublin, which is vulgarly called Asses-hoof, and C. elongatum (Sow. + Min. Con. vol. I. 82.), form part of this genus. + + PLEUROTOMA. Lam. _Fam._ Canalifera, Lam. Siphonostomata, Bl.--_Descr._ + Fusiform, thick, in general ribbed or striated transversely; aperture + oval, terminating anteriorly in an elongated canal; outer lip thin, + with a fissure near its spiral extremity; columella smooth, nearly + straight. Found principally in tropical climates.--_Obs._ This genus, + which nearly resembles Fusus in other respects, may be known by the + notch in the outer lip. The species differ in the length of the canal. + Swainson has designated this genus a family, thus divided into genera: + Brachytoma, in the description of which he says that the spire and + aperture are of equal length, including the species strombiformis: + Pleurotoma, in which the channel is so much lengthened, as to be little + shorter than the spire: Clavatula, having the long narrow slit of + Pleurotoma, but with a very short canal: Clavicantha, having the canal + equally short, but the sinus or notch, instead of being linear and + long, is short and wide; the surface is rough, and the whorls either + coronated with prickles, or with compressed nodules resembling spines: + Tomella, which has the spire and canal fusiform, but the spire of very + few whorls, and the inner lip considerably thickened within where it + joins the outer lip. Fig. 379, 389, P. marmorata; 381, P. + Strombiformis, (Clavatula, Sw.) + + PLEUROTOMARIA. Defr. _Fam._ Turbinacea, Lam.--_Descr._ Turbinated, + spiral; aperture sub-quadrate, with rounded angles; outer lip with a + deep slit near its union with the spire.--_Obs._ This genus, which is + only known in a fossil state, abounds in inferior Oolite, Oxford clay, + and casts are found in a limestone bed in Norway. The Scissurellæ + differ in being very minute shells, and are not so trochiform as the + species of Pleurotomaria, P. reticulata, fig. 341. + + PLICACEA. Lam. A family of the order Trachelipoda, Lam. containing the + following genera: + + 1. PYRAMIDELLA. Pyramidal, with numerous whorls. Fig. 342. + + 2. TORNATELLA. Cylindrical, with few whorls. Fig. 343, 344. + + 3. RINGICULA. Margin reflected. Fig. 540, 541. + + PLICADOMUS. Sw. A sub-genus of Pupa, thus described: "spire moderate, + regular and thick, but gradually conic; the tip obtuse; aperture + perpendicular; inner lip wanting; outer lip semicircular; the margin + dilated and reflected. P. sulcata, Chem. 135, f. 1231, 1232." Sw. p. + 332. + + PLICATED. (_Plicatus_, folded.) Applied to spiral plaits on the + columella of some shells. _Ex._ Voluta, fig. 433. Also to the angular + bendings in the margins of some bivalve shells. _Ex._ Dendostrea, fig. + 181. + + PLICATULA. Lam. (_Plicatus_, folded.) _Fam._ Pectenides, Lam. + Sub-ostracea, Bl.--_Descr._ Irregular, sub-equivalve, sub-equilateral, + attached by a small part of the surface of one valve, strongly + plicated; umbones separated by a small, external ligamentary area; + hinge with two cardinal teeth in each valve, two approximate in one + valve, received between two distant in the other; cartilage placed + between the cardinal teeth; muscular impressions one in each + valve.--_Obs._ The cardinal teeth resembling those of Spondylus, + distinguish this genus from others of the Lamarckian family Pectenides. + Very few species are yet known, they are brought from the East and West + Indies and the Philippine Islands. Fossil species are found in several + of the supra-cretaceous beds. Fig. 178, P. gibbosa. + + PNEUMOBRANCHIA. Lam. The second section of the order Gasteropoda, Lam. + containing the family Limacinea, fig. 256 to 263. + + PODOPSIS. Lam. This genus appears to have been described from specimens + of a species of Spondylus, with the triangular disc broken out, so as + to present a similarly shaped foramen, which was supposed to afford a + passage for a large byssus. + + POLINICES. Montf. A genus composed of NATICA Mammilla, and other + similar species, with mammillated spires, and the umbilicus filled with + enamel. Fig. 327. + + POLLIA. Gray. TRITONIDEA, Sw. The name given by Gray was pre-occupied + by a genus of Lepidopterous Insects. + + POLLICIPES. Leach. (_Pollex_, a thumb's breadth; _pes_, a foot.) + _Order._ Pedunculated Cirripedes, Lam.--_Descr._ Conical, compressed, + consisting of numerous valves, mostly in pairs, three or four pairs + forming the principal part of the shell, and surrounded at the base by + two or three rows of smaller valves, supported on a scaly, short + pedicle.--_Obs._ This description will be found to exclude Scalpellum, + and Smilium, the valves of which are more equal. The P. Mitellus, Auct. + (fig. 37*), has been separated as a genus under the name of Mitellus by + some authors, and it is certainly very different from P. polymerus, + fig. 37, and P. cornucopia. + + POLLONTES. Montf. MILIOLA, Bl. A genus of microscopic Foraminifera. + + POLYBRANCHIATA. Bl. ([Greek: Polus], _polus_, many; _branchiæ_, gills.) + The fifth family of the order Lamellibranchiata, Bl. containing the + genera Arca, Pectunculus and Nucula, which have a series of small teeth + on the hinge. + + POLYDONTES. Montf. ([Greek: Polus], _polus_, many; [Greek: odos], + _odos_, tooth.) A species of Helix, shaped like CAROCOLLA, and having a + number of teeth in the aperture. + + POLYGONAL. Many-sided. + + POLYGONUM. Schum. ([Greek: Polus], _polus_, many; [Greek: gônia], + _gonia_, an angle.) A genus composed of species of TURBINELLA, Auct. + which have large continuous costæ, so as to present the appearance of + many-sided shells. T. polygonus, fig. 383. This generic name may be + used to include all those species of Turbinella, Auct. which have very + small folds on the columella. + + POLYGYRA. Say. A genus of Heliciform shells, characterized by the large + number of close set whorls, constituting the spire. _Ex._ P. + Septemvolvus, fig. 275, 276. + + POLYLEPAS. Bl. ([Greek: Polus], _polus_, many; [Greek: lepas], _lepas_, + rock.) SCALPELLUM, Auct. + + POLYMORPHINA. D'Orb. A genus of microscopic Foraminifera. + + POLYPHEMUS. Montf. A genus composed of species of ACHATINA, Auct. which + have elongated apertures, short spires, and an undulation in the outer + lip. P. Glans, fig. 288. + + POLYPLAXIPHORA. Bl. The second class of the sub-type Malentozoa, Bl. + containing the genus Chiton. + + POLYSTOMELLA. Lam. A genus of microscopic Foraminifera. + + POLYTHALAMACEA. Bl. ([Greek: Polus], _polus_, many; [Greek: THalamos], + _thalamos_, chambers.) The third order of Cephalophora, Bl. the shells + of which are described as straight, more or less symmetrically + convolute, divided into several chambers. The septa are sometimes, but + not always, pierced by one or more siphons. This order is divided into + the families, Orthocerata, Lituacea, Cristacea, Ammonacea, Nautilacea, + Turbinacea, Turriculacea, all of which contain genera of chambered + shells. De Blainville arranges these families according to the degree + in which the spires revolve. The first being straight, as the + Orthocerata, and the last being so closely coiled up, that the last + whorl covers the rest, as in the Nautilacea. + + POLYTHALAMIA. Lam. The first division of the order Cephalopoda, Lam. + containing the following families of chambered shells, viz. + Orthocerata, Lituacea, Cristacea, Sphærulacea, Radiolata, Nautilacea, + Ammonacea. Fig. 463 to 484. + + POLYTROPA. Sw. A genus of "Scolyminæ," Sw. thus described: + "Bucciniform; but the base narrow, and ending in a straight and + contracted, but rather short, channel; spire longer, or as long as the + aperture; exterior folliculated, or tuberculated; inner lip flattened, + as in _Purpura_; basal notch small, oblique; no internal channel; + crispata. En. Méth. 419, f. 2. Chem. 187, f. 1802. Capilla, Pennant, + pl. 72, f. 89, imbricata. Mart. 122. f. 1124. ? rugosa. Chem. f. + 1473-4." Sw. p. 305. + + POLYXENES. Montf. A genus of microscopic Foraminifera. + + POMATIA. Gesner. (Gray, Syn. B. M. p. 133.) A genus of the family of + "Cyclostomidæ," described as having "an elongated shell with reflexed + lips, and a horny spiral operculum." Also a sub-genus of Snails, + containing HELIX pomatia, Auct. (Gray's Turton, p. 135.) + + PORNUS. Humph. AMPULLARIA, Lam. + + PORCELLANA. Adanson. MARGINELLA, Auct. + + PORODRAGUS. Montf. A genus composed of species of Belemnites, placed by + De Blainville in the section characterized as swelled near the apex, + and straightened towards the base. + + POSIDONIA. Brong. A genus formed on the cast of a bivalve shell, common + on schists from Dillemberg. + + POSTERIOR. (_After_, _behind_.) The posterior or hinder part of a + bivalve shell, is that in which the siphonal tube of the animal is + placed. It is known in the shell, by the direction of the curve in the + umbones, which is from the posterior towards the anterior; also by the + ligament, which is always placed on the posterior part of the hinge, + when it exists only on one side of the umbones; and by the sinus (when + there is one) in the palleal impression, which is always near the + posterior muscular impression. In some shells, however, it is very + difficult for a learner to trace these marks; such bivalves, for + instance, as have the ligament spread out on both sides of the umbones; + such as are nearly symmetrical, and have the umbones consequently + straight, and a single muscular impression near the centre of the + valve. The Brachiopodous bivalves have a different position, with + relation to the animal, from the other bivalves, so that the hinge line + is the posterior extremity, and the part where the valves open, is the + anterior. The posterior extremity of the aperture of a spiral univalve + shell, is that nearest to the spire. In patelliform shells the anterior + and posterior extremities are distinguished by the muscular impression, + which is annular, enclosing a central disc in the inner surface of the + shell, excepting where it is interrupted by the place where the head of + the animal lies, which of course is anterior. The posterior is marked + _p._ in fig. 119, and 387. See ANTERIOR. + + POSTERO-BASAL MARGIN of a bivalve shell is the posterior side of the + margin opposite the hinge. + + POSTERO-DORSAL MARGIN is the posterior side of the hinge. + + POTAMIS or POTAMIDES. Brong. A genus of fresh-water shells resembling + Cerithium in the characters of the aperture, but which may be known + from that genus by the thick, horny epidermis with which they are + coated. P. muricata, fig. 377. (Cerithium, Sow.) We think that these + shells should be placed near MELANIA. + + POTAMOMYA. A genus of shells resembling Corbula, in every respect + except that of being inhabitants of fresh-water. Fig. 498, 499, + represents one of these fresh-water Corbulæ. + + POTAMOPHILA. Sow. ([Greek: Potamis], _potamis_, river; [Greek: + philios], _philios_, choice.) "Conques fluviatiles," Lam.--_Descr._ + Thick, equivalve, inequilateral, trigonal, covered with a greenish + brown, smooth, horny epidermis; hinge thickened, broad, with one + central, notched cardinal tooth in one valve, and two in the other, + with indistinct lateral teeth; ligament large, supported on prominent + fulcra; muscular impressions two in each valve, sub-orbicular.--_Obs._ + The name given to this shell refers to its place of abode, being found + in rivers. It is the Venus sub-viridis of some authors, although being + a fresh-water shell, and having an incrassated hinge, and a smooth, + thick epidermis, it is most distinct from that genus. It is described + by Bowdich under the name Megadesma, on account of its large ligament, + and by Lamarck under that of Galathæa, a name previously used by him + for a genus of Crustacea. P. radiata, fig. 115. Megadesma appears to be + the preferable name, since it has the right of priority over + Potamophila. It is found in Africa. + + PRIAMUS. A genus composed of ACHATINA Priamus, Lam. BUCCINUM + Stercus--Pulicum, Chemn. Conch. 9. t. 120. f. 1026-7. This shell is + ascertained to belong to a marine mollusc, having a horny operculum, + and therefore is justly considered to form a distinct genus, allied to + the Buccina and Struthiolariæ. Fig. 545. + + PRISODON. Schum. HYRIA, &c. Auct. Fig. 144. + + PRODUCED. (_Productus_, prominent.) A term applied to the spire of + univalve shells, or to any other prominent portion. + + PRODUCTA. Sow. (_Productus_, produced.) _Fam._ Brachiopoda, + Lam.--_Descr._ Equilateral, inequivalve, thick, striated; one valve + generally convex, with the margin inflected, produced; the other valve + flat, or slightly convex, with the margin reflected; hinge rectilinear, + transverse.--_Obs._ The peculiarity of this genus, from which it + derives its name, is the manner in which the anterior margins of the + valves are drawn out and overwrap each other. The genus is only known + in a fossil state. Species occur in Mountain Limestone, and Transition + Limestone of older date. P. depressa, fig. 206. + + PROSERPINA. Gray? Fig. 274, represents a small shell belonging to the + Helix tribe, to which it is believed, Mr. Gray has applied the name + Proserpina nitida. We do not know how the genus is defined. + + PROTO. Defr. A fossil shell resembling TURRITELLA, but having a spiral + band reaching to the centre of each valve. P. terebralis, Bl. + + PSAMMOBIA. Lam. _Fam._ Nymphacea, Lam.--_Descr._ Transverse, oblong, + slightly gaping at both ends; hinge with two cardinal teeth in one + valve, one in the other; ligament supported upon a prominent fulcrum; + muscular impressions two in each valve, sub-orbicular, distant; palleal + impression with a large sinus; epidermis thin.--_Obs._ The genus thus + described includes PSAMMOTÆA of Lamarck, which, according to him, only + differs in the number of teeth, and which he says are but "Psammobies + dégenerées." The difference appears to be accidental. This genus + differs from Tellina in not having a posterior fold in the margin. Fig. + 100. The species are found in temperate and tropical climates. + + PSAMMOCOLA. Bl. ([Greek: psammos], _psammos_, sand; _cola_, an + inhabitant.) A name given by De Blainville to shells of the genus + PSAMMOBIA, including PSAMMOTÆA of Lamarck. + + PSAMMOTÆA. See Lam. PSAMMOBIA. + + PSEUDOLIVA. Sw. A genus of "Eburninæ," Sw. thus described: "Shell + thick, oval, oliviform, ventricose; spire very short, acute; base with + two parallel grooves, one of which forms a notch at the base of the + outer lip; suture slightly channelled; inner lip very thick, and + turning inwards; aperture with an internal canal. Connects the + TURBINELLIDÆ with the VOLUTIDÆ. P. plumbea, Chem. 188. f. 1806, 1807." + Sw. p. 306. + + PSILOSTOMATA. Bl. The third family of Aporobranchiata, Bl. containing + no genera of shells. + + PTEROCERAS. Auct. ([Greek: Pteron], _pteron_, a wing; [Greek: keras], + _ceras_, horn.) _Fam._ Ailées, Lam.--_Descr._ Turrited, oval, + ventricose, thick, tuberculated; spire short; aperture oval, + terminating in a lengthened canal at both extremities; outer lip + thickened, expanded, produced into horn-shaped, hollow, thickened + spires, with an anterior sinus apart from the canal.--_Obs._ This + genus, containing the shells commonly called Devil's Claws, Gouty + Scorpions, Spiders, &c. is distinguished from Strombus by the + digitations of the outer lip. No fossil species are known. Fig. 405, P. + aurantiaca. + + PTEROCYCLOS. Benson. Syn. B. M. p. 133. A genus formed of species of + Cyclostoma, Auct. which have "a groove or hole at the hinder part of + the mouth." + + PTEROPODA. Lam. ([Greek: Pteron], _pteron_, a wing; [Greek: pous], + _pous_, a foot.) The first order of the class Mollusca, Lam. consisting + of molluscs whose organs of locomotion consist of a pair of wing-shaped + fins. This order contains the genera Hyalæa, Clio, Cleodora, + Spiratella, Cymbulia, and Pneumoderma. To which may be added other + genera enumerated in explanation of figures 220 to 226. They may be + thus distinguished. + + 1. ATLANTA. Shaped like Nautilus, symmetrical. Fig. 220. + + 2. SPIRATELLA. Spiral, not symmetrical. Fig. 224. + + 3. CRESEIS. Straight, thorn-shaped. Fig. 222. + + 4. VAGINULA. Straight, widened in the centre; apex pointed. Fig. + 225. + + 5. CUVIERIA. The same; apex blunt. Fig. 223. + + 6. CLEODORA. Aperture with three spines; apex recurved. Fig. 221. + + 7. HYALÆA. Vaulted, open extremity, three-cornered; apex + tridentate. Fig. 226. + + PTEROPODA. Bl. The second family of Nucleobranchiata, Bl. the shells of + which are described as symmetrical, extremely thin, transparent, + longitudinally enrolled, either forwards or backwards. The animals are + remarkable for a pair of broad, flat, natatory organs or membranaceous + fins, from which the family derives its name. It contains, in the + system of De Blainville, the genera Atlanta, Spiratella, and Argonauta, + to which may probably be added PHARETRIUM, König; ENTALIS, Defrance. + + PULLASTRA. Sow. _Fam._ Conques Marines, Lam.--_Descr._ Equivalve, ovate + or oblong, transverse, inequilateral; hinge with three diverging + cardinal teeth in each valve, notched at the terminations; muscular + impressions two in each valve; palleal impression having a large sinus; + ligament external, partly hidden by the dorsal margin.--_Obs._ This + genus includes the Venerirupes of Lamarck, and several species of his + Veneres, they are found in the sand on the shores of temperate and + tropical climates. Fig. 120, P. textile. + + PULMONOBRANCHIATA. Bl. The first order of the first section of + Paracephalophora monoica, containing the families Limnacea, + Auriculacea, and Limacinea. + + PULVINITES. Defr. (_Pulvinus_, a cushion.) _Fam._ Malleacea, + Lam.--_Descr._ Sub-equivalve, inequilateral, compressed, thin, slightly + gaping posteriorly; one valve flat, the other rather concave; hinge + linear, short, divided into perpendicular grooves; muscular impressions + two, one sub-central, the other above it, nearer the hinge.--_Obs._ + This fossil shell is imperfectly known, and it is difficult to give a + sufficient reason for separating it from Perna. It comes from the + Baculite limestone of Normandy. Fig. 170, P. Adansonii. + + PUNCTATED. (_Punctatus_, spotted or dotted.) For example, see Conus + Nussatella. Fig. 460. + + PUNCTICULIS. Sw. A sub-genus of "Coronaxis," Sw. (Conus) described in + Swainson's Malacology, page 311. + + PUNCTURELLA. Lowe. CEMORIA, Leach. + + PUPA. Auct. _Fam._ Colimacea, Lam.; Limacinea, Bl.--_Descr._ + Cylindrical, generally ribbed; spire long, obtuse, composed of numerous + slowly increasing whorls; aperture sub-quadrate, rounded anteriorly, + entire; outer lip thickened; columella plaited.--_Obs._ This genus is + composed of land shells very variable in form, differing from Bulinus + in the numerous slowly increasing whorls of the spire, and in the plicæ + on the columella, and from Clausilia in the want of a clausium. + Britain, Southern Europe, East and West Indies, Mexico, &c. P. Uva. + Fig. 291. + + PUPELLA. Sw. A sub-genus of Clausilia. Lardn. Cyclop. Malac. p. 334. + + PUPILLA. Leach. A sub-genus of Pupa, P. marginata, Auct. (Gray's + Turton, p. 196.) + + PUPINA. Vignard. MOULINSIA, Grateloup. _Fam._ Colimacea, Lam.--_Descr._ + Pupiform, sub-cylindrical; last whorl less than the preceding; surface + brilliantly polished; suture of the spire enamelled; aperture circular; + peritreme thickened; a notch at the base of the inner lip; operculum + horny, spiral.--_Obs._ The species upon which this genus was originally + founded, and described in the "Annal des Sciences Naturelles," tome 18, + p. 439, (December 1829,) is a small pupiform shell, having nothing to + distinguish it but the enamelled suture and the notch in the aperture; + characters quite insufficient in themselves for the purpose of generic + distinction; at the same time sufficient to lead M. De Ferussac to the + suspicion of its having an operculum. The next species, described by + Grateloup under the name of Moulinsia Nunezii, (Ann. Soc. Linn. Burd, + Nov. 1840), presents more remarkable characters, having the spire + turned backwards and the penultimate whorl disproportionately large. + Seven additional species have been lately brought to this country from + the Philippine Islands by Mr. Cuming. They will be described by the + author in the Zoological Proceedings for 1841, and an illustrated + monograph of the whole genus is published in the Thesaurus + Conchyliorum, Part I, by the Author. It may be observed that in one of + the new species, the notch in the peritreme almost disappears, leaving + a very slight sinus. Fig. 524, 526, 527, 528. + + PURPURA. Auct. ("_The shell-fish from which purple is taken_," Plin.) + _Fam._ Purpurifera, Lam. Entomostomata, Bl.--_Descr._ Oval or oblong, + thick; spire for the most part short, sometimes rather longer; external + surface generally sulcated, granulated, tuberculated or muricated; + aperture long, oval, somewhat dilated, emarginated anteriorly; outer + lip crenated, acute; columella flattened; operculum horny, with the + nucleus lateral, thin towards the columella.--_Obs._ True Purpuræ to be + found in the Lamarckian genera Buccinum, Ricinula, and others. They may + be generally distinguished by the flatness of the columellar lip, and + by the short canal or emargination, which is not reflected or raised, + as in Buccinum. The species are very numerous and very variable in + form, inhabiting the seas of temperate and tropical climates. The + animals secrete a purple liquor, which has been used advantageously for + dyeing; the origin of the famous Tyrian dye. Fig. 414, P. persica. + + PURPURIFERA. Lam. (_Purpura_, purple; _fero_, to carry.) A family + belonging to the second section of Lamarck's order Trachelipoda, the + shells of which are described as having a very short recurved, or + ascending canal, or else only a notch between the inner and outer lips. + The name Purpurifera has been given to the family because the animals + which it includes, and particularly the genus Purpura, contain the + colouring matter from which the ancients obtained the well known + splendid purple. This family contains the following genera. + + 1. CASSIS. Outer lip thick, reflected, denticulated, canal turned + suddenly over the back; spire short; including _Cassidea_ and + _Cypræcassis_. Fig. 410 to 412. + + 2. CASSIDARIA. Canal turned gently upwards. Fig. 407, 408. + + 3. ONISCIA. Inner lip granulated; canal short. Fig. 409. + + 4. BUCCINUM. Outer lip thickened not reflected; canal short; + including _Cyllene_ and _Phos._ Fig. 416, 421, 422, 425. + + 5. NASSA. The same, with a notch or tooth at the extremity of the + columella; including _Cyclops_. Fig. 423, 424. + + 6. DOLIUM. Swelled, grooved spirally; outer lip not reflected. Fig. + 420. + + 7. PURPURA. Aperture large; columellar lip flat; including + Tritonidea. Fig. 414, 415. + + 8. MONOCEROS. The same, with a tooth on the outer lip. Fig. 417. + + 9. CONCHOLEPAS. Patelliform; aperture as large as the shell. Fig. + 417. + + 10. RICINULA. Columellar and outer lips granulated, denticulated, + outer lip digitated; including _Tribulus_. Fig. 413. + + 11. TRICHOTROPIS. Hairs on the epidermis, along the keels. Fig. + 429. + + 12. TEREBRA. Elongated, with a spiral groove near the suture of the + whorls. Fig. 428. + + 13. BULLIA. Short; aperture wide; outer lip marginated. Fig. 427. + + 14. EBURNA. Like Buccinum, but the outer lip not thickened. Fig. + 426. + + 15. HARPA. With varices at regular intervals. Fig. 419. + + PUSIA. Sw. A sub-genus of Tiara (Mitra.) (Sw. Malac. p. 320.) + + PUSIODON. Sw. A genus of "Lucerninæ," Sw. (Helix) thus described: + "Shell flattened, smooth; the body-whorl large, and much dilated at the + aperture; spire small, flat, of three or four contracted whorls; + aperture very oblique, sinuated, or obsoletely toothed at the base of + the outer lip, which is spreading and sub-reflected; inner lip + obsolete; umbilicus open. Zonaria Chemn. 132. f. 1188. auriculata Zool. + Ill. I. pl. 6." Sw. Malac. p. 330. + + PUSIOSTOMA. Sw. A genus of the family "Columbellinæ." Sw. Thus + described: "general form of Columbella, but the outer lip is only + toothed in the middle, where it is greatly thickened; inner lip convex + between the granular teeth; punctata, E. M. 374. f. 4. mendicaria, 375. + f. 10. turturina, 314. f. 2. fulgurans. Lam." Sw. Malac. p. 313. + + PUSTULARIA. Sw. A genus of "Cypræinæ," Sw. thus described: "Shell + generally marked by elevated pustules; aperture narrow and linear; the + extremities more or less produced; the teeth continued beyond, and + frequently forming elevated striæ across the lips. P. Cicercula, P. + Globulus." Sw. Malac. p. 324. + + PYGMÆA. Humph. COLUMBELLA, Auct. + + PYLORIDEA. Bl. The ninth family of the order Lamellibranchiata, Bl. the + shells of which are described as nearly always regular, rarely + otherwise, nearly always equivalve, gaping at both extremities; hinge + incomplete, the teeth becoming gradually obsolete; two distinct + muscular impressions; palleal impression very flexuous posteriorly. + This family is divided into: Section 1. Ligament internal; Pandora, + Thracia, Anatina, Mya, Lutricola. Section 2. Ligament external; + Psammocola, Soletellina, Solen, Sanguinolaria, Solenocurtus, Solenimya, + Panopæa, Glycimeris, Saxicava, Byssomya, Rhomboides, Hiatella, + Gastrochæna, Clavagella, Aspergillum. + + PYRAMIDAL. (_Pyramidalis._) Resembling a pyramid in form. _Ex._ + Cerithium Telescopium, fig. 378. + + PYRAMIDELLA. Lam. (_A little pyramid._) _Fam._ Plicacea, Lam. + AURICULACEA, Bl.--_Descr._ Pyramidal, smooth, polished; spire long, + pointed, composed of numerous whorls; aperture small, modified by the + last whorl, rounded anteriorly; outer lip slightly expanded; columella + tortuous, with several folds. This is a genus of small, polished, + marine shells. Pyramidella Terebellum, fig. 342. + + PYRAZUS. Montf. POTAMIS, Brongniart. + + PYRELLA. Sw. A genus consisting of Turbinella Spirilla, Auct. and + similar species, having a long channel, a pyriform outline, and one + strong plait at the base of the columella, the apex of the spire is + enlarged. P. Spirillus, fig. 384. (The proper term would be Spirilla.) + + PYRIFORM. (_Pyrum_, a pear; _forma_, shape.) Shaped like a pear, i. e. + large and rounding at one end, and gradually tapering at the other. + _Ex._ Pyrula, fig. 390. + + PYRGO. Defr. A genus of microscopic Foraminifera. + + PYRGOMA. Auct. ([Greek: Purgos], _pyrgus_, a tower.) _Order_, Sessile + Cirripedes, Lam.--_Descr._ Composed of a single conical, hollow paries, + with a small aperture closed by an operculum of four valves, and + supported upon a cup-shaped base.--_Obs._ The genera into which Leach + has divided this genus are Pyrgoma, Adna, and Megatrema; his genera + Nobia and Savignium differ in having but two valves for the operculum. + Pyrgoma differs from Creusia in having the body of the shell, i. e. the + parietal cone, simple, not divided into valves. Fig. 31. + + PYRGOPOLON. De Montfort's figure of this genus appears as if it had + been drawn from the nucleus of a Belemnite. + + PYRULA. Auct. (_A little pear._) _Fam._ Canalifera, Lam. + Siphonostomata, Bl.--_Descr._ Thin, oblong, pyriform, ventricose + towards the spire, gradually tapering towards the anterior of the + aperture, spire short, consisting of few volutions; aperture wide, + terminating in a long, narrow, open, canal; columella smooth, elegantly + tortuous.--_Obs._ The above description includes all the true Fig + shells, which present a most graceful form; the contour partaking of + the peculiar curve, called by painters the line of beauty. P. Ficus, + fig. 390. + + PYRUM. Humph. PYRULA, Lam. + + QUADRATE. (_Quadratus._) Square, applied when the outline of shells is + formed by nearly straight lines meeting at right angles. + + QUADRILATERAL. Four-sided. + + QUINQUELOCULINA. D'Orbigny. A genus of microscopic Foraminifera. + + RADIATING. (_Radians._) A term applied to the ribs, striæ, bands of + colours, &c. when they meet in a point at the umbones of a bivalve + shell, and spread out towards the ventral margin.--_Ex._ The bands of + colour in Tellina radiata, fig. 105. + + RADICATED. (_Radix_, a root.) Attached, and as it were rooted by means + of a fibrous byssus. + + RADIOLATA. Lam. A family belonging to the order Cephalopoda, Lam. The + shells belonging to it are described as discoidal, with the spire + central, and the chambers radiating from the centre to the + circumference. This family contains the genera Rotalina, Lenticulina, + and Placentula. + + RADIOLITES. A genus belonging to the family of Rudistes, differing from + Sphærulites, in having both the valves more conical. + + RADIUS. Montf. A genus composed of OVULUM Volva, Auct. and other + similar species, having a long attenuated canal at each extremity. Fig. + 442. + + RADIX. Montf. A genus composed of species of LIMNÆA, having a short + spire and wide aperture.--_Ex._ L. aperta, fig. 309. + + RAMIFIED. (_Ramus_, a branch.) Branched out.--_Ex._ The varices of some + Murices, &c. + + RAMPHIDOMA. Schum. POLLICIPES, Leach. + + RAMOSE. (_Ramosus_, branched.) Spread out into branches. _Ex._ Murex + inflatus, fig. 395. + + RANELLA. Auct. (_Rana_, a frog.) _Fam_. Canalifera, _Lam._ + Siphonostomata, Bl.--_Descr._ Oval or oblong, depressed, thick, with + two rows of continuous varices, skirting the outline, one on each side; + spire rather short, pyramidal, acute, aperture oval, terminating in a + canal at each extremity; outer lip thickened within, crenulated, or + denticulated, forming an external varix; inner lip spread over a + portion of the body whorl.--_Obs._ The shells composing this + well-defined genus, are for the most part covered with tuberculations, + and granulations, and from the colour and squat shape of some species, + have been likened to frogs. The Ranellæ are mostly inhabitants of the + East Indian seas. The few fossil species known, occur in the tertiary + beds. The two continuous rows of varices skirting the spire, + distinguish this genus from Triton, which it nearly approaches, and + into which some species run by imperceptible gradations. Fig. 393, 394. + Many new species were brought to this country by Mr. Cuming, and are + represented in parts 84, 85, 88, 89, 92, 93, of the author's + Conchological Illustrations. + + RANGIA. Desmoulins. GNATHODON, Gray. + + RAPANUS. Schum.? A genus consisting of species of PYRULA, Auct. which + are thin, much inflated, with short canals. Fig. 389, P. papyracea. + + RAPELLA. Sw. A genus of "Pyrulinæ," Sw. thus described: "Shell + ventricose, generally thin, almost globose; the base suddenly + contracted, and forming a short canal, the channel almost obsolete; + umbilicus large, partly concealed by the inner lip. R. papyracea. En. + Méth. 436, f. 1." Sw. p. 307. RAPANUS, Schum. Fig. 389. + + RAPHANISTER. Montf. A species of madrepore, described as a shell. + + RAPUM. Humph. TURBINELLA, Lam. + + RAZOR SHELL. A common name by which shells of the genus Solen, are + known in the market. + + RECTILINEAR. (_Rectus_, right; _linea_, a line.) In a straight line. + _Ex._ The hinge of Byssoarca Noæ, fig. 132. + + RECURVED. (_Re_, back; _curvo_, to bend.) Turned backwards; the term, + when applied to symmetrical conical univalves, is used to signify that + the apex is turned towards the posterior margin, as in Emarginula, fig. + 241. + + REFLECTED. (_Reflected_, to fold back.) Turned, or folded backwards. + _Ex._ The edge of the outer lip in Bulinus, fig. 282, is _reflected_, + while that of Cypræa, fig. 445 to 450, is _inflected_. + + REMOTE. (_Remotus_, distant.) Remote lateral teeth in a bivalve shell, + are those that are placed at a distance from the cardinal teeth. _Ex._ + The lateral teeth of Aphrodita, (fig. 123.) are remote; those of Donax, + (fig. 108) are near. + + RENIELLA. Sw. A sub-genus of Malleus. Lardn. Cyclop. Malac. p. 886. + Gray states it to be only a distorted specimen of Vulsella, Syn. B. M. + p. 145. + + RENIFORM. (_Ren_, a kidney; _forma_, shape.) Shaped like a kidney. + _Ex._ The aperture of Ampullaria, fig. 318. + + RENULINA. Lam. A genus of microscopic Foraminifera. + + REOPHAX. Montf. A genus of microscopic Orthocerata, Bl. + + REPENT. (_Repens_, creeping.) A term applied to those shells, which, + being attached by the whole length of their shell, give the idea of + creeping or crawling. _Ex._ Vermilia, fig. 7. + + RETICULATED. (_Reticulatus._) Resembling net-work. + + RETIFERA. Bl. The first family of the order Cervicobranchiata, Bl. + containing the genus Patella. + + REVERSED or SINISTRAL SHELLS, are those in which the aperture is on the + left side of the shell, while it is held with the mouth downwards, and + towards the observer. _Ex._ Balea, fig. 296. Attached bivalves are said + to be reversed, when the left valve is free, instead of the right; a + circumstance which sometimes occurs in Chama and Ostrea. + + RHEDA. Humph. HYALÆA, Lam. + + RHINOCLAVIS. Sw. A genus of "Cerithinæ," Sw. thus described: "channel + curved backwards, in an erect position; inner lip very thick, with a + tumid margin; pillar generally with a central plait; operculum + ear-shaped; lineatum. En. M. 443, fig. 3, Vertagus. Ib. f. 2, + subulatum. Lam. No. 23, fasciatum. Mart. 157, f. 1481. obeliscus, En. + Méth. 443, f. 4; aluco, Ib. f. 5, (Aberrant,) semi-granosum. Ib. 443, + f. 1, asperum. Mart. 157, f. 1483." + + RHINOCURUS. Montf. A genus of microscopic Foraminifera. + + RHINODOMUS. Sw. A genus of "Scolyminæ," Sw. thus described: No internal + groove; shell clavate; the spire longer than, or equal with the + aperture; the whorls with ridges or longitudinal varices, and rendered + hispid by transverse grooves; inner lip wanting; pillar with a terminal + fold; aperture striated; outer lip with a basal sinus. R. senticosus, + Chem. tab. 193. f. 1864-1866. + + RHIZORUS. Montf. A genus described from a microscopic shell, appearing + to be a cylindrical Bulla. + + RHODOSTOMA. Sw. A sub-genus of "Turbininæ," Sw. p. 344. + + RHOMBOIDAL. ([Greek: rhomboeidos], _rhomboeidus_.) Having a rhombic + form, i. e. four-sided; two sides meeting at acute, two at obtuse, + angles. Conchologists are not very strict in the application of this + term, for, indeed, a perfect rhomboidal figure could not be found among + all the testaceous productions of the sea. + + RHOMBOIDES. Bl. A genus described as resembling Byssomya in the shell, + but differing in the animal. MYTILUS rugosus, Gmelin. HYPOGÆA barbata, + Poli. + + RHOMBUS. Montf. ([Greek: rhombos], _rhombos_, a rhomb.) A genus + consisting of species of CONUS, having a rhomboidal or quadrilateral + form and a coronated spire. _Ex._ Conus nocturnus, fig. 459. + + RICINULA. Lam. (Resembling the seed-vessel of the _Ricinus_.) _Fam._ + Purpurifera, Lam. Entomostomata, Bl.--_Descr._ Sub-ovate, thick, + tuberculated; spire short; aperture narrow, terminating anteriorly in a + short canal; outer-lip thickened, denticulated within, digitated + without; columellar lip spread over a portion of the body whorl, and + granulated.--_Obs._ This interesting genus is composed of some neat + little shells allied to Purpura, from which they are distinguished by + the finger-like branching of the outer lip, and the granulations of the + columella. Fig. 413, R. Horrida. + + RIGHT. See DEXTRAL. + + RIMULA. Defr. A genus consisting of a minute species of EMARGINULA, + Auct. which has a fissure near the margin, but not reaching it. R. + Blainvillii, fig. 243. + + RIMULINA. D'Orbigny. A genus of microscopic Foraminifera. + + RINGICULA. Deshayes. A genus founded on Auricula ringens of Lamarck and + several small fossils, resembling in some respects Pedipes of Adanson; + they would belong to Tornatella, were it not for the lips being + thickened and marginated, fig. 540, A. ringens. + + RISSOA. Freminville. _Fam._ Ellipsostomata, Bl. Melaniana, + Lam.--_Descr._ Oblong, turrited, acuminated; spire long, consisting of + numerous whorls; aperture round or oval, pointed posteriorly, dilated + anteriorly; outer lip slightly thickened, emarginated, operculum + horny.--_Obs._ The Rissoæ are small white, marine shells, considered by + some authors as resembling Melaniæ, but placed by Sowerby near the + Scalariæ. They are principally from the shores of the Mediterranean, + and are also very abundant on the British shores, as well as the East + and West Indian. Fig. 346, R. reticulata. + + ROBULUS. Montf. A genus of microscopic Foraminifera. + + ROLLUS. Montf. A genus composed of CONUS Geographus, Auct. fig. 462, + and other species, rather cylindrical in form, and having a coronated + spire. + + ROSALINA. D'Orb. A genus of microscopic Foraminifera. + + ROSTELLARIA. (From _rostrum_, a beak.) _Fam._ Alatæ, Lam. + Siphonostomata, Bl.--_Descr._ Turrited, fusiform, thick, smooth or + ribbed; aperture oval, terminating anteriorly in a long canal, + posteriorly in a channel running up the spire; outer lip dilated, + thickened, sometimes digitated, running up all or part of the spire, + with a sinus near the anterior canal; inner lip smooth, spread over + part of the body whorl and of the spire. The Red Sea and the Indian + Ocean produce the few known species of this genus.--_Obs._ HIPPOCHRENES + is the name given by De Montfort, to those fossil species which have + the outer lip simple and very much dilated. R. curvirostrum, fig. 412. + APORRHAIS is a name given to another proposed genus, composed of + Rostellaria pes-pelecani, Auct. fig. 404. and similar species. + + ROSTRATED. (From _rostrum_, a beak.) Having one or more protruding + points, as Tellina rostrata. + + ROTALIA. Lam. A genus of microscopic Foraminifera. The same as + Rotalites of De Montfort. + + ROTELLA. Lam. (_A little wheel._) _Fam._ Turbinacea, Lam.--_Descr._ + Orbicular, generally smooth, shining; spire conical, depressed, short; + aperture subtrigonal; outer lip thin, angulated near the centre; inner + lip spread over the surface of the whorls, forming a thickened disc. + Operculum horny, orbicular, spiral, with numerous whorls.--_Obs._ The + pretty little shells thus described are found in seas of tropical + climates. They are distinguished from other genera of the family by + their lenticular form and the orbicular callosity of the under surface. + Fig. 357, R. vestiaria. + + RUDISTES. Lam. A family of the order Conchifera Monomyaria, Lam. the + shells of which are described as irregular, very inequivalve, without + distinct umbones; the ligament, hinge and animal entirely unknown. The + shells contained in this family may be thus distinguished. + + 1. CALCEOLA. Large valve conical; attached by a flat space between + the umbones, which form the extremities of the shell. Fig. 194. + + 2. HIPPURITES. Large valve cylindrical, with two internal lobes or + varices. Fig. 198. + + 3. SPHÆRULITES. Large valve attached, including _Radiolites_. + Birostrites is proved to be the cast of a Sphærulites. Fig. 193, + 196. + + 4. HIPPONYX. Flat valve attached, upper valve conical. Fig. 199, + 200. + + RUDISTES. Bl. The second order of the class Acephalophora, Bl. + containing the genera Sphærulites, Crania, Hippurites, Radiolites, + Birostrites and Calceola. + + RUDOLPHUS. Lam. MONOCEROS, Auct. + + RUFOUS. Reddish brown. + + RUGOSE. Rough, rugged. + + RUPELLARIA. Fl. de Belvue. An unfigured shell placed by De Blainville + in a division of the genus Venerirupis. + + RUPICOLA. Fl. de Belvue. A shell described by De Blainville as an + equivalve, terebrating species of ANATINA. A. rupicola, Lam. + + SABINEA. A genus of shells resembling small species of LITTORINA, as L. + Ulvæ, &c. of our shores. + + SADDLE OYSTER. PLACUNA Sella, so called on account of a resemblance in + shape to a saddle; the part near the umbones being flat, and the + ventral margins being turned up in a sort of fluting or peak. + + SAGITTA. (_An arrow._) An ancient name for Belemnites. + + SALIENT. (_Saliens._) Jutting out, prominent. + + SALPACEA. Bl. The second family of the order Heterobranchiata, Bl. + containing no genera of shells. + + SANDALINA. Schum. CREPIDULINA, Lam. A genus of microscopic + Foraminifera. + + SANGUINOLARIA. Lam. (_Sanguis_, blood.) _Fam._ Nymphacea, Lam. + Pyloridea, Bl.--_Descr._ Equivalve, inequilateral, transverse, + sub-ovate, rounded anteriorly, sub-rostrate posteriorly, compressed, + thin, covered with a shining epidermis, gaping at the sides; hinge with + two cardinal teeth in each valve, and an external ligament supported + upon a prominent fulcrum; muscular impressions two in each valve, + lateral, irregular, palleal impressions with a large sinus.--_Obs._ + This description is made to exclude some of Lamarck's species of + Sanguinolaria, such as S. occidens, S. rugosa, which are Psammobiæ; and + to include others which he has left out. The Sanguinolariæ are + sub-rostrated posteriorly, while the Psammobiæ are sub-quadrate and + have a posterior angle. Fig. 98, S. rosea. Sandy shores of tropical + climates. + + SARACENARIA. Defr. A genus of microscopic Foraminifera. + + SAVIGNIUM. Leach. A genus of Sessile Cirripedes, described as composed + of four valves soldered together, and a convex bivalve operculum; the + ventral and posterior valve on each side being soldered together, in + other respects resembling PYRGOMA. Fig. 30. + + SAXICAVA. Fl. de Belvue. Journ. de Ph. an. 10. (_Saxum_, a stone; + _cava_, a hollow.) _Fam._ Lithophagidæ, Lam. Pyloridea, Bl.--_Descr._ + Transverse, irregular, generally oblong, inequilateral, sub-equivalve, + gaping anteriorly; ligament external; muscular impressions two, + lateral; palleal impression interrupted, not sinuated; hinge, when + young with sometimes two or three minute, obtuse, generally indistinct, + cardinal teeth; which become obsolete when full grown.--_Obs._ Several + genera have been founded only upon the difference between the young and + old shell of the same species of this genus. The Saxicavæ are found in + the little hollows of rocks; in cavities on the backs of oysters, of + roots of sea-weeds, &c. in northern and temperate climates. S. rugosa, + fig. 94. + + SCABRICULA. Sw. A sub-genus of Mitræ, consisting of species which have + a roughened external surface, &c. Sw. Malac. p. 319. + + SCABROUS. Rough. + + SCALA. Klein. SCALARIA, Auct. + + SCALARIA. Auct. _Fam._ Scalariana, Lam. Cricostomata, Bl.--_Descr._ + Turrited, oval or oblong; spire long, composed of rounded, sometimes + separate whorls, surrounded by regular concentric ribs; aperture oval, + peristome reflected continuous, entire.--_Obs._ The typical species of + this genus, commonly called the Wentletrap, (S. pretiosa) is celebrated + for the beautiful appearance caused by the numerous ribs encircling the + whorls, and formerly produced an immense price in the market. It is + brought from China. There are many smaller species, some of which are + equally elegant. Fig. 351, S. Pallasii, Kiener. + + SCALARIANA. Lam. A family belonging to the first section of the order + Trachelipoda, Lam. The shells belonging to it are described as having + the inner and outer lips continuous, without a canal, emargination, or + other division. In this respect the family is stated to differ from the + Turbinacea, and is therefore separated. The genera may be distinguished + as follows:-- + + 1. VERMETUS. Irregularly twisted, like Serpula. Fig. 345. + + 2. EULIMA. Pyramidal; apex contorted; including _Bonellia_. Fig. + 347, 348. + + 3. RISSOA. Pyramidal, straight, consisting of few whorls. Fig. 346. + + 4. SCALARIA. With external varices. Fig. 351. + + 5. CIRRUS. Trochiform. Fig. 349. + + 6. ENOMPHALUS. Orbicular. Fig. 350. + + 7. DELPHINULA. Few whorls, rapidly increasing. Fig. 352. + + SCALLOP. The common name for shells of the genus Pecten, the larger + species of which were worn by pilgrims to the Holy Land in the time of + the Crusades. + + SCALPELLUM. Leach. (A little knife or lancet.) _Order_, Pedunculated + Cirripedes, Lam.--_Descr._ Flat, quadrated, acuminated, composed of + thirteen valves, one dorsal, arcuated; one pair apicial, acuminated; + one pair ventral; two pair lateral, small, sub-quadrate; pedicle + scaly.--_Obs._ This genus and _Smilium_, are the only Pedunculated + Cirripedes which have thirteen valves; in the latter genus, which we + think should at any rate be united to this, the valves are somewhat + differently placed, and the pedicle is said to be smooth. Fig. 35, + Scalpellum vulgare. British. + + SCAPHA. Klein. (_A boat._) NAVICELLA, Auct. + + SCAPHANDER. Montf. BULLA lignaria, Auct. Fig. 251. + + SCAPHELLA. Sw. A genus of the family "Volutinæ," Sw. thus described: + "Shell smooth, almost polished; outer lip thickened internally; suture + enamelled; lower plaits the smallest; apex of the spire various: 1. + fusiformis. Sw. Bligh. Cat. 2. undulatus. _Ex._ Conch. pl. 27. 3. + Junonia, _Ex._ Conch. pl. 33. 4. stromboides. 5. papillosa. Sw. Sow. + gen." Sw. Malac. p. 318. + + SCAPHITES. (_A boat._) _Fam._ Ammonacea, Lam. and Bl.--_Descr._ + Convolute, chambered, closely related to the Ammonites, from which it + differs in the last whorl being eccentrically straightened, and + lengthened, and again incurved towards the extremity. Only known in a + fossil state. Fig. 481, S. æqualis. + + SCAPHULA. Sw. A genus of "OLIVINÆ," Sw. thus described: "Spire very + short, thick, obtuse, and not defined; aperture very wide, with only + two or three oblique plaits at the base. Sw. patula, _Sow._ Tank. Cat. + 2331. (_b._)" (Sw. p. 322.) + + SCARABUS. Montf. (_Scarabæus_, a kind of beetle.) _Fam._ Colimacea, + Lam. Auriculacea, Fer.--_Descr._ Oval, somewhat compressed, smooth, + with slightly raised varices; spire equal in length to the aperture, + pointed, consisting of numerous whorls; aperture ovate, rounded + anteriorly, pointed posteriorly, modified by the last whorl; outer lip + sub-reflected, with several prominent folds on the inner edge; inner + lip spread over a portion of the body whorls, with several prominent + folds.--_Obs._ The shells of this genus are found like Auriculæ, in + marshy places. C. imbrium is said to have been found on the tops of + mountains, by Captain Freycinet. Fig. 299*, S. imbrium. + + SCHIZODESMA. Gray. A genus composed of species of MACTRA, Auct. with + the ligament placed in an external slit. Fig. 8, M. Spengleri. + + SCISSURELLA. D'Orbigny. (_Scissus_, cut.) _Fam._ Turbinacea, + Lam.--_Descr._ Sub-globose, umbilicated, with a spiral groove + terminating at the margin of the outer lip in a slit; spire short; + aperture oval, modified by the last whorl; outer lip sharp, with a deep + slit near the spire. Recent on the coasts of Britain; fossil in the + Calcaire-grossièr.--_Obs._ This genus, consisting of small shells, is + known from Pleurotomaria by the shortness of the spire; the latter + genus being trochiform. Fig. 340, S. elatior. + + SCOLYMUS. Sw. A genus of the family "Scolyminæ." Sw. (Turbinella) thus + described: "Sub-fusiform, armed with foliated spines; spire shorter; + pillar with distinct plaits in the middle." The species enumerated are, + "cornigerus, pugillaris, Globulus, Rhinoceros, ceramicus, Capitellum, + umbilicaris, mitis." Sw. Malac. p. 304. + + SCORTIMUS. Montf. A genus of microscopic Foraminifera. + + SCROBICULARIA. Schum. Species of LUTRARIA, Act. of a rounded shape. + LIGULA, Leach. + + SCROBICULATED. (_Scrobiculus_, a little ditch or furrow.) Having small + ditches or furrows marked on the surface. + + SCUTELLA. Brod. (_Scutellum_, a little shield.) _Fam._ Phyllidiana, + Lam.--_Descr._ Shaped like Ancylus, pearly within; apex posteriorly + inclined, central, involute; muscular impressions two, oblong, ovate, + lateral; aperture large, ovate.--_Obs._ This genus is intermediate + between Ancylus and Patella; while in the aspect of the beak, the + observer is reminded of Navicella. + + SCUTIBRANCHIATA. Bl. (_Scutum_, a shield; _branchiæ_, gills.) The third + order of Paracephalophora Hermaphrodita, Bl. containing animals with + patelliform, but not symmetrical shells, and divided into the families + Otidea and Calyptracea. + + SCUTUM. Montf. (_A shield._) PARMOPHORUS ELONGATUS, Lam. + + SECURIFORM. (_Securis_, an axe; _forma_, shape.) Hatchet-shaped. _Ex._ + Pedum, fig. 179. + + SEDENTARY ANNELIDES. Lam. The third order of the class Annelides, Lam. + distinguished from the two other orders by the circumstance of the + animal being enveloped by a shelly tube which it never entirely leaves. + The order is divided into the families Dorsalia, Maldania, Serpulacea, + and Amphitrites. Fig. 1 to 13. + + SEA DATE. The common name for PHOLAS Dactylus in the market, given to + it on account of its cylindrical shape. Fig. 35. + + SEGMENTINA. Flem. NAUTILUS Lacustris, Montagu. Test. Brit. Planorbis + nitidus, Drap. tab. 2. Fig. 17 to 19. + + SEMICORDATE. Half heart-shaped. + + SEMIDISCOIDAL. Forming the half of a circular disc. + + SEMILUNAR. Half moon-shaped. + + SENECTUS. Humph. A genus of "Senectinæ," thus described by Swainson: + "Imperforate; the base produced into a broad flat lobe, spire rather + elevated and pointed; the whorls convex; aperture perfectly round; not + more oblique than _Helix_; inner lip entirely wanting, imperialis. + Mart. 180. f. 1790. marmoratus. l. M. 448. f. 1." Sw. p. 348. + + SEMIPHYLLIDIANA. Lam. The second family of the order Gasteropoda, Lam. + the genera of which are distinguished as follows:-- + + 1. UMBRELLA, round, flat; apex central, muscular impression not + interrupted. Fig. 233. + + 2. PLEUROBRANCHUS, apex lateral, sub-spiral. Fig. 232. + + SENOCLITA. Schum. CINERAS, Leach. + + SEPTARIA. Lam. See TEREDO. + + SEPTUM. (Lat.) An enclosure, applied to the thin plate of Crepidula, + fig. 239; also to the plates dividing the chambers of multilocular + shells. + + SERAPHS. Montf. TEREBELLUM convolutum, Lam. Fig. 451. + + SERPULA. Auct. (_A little serpent._) _Fam._ Surpulacea, Lam.--_Descr._ + Tubular, narrow, pointed at the apex, gradually widening towards the + aperture, attached irregularly, sometimes spirally, twisted, + imbricated; keeled or plain; aperture generally round, with the edge + simple, or angulated by the termination of external ribs or + keels.--_Obs._ This description is intended to include the genera + Serpula, Spirorbis, Vermilia, Galeolaria, &c. The Serpulæ abound in all + seas, on rocky shores, at any time covered by water, attached to any + kind of marine substance, whether moveable or stationary. The fossil + species occur in almost all tertiary strata. Fig. 4 to 7. + + SERPULACEA. Lam. The fourth family of the order Sedentary Annelides, + Lam. containing the following genera of tubular, irregular shells. + + 1. SERPULA, attached by a small portion of the shell. Fig. 4. + + 2. SPIRORBIS, attached by the whole length, coiled. Fig. 5. + + 3. Galeolaria, with the open extremity raised, and the aperture + tongue-shaped. Fig. 6. + + 4. VERMILIA, attached by the whole length, straight or waved. Fig. + 7. + + 5. SPIROGLYPHUS, which hollows a bed in the body to which it is + attached. Fig. 8. + + Sowerby. (Genera of Shells, published at 50, Great Russell + Street, Bloomsbury,) gives satisfactory reasons for re-uniting the + whole of the preceding under the name SERPULA. + + 6. MAGILUS, which burrows in coral; outer lip reflected. Fig. 9 to + 10. + + 7. LEPTOCONCHUS, outer lip reflected. Fig. 11. + + 8. STYLIFER, spiral, thin, globular, living in Starfish. Fig. 12, + 13. + + The three last genera should certainly find some other place in + the system. + + SESSILE CIRRIPEDES. Lam. (_Sessilis_, low, dwarfish.) An order of + Cirripedes, consisting of those which are attached by the base of the + shells, containing the genera Tubicinella, Balanus, Coronula, Acasta, + Pyrgoma, Creusia. To which may be added some other genera enumerated in + explanation of figures 14 to 33. The shells of the Sessile Cirripedes + consist of two different sets of valves: 1st. The _parietal_ valves, or + pieces arranged in a circle, side by side, around the body of the + animal, (an arrangement designated _coronular_ by De Blainville.) 2nd. + The _opercular_ valves, or pieces placed so as to enclose the aperture. + Between those opercular valves the ciliæ protrude which characterize + the class. Besides these two sets of valves, there is generally a + shelly plate, serving as a sort of foundation to the rest. The Sessile + Cirripedes may be thus arranged. + + 1. TUBICINELLA. Six parietal valves, tube-shaped, opercular valves + perpendicular. Fig. 14. + + 2. CORONULA. Six parietal valves, opercular valves horizontal. Fig. + 15, 16, 17, 18. + + These two genera fix themselves in the skin of the Whale. The + latter has been divided into the genera Chelonobia, Cetopirus, + Diadema, and Chthalamus. + + 3. PLATYLEPAS. Valves divided, each having a prominent internal + plate. Fig. 19. + + 4. CLITIA. Parietal valves four, opercular valves two, valves + dove-tailed into each other. Fig. 20. + + 5. ELMINEUS. Parietal valves four, opercular valves four. Fig. 22. + + 6. CONIA. Parietal valves four, thick and porous at the base. Fig. + 21. + + 7. OCTOMERIS. Parietal valves eight. Fig. 24. + + 8. CATOPHRAGMUS. Parietal valves numerous, irregular. Fig. 23. + + 9. BALANUS. Parietal valves six; opercular valves four, placed + against each other conically in pairs. This genus has been divided + into Acasta, Conoplea, Chirona, and Balanus. Fig. 25, 26, 27. + + 10. CREUSIA. Parietal valves four, supported on the edge of a + funnel-shaped cavity. Fig. 28. + + 11. PYRGOMA. Paries simple, supported on a cavity. This genus has + been divided into the genera Nobia, Savignium, Pyrgoma, Adna, + Megatrema, and Daracia. Fig. 29 to 33. + + SETIFEROUS. Hairy. + + SHANK SHELL. The vulgar name for the shell designated Murex Rapa. It is + used in Ceylon for ornamental purposes. + + SIDEROLITES. Montf. A genus of microscopic Foraminifera. + + SIGARETUS. Lam. _Fam._ Macrostomata, Lam.--_Descr._ Suborbicular, + oblique, haliotoid, thick; spire depressed, consisting of two or three + rapidly increasing whorls; aperture wide, entire, modified by the last + whorl, the width exceeding the length; columella tortuous; inner lip + spread thinly over part of the body whorl; epidermis thin.--_Obs._ This + genus is distinguished from Natica, by the width of the aperture, and + the absence of the umbilical callosity. It may be known from Stomatia, + and Stomatella, by the texture, which in Sigaretus, is never pearly as + in Stomatia, the former being partly an internal shell. Fig. 334, S. + concavus. Mostly brought from tropical climates. + + SILIQUA. Megerle. (A husk, or pod.) LEGUMINARIA, Schum. A genus + composed of species of SOLEN, Auct. which have an internal rib. Fig. + 51, Solen radiatus. + + SILIQUARIA. Brug. _Fam._ Cricostomata, Bl. Dorsalia, Lam.--_Descr._ + Tubular, rugose, spiral near the apex, irregularly twisted near the + aperture, with a longitudinal fissure radiating from the apex, and + proceeding through all the whorls and sinuosities of the tube.--_Obs._ + This genus was included in Serpula by Linnæus, from which, however, it + is distinguished by the longitudinal slit, fig. 1. S. anguina. The + recent species are found in the sponges with siliceous spiculæ, in the + Mediterranean; the fossils in tertiary beds. + + SIMPLE. (_Simplex_, lat.) Single, entire, uninterrupted, undivided. + + SIMPLEGAS. Mont. 1, 83. (_Simplex_, simple; [Greek: gastêr], _gaster_, + belly.) A genus described by De Blainville, as being discoidal, and + having the spire uncovered like AMMONITES, but having the chambers + divided, by simple septa, like Nautilus.--_Obs._ The septa of the shell + named Simplegas by De Montfort, are evidently sinuous, according to his + figure. Fig. 475, S. sulcata. + + SINISTRAL. (_Sinister_, left.) On the left side. A sinistral shell is a + _reversed_ one. The sinistral valve of a bivalve shell may be known, by + placing the shell, with its ligamentary or posterior part towards the + observer; the sides of the shell will then correspond with his right + and left side. + + SINUOUS. Winding, serpentine. The septa of Ammonites are sinuous. The + muscular impression of the mantle, or palleal impression of some + bivalve shells, is sinuated near the posterior muscular impression. + + SINUS. (_Sinus_, a winding, or bay.) A winding or tortuous excavation. + The sinus in the outer lip of Strombus, fig. 406; and that in the + muscular impression of Venus, will be indicated by the letter _s_. + + SIPHON. ([Greek: Siphon], siphon.) A pipe, or tube. A shelly tube + passing through the septa of chambered shells. It is said to be + _dorsal_, _central_, or _ventral_, according to its situation near the + outer, or inner parts of the whorl. See Introduction. + + SIPHONAL SCAR. The name applied by Mr. Gray, to the opening or winding + sinus in the palleal impression of a bivalve shell, in the place where + the siphonal tube of the animal passes. + + SIPHONARIA. Sow. ([Greek: Siphon], siphon.) _Fam._ Phyllidiana, Lam. + Patelloidea, Bl.--_Descr._ Patelliform, depressed, inclining to oval, + ribbed; apex nearly central, obliquely inclining towards the posterior + margin; muscular impression partly encircling the central disc, but + interrupted in front, where the head of the animal reposes, and at the + side by a siphon, or canal passing from the apex to the margin.--_Obs._ + This siphon, which is in some species very distinct, serves to + distinguish this genus from Patella. S. Sipho, fig. 231*. + + SIPHONOBRANCHIATA. Bl. (_Siphon_, and _Branchiæ_, gills.) The first + order of Paracephalophora Dioica, Bl. divided into the families + Siphonostomata, Entomostomata, and Angiostomata. + + SIPHONOSTOMA. Guild. A sub-genus of Pupa, consisting of several + elongated species, which have the aperture detached from the whorls; + such as P. costata, and fasciata. + + SIPHONOSTOMATA. Bl. ([Greek: Siphon], _siphon_; [Greek: stoma], + _stoma_, mouth.) The first family of Siphonobranchiata, Bl. the shells + of which are extremely variable in form, but always have a canal or + notch at the anterior extremity of the aperture. This family partly + answers to the Canalifera of Lamarck and the genus Murex in the system + of Linnæus. It contains the genera Pleurotoma, Rostellaria, Fusus, + Pyrula, Fasciolaria, Turbinella, Columbella, Triton, Murex, Ranella, + and Struthiolaria. + + SIPHUNCLE. (Siphunculus.) A small siphon. + + SISTRUM. Montf. RICINULA, Auct. fig. 413. + + SKENEA. _Flem._ A genus including some species of EUOMPHALUS and + CIRRUS. + + SMILUM. Leach. _Fam._ Pedunculated Cirripedes.--_Descr._ Thirteen + pieces, ten of which are in pairs, lateral, subtriangular; one + posterior dorsal, linear; all smooth; peduncle hairy.--_Obs._ This + genus is distinguished from Pentelasmis, by the number of its valves, + and from Scalpellum, by the hairy peduncle. S. Peronii, fig. 36. + + SNAIL. The common garden Snail, so destructive to our vegetables, + belongs to the genus Helix. The water snail, found in ponds, is + Planorbis. + + SOL. Humph. A genus consisting of several species of the genus Trochus, + and corresponding with the sub-genus Tubicanthus, Sw. Malac. Fig. 349. + + SOLARIUM. Auct. (_A terrace, or gallery_.) _Fam._ Turbinacea, Lam. + Goniostomata, Bl.--_Descr._ Discoidal beneath, conical above, with a + wide umbilicus, the spiral margin of which is angulated and crenulated; + aperture trapezoidal; peritreme thin, sharp; columella straight; + operculum horny, subspiral.--_Obs._ The Solarium Perspectivum, is + commonly called the Staircase Trochus, from the angulated edges of the + whorls being seen through the umbilicus, which reaches to the apex, and + presents the appearance of a winding gallery. The species are not + numerous, they belong to tropical climates. A few fossil species occur + in the tertiary formations. Fig. 353, S. Perspectivum. + + SOLDANIA. D'Orb. A genus of microscopic Foraminifera. + + SOLEN. Auct. (_A kind of shell-fish_, Plin.) _Fam._ Solenacea, Lam. + Pyloridea, Bl.--_Descr._ Bivalve, transversely elongated, + sub-cylindrical, equivalve, very inequilateral, gaping at both + extremities, umbones terminal, close to the anterior extremity; hinge + linear, with several small cardinal teeth, and a long, external + ligament; muscular impressions distant, anterior tongue-shaped, placed + behind the cardinal teeth, posterior irregular, sub-ovate; palleal + impression long, bilobed posteriorly.--_Obs._ The above description of + the genus Solen, is framed so as to admit only those species which are + commonly called Razor Shells, with the umbones terminal, and the + anterior muscular impression behind them. They are found buried deep in + the sand, in a perpendicular position, their situation being pointed + out by a dimple, on the surface. They are abundant in temperate + climates. Some of the Lamarckian Solenes will be found in the genus + Solenocurtus, Bl. Fig. 60, 61. + + SOLENACEA. Lam. A family of the order Conchifera, Dimyaria Lam. The + shells belonging to it are described as transversely elongated, + destitute of accessary pieces, gaping only at the lateral extremities; + ligament external.--The genera may be thus distinguished. + + 1. SOLEN. Razor shells, truncated at the extremities. Fig. 60. + + 2. PANOPÆA. Broad, with prominent tooth. Fig. 65, 66. + + 3. SOLENOCURTUS. Rounded at the extremities, with internal bar. + Fig. 61. + + 4. SOLENIMYA. No teeth, epidermis over-reaching the shell. Fig. 68. + + 5. GLYCIMERIS. Thick, fulcrum of the ligament prominent. Fig. 67. + + 6. LEPTON. Flat, scale-shaped. Fig 62. + + 7. NOVACULINA. Umbones nearly central; covered by a thin epidermis. + Fig. 63. + + 8. GLAUCONOME. Oval, margins close. Fig. 64. + + SOLENELLA. Sow. (_Solen._) _Fam._ Arcacea, Lam.--_Descr._ Oval, + equivalve, subequilateral, compressed, covered with a thin, shining, + olive-green epidermis; hinge with three or four anterior, and numerous + sharp posterior lateral teeth, arranged in a straight line; muscular + impressions two, lateral; palleal impression with a large sinus; + ligament external, prominent, elongated.--_Obs._ This genus partakes of + the characters of the genus Nucula, and of the family Solenacea. A few + specimens of the only species known (S. Norrisii, fig. 138.) were + dredged by Mr. Cuming at Valparaiso. + + SOLENIMYA. Lam. (Solen and Mya.) _Fam._ Mactracea, Lau. Pyloridea, + Bl.--_Descr._ Equivalve, inequilateral, transversely oblong, rounded at + the extremities with the umbones near the posterior side, covered with + a shining brown epidermis extending beyond the edges of the shell; + hinge without teeth; ligament partly internal, placed in the margin of + an oblique, flattish, posterior rib; muscular impressions two, distant, + lateral. From the Mediterranean, Australian, and Atlantic + Oceans.--_Obs._ Solenimya differs from Solenocurtus and the true + Solens, in having the posterior side of the shell the shortest; in the + internal ligament; and in being destitute of teeth. It resembles + Glycimeris, but is not incrassated. Fig. 68, Solenimya radiata. + + SOLENOCURTUS. Bl. (_Solen_ and _curtus_, short.) _Fam._ Pyloridea, Bl. + Solenacea, Lam.--_Descr._ Oval, elongated, equivalve, sub-equilateral, + with the edges nearly straight and parallel, and the extremities rather + truncated; umbones not very prominent, sub-central; hinge with or + without two or three rudimentary cardinal teeth; ligament prominent, + placed upon thick callosities; muscular impressions two, distant, + rounded; palleal impression straight, with a deep sinus. East + Indies--_Obs._ Distinguished from the true Solenes by the central + position of the umbones and an internal bar reaching partly across the + shell. + + SOLETELLINA. Bl. SANGUINOLARIA radiata. S. Diphos, f. 99. S. livida of + Sowerby, and similar species, are placed together in this genus. + + SPATHA. Lea. A sub-genus of IRIDINÆ, consisting of I. rubens and I. + nilotica, which have not distinctly crenulated margins. Spatha + solenoides, of Lea, is the genus Mycetopus D'Orbigny. Fig. 151. + + SPHÆNIA. Turt. A genus consisting of a small species resembling + Saxicava, in general appearance, but having a spoon-shaped process on + the hinge of one valve. S. Binghamii, Fig. 96. + + SPHÆROIDINA. D'Orb. A genus of microscopic Foraminifera. + + SPHÆRULACEA. Bl. The first family of Cellulacea consisting of the + following genera of microscopic Foraminifera: Miliola, Melonia, + Saracenaria, Textularia. + + SPHÆRULACEA. Lam. The fourth family of Cephalopoda, Lam. described as + multilocular, globular, sphærical, or oval, with the whorls enveloping + each other; some of them have a particular internal cavity, and are + composed of a series of elongated, straight and contiguous chambers + which altogether form a covering for the internal cavity. This family + contains the genera Miliola, Gyrogona and Melonia. + + SPHÆRULITES. Lam. (_Sphæra_, a sphere.) _Fam._ Rudistes, Lam. and + Bl.--_Descr._ Orbicular, inequivalve, irregularly foliated outside; + lower valve cup-shaped, depressed; upper valve nearly flat, like an + operculum.--_Obs._ These fossils are not regarded as shells by all + conchologists. S. foliacea, Fig. 193. + + SPHINCTERULUS. Montf. LENTICULINA, Bl. A genus of microscopic + Foraminifera. + + SPINES. (_Spina_, a thorn.) Thin, pointed spikes. + + SPINOSE. (Spinosus.) Having spines or elevated points, as Neritina + spinosa. Fig. 325. + + SPIRAL. (_Spira_, a spire.) Revolving outwards from a central apex or + nucleus, like the spring of a watch. A shell or an operculum, may be + spiral, without being produced into a pyramid. Bands of colour, striæ, + grooves, &c. commencing from the nucleus and following the volutions of + the shell, are described by the above word. + + SPIRAMILLA. Bl. A genus of Serpulacea, differing from other Serpulæ + principally in the characters of the animal. + + SPIRATELLA. Bl. LIMACINEA, Lam. Fig. 224. + + SPIRE. (_Spira._) The cone or pyramid produced in a non-symmetrical + univalve by its oblique revolution downwards from the apex or nucleus. + The spire, in descriptions, includes all the volutions above the + aperture. See Introduction. + + SPIRIFER. Sow. (_Spira_, a spire; _fero_, to bear.) _Order_, + Brachiopoda, Lam.--_Descr._ Transverse, equilateral; hinge linear, + straight, widely extended on both sides of the umbones, which are + separated by a flat area in the upper and larger valve; this area is + divided in the centre by a triangular pit for the passage of the + byssus; interior with two spirally convolute appendages.--_Obs._ This + genus, which is only known in a fossil state, is distinguished from + Terebratula externally, by the flat area in one valve, internally, by + the singular spiral process from which the above name is derived. Fig. + 214, 215. Most of the species belong to the mountain or carboniferous + limestone. + + SPIROGLYPHUS. Daud. A genus consisting of a species of Serpula _Auct._ + which makes a groove for itself in the surface of shells. Serpula + spirorbis, var. Dillwyn. Fig. 8. + + SPIROLINA. Lam. A genus of microscopic Foraminifera. + + SPIROLOCULINA. D'Orb. A genus of microscopic Foraminifera. + + SPIRORBIS. Lam. A genus composed of species of SERPULA, Auct. which are + coiled round in a spiral disc like a snake at rest. S. nautiloides, + fig. 5, is the common little white shell, found upon the shell of + lobsters. + + SPIRULA. (_Spira_, a winding compass.) _Fam._ Lituolata, Lam. Lituacea, + Bl.--_Descr._ Convolute, smooth, symmetrical, discoid, with parallel + unconnected whorls, divided into numerous chambers by transverse septa; + siphon continuous.--_Obs._ This pretty little shell is partly internal, + only a part of it being visible when on the animal. Fig. 471. + + SPISULA. Gray. A genus composed of MACTRA fragilis, and other similar + species, which have the ligament sub-external, marginal, not separate + from the cartilage; with the posterior lateral teeth double in one + valve, and single in the other. M. fragilis, fig. 80, is the species + figured for Spisula in Mr. Gray's paper on the Mactradæ, in the second + series of Loudon's Magazine of Natural History. We have since learned, + however, that it was figured there by mistake, not having been intended + for a Spisula, but belonging more properly to the genus Mactra, as + defined by Mr. Gray, whose description of Spisula, is as + follows:--"Shell ovate, trigonal, sub-angular at each end. Hinge and + lateral teeth as in Mactra, but hinge of left tooth small. Siphonal + inflexion ovate." The principal difference between Spisula and Mactra + is, that the ligament is not separated from the cartilage in the + former. + + SPONDYLUS. Auct. (_A shell-fish_, Ancients.) _Fam._ Pectenides, Lam. + Sub-ostracea, Bl.--_Descr._ Inequivalve, sub-equilateral, irregularly + foliaceous and spinose, auriculated, denticulated at the margins, + attached by the lower and deeper valve; hinge rectilinear, with two + prominent teeth in each valve, locking into corresponding cavities in + the opposite valve; umbones separated by a broad, elongated, triangular + disc in the lower valve; ligament contained in a groove, dividing the + triangular area in the centre; muscular impressions one in each valve, + sub-central, sub-orbicular. The Mediterranean, East and West Indies, + and China, produce Spondyli most abundantly.--_Obs._ This genus is + remarkable for the richness and beauty of the spines and foliations, + which adorn the external surface of most of the species, the splendid + colours by which many of them are varied, and the natural groupings + formed by their attachment to each other. Fig. 177, and Frontispiece. + + SPORULUS. Montf. A genus of microscopic Foraminifera. + + SQUAMOSE. (_Squama_, a scale.) Scaly, covered with scales, as the + pedicle of Pollicipes Mitellus, fig. 37*. + + STENOPUS. Guild. ([Greek: Stenos], narrow, [Greek: pous], foot.) A + genus nearly "allied to the Linnæan Helices, from all of which it + differs in the curious contraction of the pedal disc, and the caudal + tentaculum furnished with a gland beneath." The shell is described as + heliciform, umbilicated, transparent, with the aperture transverse. The + two species described are Stenopus cruentatus and lividus; they are + both from the Caribbæan Islands, Guild. Zool. Journ. xii. p. 528, tab. + 15, f. 1 to 5. + + STOMATELLA. Lam. See STOMATIA. + + STOMATIA. Auct. ([Greek: stoma], _stoma_, mouth.) _Fam._ Macrostomata, + Lam.--_Descr._ Sub-orbicular, oblong, auriform, variegated without, + iridescent within; spire depressed; aperture entire, very wide, + oblique; peritreme uninterrupted. _Obs._ This genus is known from + Haliotis by being destitute of the series of holes; is distinguished + from Sigaretus by the substance of the shell, the latter being + internal, and never pearly. Our description includes STOMATELLA, Lam. + The Stomatiæ are marine, and belong to the East Indies and New Holland. + Fig. 335, S. Phymotis. + + STORILLUS. Montf. 1, 131. A genus of microscopic Foraminifera, included + in the genus Rotalites in M. De Blainville's system. + + STRAPAROLLUS. Mont. A genus containing some species of HELIX, Auct. + Generic characters not defined. + + STREPTAXIS. Gray. _Fam._ Colimacea, Lam.--_Descr._ Ovate, or oblong; + when young, sub-hemispherical, deeply umbilicated, with rapidly + enlarging whorls. At length the penultimate whorl is bent towards the + right and dorsal side of the axis, and the umbilicus becomes depressed, + and often nearly closed. The mouth is lunulate, the edge slightly + thickened and reflected, and often with a single tooth on the outer + side of the inner lip.--_Obs._ This genus of land shells is separated + from Helix on account of the eccentricity of the penultimate whorl. S. + contusa, fig. 269. + + STRIATED. (_Stria_, a groove.) Marked with fine grooves or lines. + + STRIGOCEPHALUS. Defr. PENTAMERUS, Sow.? GYPIDIA, Dalman. + + STROMBUS. Auct. _Fam._ Alatæ, Lam. Angiostomata, Bl.--_Descr._ Oblong, + turrited, rather ventricose, solid; aperture generally lengthened, + terminating posteriorly in a short canal, and anteriorly in an + emargination or truncated canal; outer lip, when young, thin; when full + grown, thickened and expanded, lobed at the spiral extremity, sinuated + anteriorly near the caudal canal.--_Obs._ This well known genus + includes some species of immense size, commonly called conch shells. + Most of the recent species are brought from the Indian Ocean. Very few + fossil species are known. The young shells have very much the + appearance of cones, the outer lips being thin. There are also several + species which do not, even when full grown, thicken their outer lips + very considerably. The genus Strombus is distinguished from + Rostellaria, by the notch in the outer lip, which in the latter genus + is close to the canal. Fig. 406, S. pugilis. + + STROPHOMENA. Rafinesque. ORTHIS, Dalman. + + STROPHOSTOMA. Deshayes. A fossil shell, of the family of Colimacea, + Lam. in some degree resembling Anostoma, having the aperture turned + upwards towards the spire, it is, however, umbilicated, and is said to + have an operculum resembling that of Cyclostoma. It is the Ferussina of + Grateloup. Fig. 534, 5, 6. + + STRUTHIOLARIA. Auct. (_Struthio_, an Ostrich.) _Fam._ Canalifera, + Lam.--_Descr._ Oblong, turrited, thick; spire turrited, composed of + several angulated whorls; aperture oval, sub-quadrate, oblique; outer + lip thickened, reflected, advancing in the centre, receding towards the + extremities; inner lip thickened, expanded over the columella and part + of the body whorl.--_Obs._ This singular genus, consisting of three or + four recent species, is named "Pied D'Autruche" by the French, on + account of some resemblance in the outer lip to the foot of the + Ostrich. From New Zealand. Fig. 391, S. straminea. + + STYLIFER. Brod. (_Stylus_, a style; _fero_, to bear.)--_Descr._ Thin, + pellucid, turbinated; apex a little out of the perpendicular; aperture + wide anteriorly, gradually narrowing towards the spiral extremity, + where it terminates acutely.--_Obs._ This is a genus of small, + transparent shells, found burrowing in the rays of Starfish. There are + but two or three species at present known, one of which is elongated + like Terebra, the other nearly globular. Fig. 12, S. astericola. West + Indies, Gallapagos, and Britain. + + STYLINA. Flem. STYLIFER, Brod. + + SUB. (_under._) Used as a prefix and signifying nearly. Thus a + bivalve-shell, the valves of which are nearly alike, would be described + as _sub_-equivalve. + + SUB-APLYSIACEA. Bl. The first family of the order Monopleurobranchiata, + Bl. containing several genera of Mollusca without shells, and the genus + Pleurobranchus. + + SUB-BIVALVES. A term of distinction applied by De Blainville, to those + spiral univalves which have an operculum; these, as they constitute two + distinct pieces, he considers as forming a medium between univalves and + bivalves. + + SUB-MYTILACEA. Bl. The sixth family of the order Lamellibranchiata, Bl. + the shells belonging to which are described as free, rather pearly, + regular, equivalve; hinge dorsal, laminated; ligament external; two + muscular impressions; palleal impression not sinuated. This family, + with the exception of the last genus, agrees with the family Nayades of + Lamarck, and contains the genera Anodon, Unio, and Cardita. + + SUB-OSTRACEA. Bl. The second family of Lamellibranchiata, Bl. the + shells of which are described as of a compact texture, sub-symmetrical; + with the hinge rather complex; one single, sub-central, muscular + impression, without any traces of palleal impression. This family + corresponds with the Pectenides of Lamarck, and part of the genus + Ostrea in the system of Linnæus. It contains the genera Spondylus, + Plicatula, Hinnites, Pecten, Pedum, Lima. + + SUB-SPIRAL. Not sufficiently spiral to form a complete volution. + + SUBULA. Bl. (_An awl._) A generic name under which M. De Blainville + includes TEREBRA maculata, Auct. f. 428, together with nearly all the + species of Terebra, enumerated by Lamarck and other authors; only + leaving in the latter genus those species, which being more bulbous, or + ventricose, nearly resemble Buccinum in general form. These last + mentioned species, such as Terebra buccinoidea, (fig. 247) have been + formed into a new genus by Mr. Gray, under the name Bullia. If both + these genera were adopted, the genus Terebra would be extinct. + + SUBULATE. (_Subula_, an awl.) A term applied to shells which are long + and pointed as in Terebra. Fig. 427, 428. + + SUCCINEA. Drap. (_Succinum_, amber.) _Fam._ Colimacea, Lam. Limacinea, + Bl. _Sub-genus_, Cochlohydra, Fer.--_Descr._ Ovate, rather elongated; + aperture large, entire, longitudinal; spire short; outer lip thin, + continuous with the thin, sharp-edged columella; inner lip spread over + a part of the body-whorl.--_Obs._ The shells belonging to this genus of + partly amphibious mollusca, are distinguished from Limnæa by not having + a fold on the columella The S. amphibia is of a bright amber colour. + Fig. 265, 266. Temperate and tropical climates. + + SULCATED. (SULCATUS, lat.) Having grooves or furrows. + + SULCI. Grooves or furrows. + + SUTURE. (_Sutura_, lat.) A seam, stitch, joining together. Applied + particularly to the line which marks the joining of the whorls of the + spire. The suture is distinguished as _simple_, as in most cases; or + _double_, when accompanied by a parallel groove close to it; + _marginated_, when produced into a ledge by the matter which fills up + and covers it; _obsolete_, when it is filled up so as not to be + visible, as in the case of Ancillaria. + + SYLVICOLA. Humph. CYCLOSTOMA, Lam. + + SYMMETRICAL, ([Greek: sun], _syn_, similar; [Greek: metron], _metron_, + proportion.) Both sides alike. Although the term is used thus as one of + distinction, it is to be observed that no shells are strictly and + perfectly symmetrical; even in the Nautilus, the apex verges in a + slight degree towards one side of the shell. Two kinds of univalve are + symmetrical, or nearly so; 1st. Those which are symmetrically + convolute, as the Nautilacea and the Ammonacea, which are spiral; 2nd. + Those which are not spiral, but simply conical, as the patelliform + shells. Bivalves belonging to the Brachiopoda are also symmetrical. + _Ex._ Patella, fig. 229. Ammonites, fig. 478. + + SYMPHYNOTA. Lea. A genus of Nayades, in which Mr. Lea proposed to + include species of the genus UNIO, the valves of which are connate, or + united at the dorsal margin. We believe that this distinction, as a + genus, has been abandoned by its author. The fact is, that all the + Uniones are Symphynotæ when in a young state. In Unio Alatus, (fig. + 147) and Dipsas plicatus, (fig. 142) it will be observed that the + valves have not separated at the dorsal edge, but are broken lower + down. + + TAPADA. (Gray. Turton. p. 127.) A division of the genus HELIX, + containing HELIX aperta, Auct. or the Tapada snail. + + TAPES. Schum. PULLASTRA. Sow.? + + TECTUS. Montf. A genus composed of species of the genus Trochus, having + elevated, conical spires, and columella notched or truncated by a + spiral fold. Fig. 359. Trochus maculatus, presents an example. + + TELEBOIS. Montf. A genus of microscopic Foraminifera. + + TELESCOPIUM. Montf. CERITHIUM Telescopium, Auct. fig. 378. + + TELLINA. Linn. _Fam._ Nymphacea, Lam. Conchacea, Bl.--_Descr._ + Sub-equivalve, inequilateral, compressed, rounded anteriorly, slightly + beaked or angulated posteriorly, the posterior ventral margin having a + flexuosity; hinge with two cardinal and generally two lateral teeth in + each valve; muscular impressions, two in each valve, remote; palleal + impression with a large sinus.--_Obs._ The fold or bending in the + posterior margin distinguishes this genus from others which it nearly + resembles. It is composed of some bivalves of great beauty and variety, + which are found in nearly all climates. Fig. 105, T. radiata, 106, T. + lingua-felis. + + TELLINIDES. Lam. _Fam._ Nymphacea, Lam.--_Descr._ Sub-equivalve, + inequilateral, transverse, compressed, rounded anteriorly, slightly + beaked or angulated posteriorly; hinge with two cardinal teeth in each + valve, and one lateral tooth in one valve, very near the cardinal + teeth. Muscular impressions two, distant, palleal impression with a + large sinus. _Obs._ This genus is distinguished from Tellina in having + but one lateral tooth near the cardinal teeth. Fig. 107, T. rosea. + Tropical. + + TENUIPEDES. (_Tenuis_, slender; _pedes_, feet.) The second section of + the order Conchifera Dimyaria, divided into the families Mactracea, + Corbulacea, Lithophagidæ, Nymphacea. + + TERACLITA. Schum. CONIA, Auct. + + TEREBELLUM. Lam. (_Terebra_, an augur?) _Fam._ Convolutæ, Lam. + Angyostomata, Bl.--_Descr._ Smooth, slender, oblong, sub-cylindrical; + spire obtuse, short, sometimes hidden; (Seraphs, Montf.) aperture long, + narrow posteriorly, wider anteriorly; outer lip slightly thickened, + truncated, unconnected at the base with the columella; inner lip thin, + smooth, nearly straight, spread over a portion of the body-whorl, + continued in a ridge above the sutures of the spire.--_Obs._ Montfort + has separated the fossil species with hidden spires, under the name + Seraphs. (T. convolutum, Lam.) Only one recent species is known, of + which there are several varieties, one spotted, one marked in + sub-spiral lines, another in patches. It is brought from the East + Indies. Fig. 451, T. convolutum; 452, T. subulatum. + + TEREBRA. (_An augur, a piercer._) _Fam._ Purpurifera, Lam. + Entomostomata, Bl.--_Descr._ Subulate, elongated, pointed, turrited; + spire long, consisting of numerous whorls; aperture small terminating + in a short, reflected canal; outer lip thin; columella tortuous; + operculum horny. The recent species are mostly tropical.--_Obs._ Nearly + all the species enumerated by Lamarck and other authors are included by + De Blainville in his genus Subula; those few species which that + conchologist left in the present genus, being shorter and more + ventricose than the others, approximate in shape to some of the + Buccina, and are distinguished by Mr. Gray under the generic name + Bullia. It seems strange, that De Blainville, being convinced of the + necessity of separating the two groups, and consequently applying a new + generic term to one of them, should have given that term to the larger + number and the more typical species of the Lamarckian genus. Fig. 427, + Bullia vittata. (Terebra.) Fig. 428, Terebra maculata. (Subula.) + + TEREBRALIA. Sw. A genus of "Cerithinæ," Sw. thus described: "Outer lip + much dilated, generally uniting at its base to the inner lip; leaving a + round perforation at the base of the pillar; channel truncate; + operculum round: palustre. Mart. f. 1472." Sw. p. 315. + + TEREBRATING SHELLS. (_Terebro_, to pierce.) Shells which reside in + holes pierced in rocks, wood, &c. by means of some corrosive secretion + of the animal. _Ex._ Pholas, Teredo, &c. + + TEREBRATULA. Brug. (_Terebrans_, bored.) _Fam._ Brachiopoda, + Lam.--_Order._ Palliobranchiata, Bl.--_Descr._ Inequivalve, + equilateral, oval or sub-trigonal, ventricose or compressed, attached + by a tendon passing through an opening in the dorsal, or upper and + larger valve, the umbo of which advances beyond that of the other + valve; hinge destitute of a ligament, with two teeth in the dorsal + valve, locked into corresponding cavities in the ventral, or lower + valve, and with two curious processes originating at the umbo of the + lower valve, presenting, in some species, the appearance of fine + winding tape, advancing towards the front of the valve, and again + receding to the centre, where the ends unite; muscular impressions two, + placed near the centre of each valve.--_Obs._ The Terebratulæ are + included in the genus Anomia in the system of Linnæus. The recent + species are not very numerous--they are found in all climates. The + fossil species are more numerous than the recent ones, occurring in the + secondary and tertiary formations. T. Psittacea, fig. 202. + + TEREDINA. (From Teredo.) _Fam._ Tubicolæ, Lam. Adesmacea, Bl.--_Descr._ + Valves equal, inequilateral, with prominent umbones, as it were + soldered to the outside of the rounded end of a shelly tube, of which + they form a part; aperture of the tube partly divided; a flat accessary + valve placed on the umbones.--_Obs._ This genus, which is only known in + a fossil state, is distinguished from Teredo, by the valves being fixed + on the tube, and the tube being closed at one extremity. Fig. 46, 47, + T. personata. + + TEREDO. Auct. (_A piercer._) _Fam._ Tubicolæ, Lam. Adesmacea, + Bl.--_Descr._ Valves equal, inequilateral; presenting when closed, an + orbicular figure, with a large angular opening in front, and a rounded + opening at the back; placed at the anterior extremity of an irregular, + flexuous, elongated tube, open at both ends; the anterior termination + divided in a double aperture opened and closed at the will of the + animal by two opercula.--_Obs._ This genus of Molluscous Animals, is + remarkable for boring holes in wood, which are filled by their + elongated tubes, and give it a honey-comb appearance. Fig. 48. T. + Navalis. Fig. 49, a piece of bored wood. + + TERMINAL. When the umbones of a bivalve shell are placed at or near the + extremity, as in Mytilus, fig. 158, Pinna, fig. 162, they are said to + be _terminal_. The same term is also applied to the nucleus of an + operculum, when it forms an extreme point, or is close to one of the + edges. + + TESSELLATED. (Wrought in chequer-work). A term applied to the colouring + of shells, when arranged in regular defined patches like a tessellated + pavement. + + TESTACELLA. (_Testa_, a shell.) _Fam._ Limacinea, Lam. and + Bl.--_Descr._ Haliotoid, compressed; aperture wide, oblique; columella + flat, oblique; spire short, flat, consisting of less than two + whorls.--_Obs._ This shell which is extremely small compared with the + animal, is placed upon its back, near the posterior extremity. The + animal is found in some of our gardens, and very much resembles the + common garden slug. Fig. 261, T. Haliotoidea. + + TESTACEOUS. (_Testa_, a shell.) Shelly. Testaceous Mollusca, are soft + animals having shells. A testaceous operculum is one composed of shelly + matter. + + TETRACERA. Bl. The first family of the order Polybranchiata, Bl. + containing no genera of testaceous mollusca. + + TEXTILIA. Sw. A sub-genus of Conus, consisting of Conus bullatus, &c. + Sw. Malac. p. 312. + + TEXTULARIA. Defr. A genus of microscopic Foraminifera. + + THALAMUS. Montf. A genus described as resembling Conilites, but curved + and granulated. + + THALLEPUS. Sw. A genus of "Aplysianiæ," Sw. thus described: "Body more + slender and fusiform;" (than Aplysia,) "the lobes of the mantle short, + and incapable of being used for swimming; tentacula two, large, ear + shaped; eyes not visible. T. ornatus, _Sw._ Sp. Nov." Sw. p. 359. + + THALLICERA. Sw. A generic name under which Swainson distinguishes + AMPULLARIA Avellana, Auct. + + THECIDIUM. (_Thecas_, a box.) _Fam._ Brachiopoda, Lam. _Order_, + Palliobranchiata, Bl.--_Descr._ Lower valve concave, sub-trigonal, with + the umbo produced into a triangular, slightly incurved beak, and with + two short, pointed processes advancing from beneath the umbones; upper + valve flat, rounded square, with a short, blunt appendage, formed to + fit between the tooth-like process of the other valve; its inner + surface ornamented with symmetrically curved ridges. + + THECOSOMATA. Bl. The first family of the order Aporobranchiata, Bl. + containing the genera Hyalæa, Cleodora, Cymbulia, Pyrgo. + + THELICONUS. Sw. A sub-genus of Conus. Lardn. Cyclop. Malac. p. 312. + + THELIDOMUS. Sw. A generic name under which Swainson has described a + division of the genus Helix, and which he has also used to designate a + genus in the family of "Rotellinæ," founded upon an aggregate of loose + particles collected and agglutinated in a spiral form by the larva of + an insect. Sw. Malac. p. 330 and 353. + + THEMEON. Montf. A genus of microscopic Foraminifera. + + THEODOXUS. Montf. A division of the genus Nerita. Fig. 324, N. + virginea. + + THETIS. Sow. (_A sea nymph._) A genus of fossil shells, described as + resembling Mactra, but not having the internal ligament, and having + several small, acuminated, cardinal teeth, but no lateral teeth. It + resembles Tellina in some degree, but has not the posterior fold. + + THIARELLA. Sw. A sub-genus of Mitra, Lardn. Cyclop. Malac. p. 319. + + THRACIA. Leach. _Fam._ Lithophagidæ, Lam. Pyloridea, Bl. A genus + described as intermediate between Anatina, and Mya, and in some degree + resembling Corbula. T. corbuloides, fig. 93. + + THUNDER-STONES. One of the vulgar appellations which have been applied + to shells of the genus Belemnites. + + THIATYRA. Leach. A genus composed of AMPHIDESMA _flexuosa_, Lam. and + similar species, belonging more properly to the genus LUCINA. + + TIARA. Sw. A genus of "Mitranæ," Sw. thus described: "Aperture narrow, + linear, or of equal breadth throughout; outer lip and base of the body + whorl contracted, the former generally striated; an internal canal at + the upper part of the aperture; shell (typically) turrited, and equally + fusiform; representing the _Muricidæ_ and Cymbiola." Sw. Malac. p. 319. + The principal difference between Tiara and Mitra appears to be that in + the latter, the aperture is more linear and contracted in the centre. + Mitra Episcopalis is an example. + + TINOPORUS. Montf. A genus of microscopic Foraminifera. + + TIRANITES. Montf. A division of the genus Baculites. + + TOMELLA. Sw. A genus of "Pleurotominæ," Sw. thus described: "Fusiform, + smooth; the spire of very few whorls, and not longer than the channel; + inner lip with a thick callosity at the top; the slit short and wide; + lineata, En. Méth. 440, f. 2, clavicularis, Ib. f. 4. filosa. En. Méth. + 440, f. 6. lineolata. Ib. f. 11." Sw. p. 314. + + TOMOGERUS. Montf. ANASTOMA, Auct. Fig. 471. + + TONICHIA. Gray. Syn. B. M. p. 126. A genus composed of those species of + Chiton which have the margin smooth. + + TORNATELLA. Auct. _Fam._ Plicacea, Lam.--_Descr._ Oval, spirally + grooved; spire short, rather obtuse, consisting of few whorls; aperture + long, narrow, rounded anteriorly; outer lip simple; inner lip thin, + slightly spread, columella spiral, incrassated, confluent with the + outer lip. The recent species are few. Several fossil species occur in + London Clay, Inferior Oolite and Calcaire-grossièr. Monoptygma, Lea, + resembles this genus, but has a fold on the inner lip. Fig. 343, T. + solidula. + + TORTUOUS. (_Tortuosus_) Twisted. This adjective is sometimes applied as + a specific name; as Arca tortuosa. + + TRACHELIPODA. Lam. ([Greek: trachêlos], _trachelos_, a neck; [Greek: + poda], _poda_, foot.) The third order of the class Mollusca, in the + system of Lamarck. The trachelipodous mollusca are described as having + the posterior part of the body spirally twisted and separated from the + foot; always enveloped in a shell. The foot is free, flat, attached to + the base of the neck. Shell spiral, and enclosing the animal when at + rest. This order contains the families, Colimacea, Lymnacea, Melaniana, + Peristomiana, Neritacea, Janthinea, Macrostomata, Scalariana, Plicacea, + Canalifera, Alata, Purpurifera, Columellaria, Convolutæ. The genera + belonging to these families, are represented in the plates, fig. 264, + to 462. + + TRANSVERSE. (Crosswise.) A shell is said to be transverse, when its + width is greater than its length, that is, when it is longer from one + side to the other than from the umbones to the ventral margins. The + term is applied by some authors to express the direction of the lines + of growth in bivalve shells, and the spiral lines in spiral shells. See + CONCENTRIC. + + TRAPEZIUM. Meg. CYPRICARDIA, Lam. + + TRAPEZIFORM, or + + TRAPEZOID. ([Greek: trapezion], _trapezion_, _trapezium_; [Greek: + eidos], _eidos_, form.) Having four unequal and unparallel sides. _Ex._ + Cucullæa, fig. 133. + + TRIBULUS. Klein. RICINULA, Lam. + + TRICHOTROPIS. Brod. and Sow. ([Greek: Trichos], _trichos_, hair; + [Greek: tropis] _tropis_, keel.) _Fam._ Purpurifera, Lam.--_Descr._ + Turbinated, keeled, thin, umbilicated; aperture longer than the spire, + entire; columella obliquely truncated; outer lip thin, sharp; epidermis + horny, produced into long hairs at the angles of the shell; operculum + horny, with the nucleus lateral.--_Obs._ Although the shells of this + genus have something of the shape of Turbo, they are distinguished from + that genus at once by the thinness of the shell. They are also known + from Buccinum, by the absence of a canal. Only two or three species are + known, which belong to the Northern and Arctic Oceans. T. bicarinata, + fig. 429. + + TRIDACNA. Auct. _Fam._ Tridacnacea, Lam. Chamacea, Bl.--_Descr._ + Equivalve, regular, inequilateral, radiately ribbed, adorned on the + ribs with vaulted foliations, waved at the margins, with a large, + anterior hiatus close to the umbones, for the passage of a large + byssus, by which the animal fixes itself to marine substances; hinge + with a partly external ligament; two laminar teeth in one valve, one in + the other.--_Obs._ The beautiful shells composing this genus are of a + delicate white colour, tinged with buff. One species, the T. gigas, + attains a remarkable size, measuring from two to three feet across, and + weighing five hundred pounds. Tridacna is distinguished from Hippopus + by the large opening in the hinge. T. elongata, fig. 157. + + TRIDACNACEA. Lam. A family belonging to the first section of the order + Conchifera Dimyaria, Lam. described as regular, equivalve, solid, and + which are remarkable for the deeply sinuated or undulated ventral + margin. This family contains the genera: + + 1. HIPPOPUS. Valves closed at or near the hinge. Fig. 156. + + 2. TRIDACNA. An hiatus near the hinge. Fig. 157. + + TRIDENTATE. (_Tridentatus_.) Having three teeth, or salient points. + _Ex._ Hyalæa tridentata, fig. 226. + + TRIGONA. Schum.? Triangular species of CYTHEREA, such as C. lævigata, + Triplas corbicula, ventricosa, bicolor, &c. Fig. 117 _b._ + + TRIGONACEA. Lam. A family belonging to the order Conchifera Dimyaria, + containing the genera Trigonia and Castalia, the latter of which ought + to be removed to the Nayades. Fig. 139, 140. + + TRIGONAL. Triangular, having three sides. + + TRIGONELLA. Humph. MACTRA, Auct. + + TRIGONIA. Brug. ([Greek: trigônon], _trigonon_, triangular.) _Fam._ + Trigonata, Lam. Camacea, Bl.--_Descr._ Equivalve, inequilateral, + transverse, sub-trigonal, costated and granulated without, pearly and + iridescent within, denticulated on the inner margin, rounded + anteriorly, truncated posteriorly; hinge with four oblong, compressed, + diverging teeth in one valve, receiving between their grooved sides, + two similar teeth in the other; ligament external, thick; muscular + impressions two in each valve.--_Obs._ Only one recent species of this + marine genus is known, the T. pectinata, which comes from New Holland; + and was formerly so rare, that a much worn odd valve has been sold for + a considerable sum. It is of a brilliant pearly texture within, tinged + with purple or golden brown. Fossil species occur in Lias, upper and + lower Oolite, and Green-sand. T. Pectinata, fig. 139. + + TRIGONOSEMUS. König. A genus composed of species of TEREBRATULA, Auct. + which have one valve produced into a beak, perforated, or as it were + truncated at the apex. T. lyra, fig. 208, differing from Terebratula + lyra, Lam. + + TRIGONOSTOMA. A sub-genus of Helix, with a trigonal aperture. Gray's + Turton, p. 139. + + TRIGONOTRETA. König. A genus composed of species of Terebratula, Auct. + which have the hinge of the larger valve produced into a triangular + disc, divided by a triangular foramen in the centre. Spirifer, Sowerby, + belongs to this genus. Fig. 214, 215. + + TRILOBATE. ([Greek: Treis] three; [Greek: lobos], division, lobe.) + Divided into three lobes or principal parts. Ex. Malleus, Fig. 165. + + TRILOCULINA. D'Orbigny. A genus of microscopic Foraminifera. + + TRIPARTITE. (_Tripartitus_) composed of or divided into three separate + parts. + + TRIPHORA, or TRISTOMA. Deshayes. A genus composed of small reversed + species of CERITHIUM, Auct. which have the anterior canal closed at the + anterior of the aperture, but opened at the extremity, and a small + tubular opening on the upper part of the whorls, making three openings + on the body whorl. This genus stands in the same relation to Cerithium + as the Typhis to Murex. Fig. 375 in the old plates, and fig. in the new + plates. + + TRIPLEX. Humph. MUREX, Linn. + + TRIPLODON. Spix. HYRIA, Auct. + + TRIPTERA. Quoy et Gaimard, CUVIERA, Fer. Described in the Voyage de la + Coquille, and represented as a molluscous animal destitute of a shell. + + TRIQUETRA. Bl. Triangular species of VENUS Auct. + + TRISIS. Oken. ARCA tortuosa, Auct. + + TRISTOMA. Described as TRIPHORA. + + TRITON. Auct. _Fam._ Siphonostomata, Bl. Canalifera, Lam.--_Descr._ + Oblong or oval, thick, ribbed or tuberculated, with discontinuous + varices placed at irregular distances; spire prominent, mammillated; + aperture round or oval, terminating anteriorly in a generally long, + slightly raised canal; columellar lip granulated or denticulated; outer + lip thickened, reflected, generally denticulated within; epidermis + rough; operculum horny.--_Obs._ However nearly allied the Tritons may + appear to be to the Murices and Ranellæ there are still to be traced in + the shells of each of those genera, several constant and well marked + distinctions, by which they maybe at once recognized. In the Ranellæ, + the varices run in two rows along the spire; in the Murices, they form + three or more rows; but in the Tritons, they do not follow each other, + _i.e._ they do not occur in the same part of each volution. The large + species of Triton, are sometimes used as trumpets. The Tritons are + brought from the Mediterranean, Ceylon, the East and West Indies, and + South Seas. Fig. 398 to 401. + + TRITONIDEA. Sw. A genus of "Buccininæ," Sw. thus described: "Shell + bucciniform, but the basal half is narrowed, and the middle more or + less ventricose; spire and aperture equal. Pillar at the base with two + or three obtuse and very transverse plaits, not well defined; outer lip + internally crenated and with a superior siphon; inner lip wanting, or + rudimentary." This genus is the same as the one first distinguished by + Mr. Gray under the name of Pollia. We do not regret the discovery made + by Mr. Swainson of that name being previously occupied for a genus of + Lepidopterous Insects. Fig. 415, represents Tritonidea articularis. + (Pollia, Gray.) + + TRIVIA. Gray. A genus composed of those small species of CYPRÆA, Auct. + which are characterized by small ridges on the dorsal surface, and have + the anterior of the columella internally concave and ribbed. C. + Pediculus. Auct. fig. 449, 450. + + TROCHATELLA. Sw. A sub-genus of Helicinæ, consisting of those species + which are acute and trochiform. + + TROCHIA. Sw. A genus of the family Buccininæ, thus described: "shape + intermediate between Purpura and Buccinum; whorls separated by a deep + groove; inner lip when young, depressed, when adult, thickened, convex + and striated; basal canal very small. T. sulcatus. E. M. 422. f. 4." + Sw. Malac. p. 300. + + TROCHIDON. Sw. A sub-genus of "Trochinæ," Sw. Lardn. Cyclop. Malac. p. + 351. + + TROCHILÆA. Sw.? PILEOLUS, Auct. + + TROCHURUS. Humph. MONODONTA. Lam. + + TROCHUS. Auct. (_A top._) _Fam._ Turbinacea, Lam. Goniostomata, + Bl.--_Descr._ Turbinated, thick, striated, tuberculated or smooth; + spire elevated, conical, consisting of numerous whorls; under surface + discoid; aperture more or less depressed in an oblique direction, + generally angular; columella arcuated, more or less prominent at its + union with the outer lip, contiguous to the axis of the shell; + operculum horny, orbicular, with numerous whorls.--_Obs._ Lamarck + distinguished this genus from Turbo by the general form, which is more + conical, and the aperture, which is angulated, while that of Turbo is + rounded. Monodonta or Odontis is only separated on account of the notch + at the termination of the columella. But these characters glide so + imperceptibly from one genus to the other, that there is no line of + demarcation to be found but in the operculum. Accordingly, Sowerby (in + Gen. of Sh. 37.) has stated his reasons for considering as Trochi, all + the species which have horny opercula; and as Turbines, all those which + have testaceous opercula. Fig. 358 to 360. The Trochi are found in all + climates. + + TROPÆUM. Sow. CRIOCERATITES. + + TROPHON. Montf. MUREX Magellanicus, Auct. and several other species + which belong more properly to Fusus than to Murex. + + TRUMPET SHELL. A large species of Triton (variegatus), used by natives + of South Sea Islands as a trumpet, to call warriors and herds of cattle + together. It answers the purpose tolerably well, producing a very + sonorous blast. + + TRUNCATED. (_truncus_, cut short.) Terminating abruptly, as it were cut + short. _Ex._ Solenensis, fig. 60. + + TRUNCATULANA. D'Orb. A genus of microscopic Foraminifera. + + TRUNCATELLA. Risso. A genus composed of several species of land shells + which have been confounded by some authors with Cyclostoma. The genus + is thus described: "Shell turriculated, cylindrical, decollated or + truncated at the apex, no epidermis; aperture oval, short, with lips + continuous, simple." _Ex._ Truncatella truncatulina, Lowe, Zool. Journ. + t. 5. p. 80. Our plates, fig. 520, 521. It is found on the shores of + Britain, the Mediterranean, and West Indies. + + TUBA. Lea. A genus of small fossil shells, described as resembling + Turbo, but with the aperture more like that of Melania. Lea. Contrib. + Geol. + + TUBERCLE. (_tuberculus._) A small swelling excrescence, or knob. + + TUBERCULATED. Having a number of small lumps or pimples, as Turrilites, + fig. 483. + + TUBICINELLA. Lam. (_Tubicen_, a trumpeter.) _Order_, Sessile + Cirripedes, Lam.--_Descr._ A cylindrical tube, composed of six + elongated valves jointed together side by side, striated + longitudinally, surrounded by concentric rings; aperture circular, + enclosed by an operculum of four valves, placed perpendicularly in an + epiphragm.--_Obs._ The Tubicinellæ are found with nearly the whole + shell buried in the thick skin of the whale. T. Balænarum. + + TUBICOLARIA. Lam. (_Tuba_, a tube; _cola_, an inhabitant.) A family of + the order Conchifera Dimyaria, Lam. consisting of bivalves soldered as + it were within, or connected with, a testaceous tube. The genera + contained in this family may be thus distinguished. + + 1. ASPERGILLUM. Valves fixed, tube perforated and fringed. Fig. 44. + + 2. TEREDINA. Valves fixed, prominent, tube closed at one end. + Fossil. Fig. 46, 47. + + 3. CLAVAGELLA. One valve fixed, the other free. Fig. 45. + + 4. TEREDO. Both valves free, tube open at both ends. Fig. 48, 49. + + 5. FISTULANA. Valves free, tube closed at one end, straight, long. + Fig. 53, 54. + + 6. GASTROCHÆNA. Valves free, tube closed at one end, short, + bulbous. Fig. 52. + + TUBIVALVES. Bl. Shells composed of two valves connected in a tube, + corresponding with the family Tubicolæ of Lamarck. + + TULIPARIA. Sw. A sub-genus of "Coronaxis," Sw. Lardn. Cyclop. Malac. p. + 311. + + TURBINACEA. Bl. The sixth family of Polythalamacea, Bl. containing the + genera Cibicides and Rosallites, microscopic Foraminifera. + + TURBINACEA. Lam. A family of the first section of the order + Trachelipoda, Lam. containing the following genera. + + 1. SOLARIUM. With umbilicus reaching to the apex; including + _Bifrontia_ and _Orbis_. Fig. 353 to 356. + + 2. ROTELLA. A callosity on the under side. Fig. 357. + + 3. PHASIANELLA. Oval; operculum shelly. Fig. 367. + + 4. PLANAXIS. Columellar lip flat; aperture notched. Fig. 365. + + 5. TURBO. Top-shaped; mouth generally round; operculum shelly. Fig. + 368. + + 6. TROCHUS. Top-shaped; mouth generally angulated; operculum horny, + consisting of many whorls; including _Elenchus_. Fig. 358, 359, + 361. + + 7. MARGARITA. Operculum horny, consisting of few whorls; pearly. + Fig. 362. + + 8. LITTORINA. Similar, not pearly; including _Assiminnea_. Fig. + 363, 363*. + + 9. PHORUS. Attaching dead shells, stones, &c. Fig. 360. + + 10. MONODONTA or ODONTIS. A notch and prominent point at the lower + part of the aperture. Fig. 366. + + 11. LACUNA. With an umbilicus. Fig. 364. + + 12. TURRITELLA. Elongated, screw-shaped. Fig. 369 to 371. + + TURBINATED. (_Turbo_, a top,) Top-shaped. The term is applied generally + to those shells which are large at one extremity, and narrow to a point + at the other. _Ex._ Trochus, fig. 358; Turbinellus, fig. 382. + + TURBINELLUS. Auct. (_A little top._) _Fam._ Canalifera, Lam. + Siphonostomata, Bl.--_Descr._ Turbinated, thick, wide near the apex, + generally tuberculated; spire short, depressed, mammillated; aperture + rather narrow, terminating anteriorly in an open canal; outer lip + thickened within; columella having from three to five prominent, + compressed, transverse folds. The species of this genus are mostly + tropical.--_Obs._ The Turbinelli are a well marked genus of marine + shells, the species of which are numerous. No fossil species are known. + The genus Cancellaria makes the nearest approach to Turbinellus in some + characters, but may be distinguished by the roundness of its form, the + raised lines inside the outer lip, and the obliquity of the folds on + the columella. Fig. 382 to 384. + + TURBO. Auct. (_A top._) _Fam._ Cricostomata, Bl. Turbinacea, + Lam.--_Descr._ Turbinated, solid, ventricose, generally grooved or + tuberculated; spire short, pointed; aperture generally rounded, + sub-effuse anteriorly, entire; operculum shelly, solid, incrassated on + the outer side, horny and sub-spiral on the inner side. The Turbines + are mostly tropical.--_Obs._ The only certain means of distinguishing + this extensive genus of marine shells from Trochus, is the operculum, + which in the latter genus is horny, spiral, and composed of a great + number of whorls. The Trochi, however, are in general more conical, and + flatter at the under side of the whorls, and this constitutes Lamarck's + distinction between the genera. T. setosus, fig. 368. + + TURGID. (_Turgidus._) Puffed up, swollen, inflated. This term is + applied synonymously with Ventricose. + + TURRICULA. Humph. MELANIA, Auct. + + TURRICULACEA. Bl. The seventh family of the Order Polythalamacea, Bl. + containing the genus Turrilites, fig. 483. + + TURRILITES. Lam. (_Turris_, a tower; [Greek: lithos], a stone.) _Fam._ + Turriculacea, Lam. Ammonacea, Bl.--_Descr._ Chambered, turrited, + spiral; septa sinuous and lobate, perforated by a siphon; aperture + rounded, with the outer lip expanded. This genus, which is + distinguished from the other Ammonacea by having the spire produced, + _i. e._ not being convolute, consists of several species, occurring + only in chalk-marl. Fig. 483. + + TURRIS. Montf. A genus composed of those species of MITRA, Auct. which + have the whorls angulated, with the aperture lengthened and undulated. + + TURRITED. The spire of an univalve shell is said to be _turrited_ when + the whorls of which it is composed are regulated so as to have the + appearance of little turrets rising above each other, as in Mitra, fig. + 431. + + TURRITELLA. Lam. (_A little tower._) _Fam._ Turbinacea, Lam. + Cricostomata, Bl.--_Descr._ Turrited, elongated, generally grooved + spirally; spire pointed, consisting of numerous whorls; aperture + rounded or angulated; inner and outer lips thin, confluent anteriorly; + operculum horny.--_Obs._ The shells composing this well defined genus, + are commonly called screws, a name to which the spiral grooves of most + of the species seems to entitle them. Fig. 370, T. imbricata. + + TYMPANOSTOMA. Schum. (_Timbrel mouth._) POTAMIS, Brongn. + + TYPHIS. Montf. A genus composed of MUREX tubifer, Auct. and other + similar species, which have the canal closed and a perforated tube + between each varix on the angulated part of the whorls. Besides the + fossil species originally described, there are now five species known, + which are figured in part 200, of the Conchological Illustrations by + the Author. Typhis tubifer, fig. 397. + + ULTIMUS. Montf. (_The last._) A genus composed of OVULUM gibbosum, + Auct. fig. 443, and other species in which the canals are not + distinctly defined, nor elongated. This fanciful name is given to the + genus on account of its being described in the last page of the book. + + UMBILICATED. (_Umbilicatus._) Having an umbilicus, as Nautilus + umbilicatus. + + UMBILICUS. (_A navel._) The hollow formed in spiral shells when the + inner side of the volutions do not join each other, so that the axis is + hollow. The umbilicus is marked with the letter u in Helix algira, fig. + 279. The term is also used to express any small, neat, rounded hollow. + + UMBO. (_The boss of a buckler or shield._) The point of a bivalve shell + above the hinge, which constitutes the apex or nucleus of each valve, + from which the longitudinal rays diverge, and the lines of growth, + commencing at the minutest circle, descend in gradually enlarging + concentric layers to the outer margin. The umbones will be marked with + the letter _u_, in Cytherea, fig. 117. + + UMBRELLA. (_A little shade._) _Fam._ Semiphyllidiana, Lam. Patelloidea, + Bl.--_Descr._ Patelliform, sub-orbicular, compressed, rather irregular; + apex slightly raised, placed near the centre; margin acute; internal + surface with a central, callous, coloured disc, surrounded by a + continuous, irregular muscular impression.--_Obs._ This genus is known + from Patella, by its continuous muscular impression. It is commonly + called the Chinese Umbrella shell. There are but two species at present + known; the U. Mediterranea, and the U. Indica, fig. 233. + + UNDATED. (_Unda_, a wave.) Waved. + + UNDULATED. (_Undulatus._) Minutely waved. + + UNGUICULATED. (_Unguis_, a nail or hoof.) An unguiculated operculum is + one in which the layers are disposed laterally, and the nucleus + constitutes part of the outer edge. + + UNGULINA. Daud. (_Ungula_, a nail or claw.) _Fam._ Mactracea, Lam. + Conchacea, Bl.--_Descr._ Equivalve, sub-orbicular, sub-equilateral, + with margins entire, simple, closed all round; hinge with one short, + sub-divided cardinal tooth in each valve, and a very minute additional + tooth in one valve, an oblong ligamentary pit divided into two + portions, one of which receives the cartilage, the external ligament is + immediately below the umbones; muscular impressions, two in each valve, + oblong; impression of the mantle entire. U. transversa, fig. 88. Coast + of Africa. + + UNI-AURICULATED. Having one AURICLE. See AURICULATED. + + UNICORNUS. Montf. MONOCEROS, Auct. + + UNIO. (_A pearl._) _Fam._ Nayades, Lam. Submytilacea, Bl.--_Descr._ + Inequilateral, equivalve, regular, free, pearly within, covered by a + smooth epidermis without; umbones prominent, generally corroded; + muscular impressions two in each valve, lateral, distant; the anterior + composed of several small divisions; hinge varying in age, species, and + individuals.--_Obs._ The above description is framed so as to include + all the genera of the Lamarckian Nayades, together with Castalia, which + are placed in the family Trigonacea, they are all fresh-water shells, + commonly called fresh-water muscles. The distinctions of the various + genera into which they have been divided, will be found in their + respective places, and under the name Nayades. They are all represented + in figures 140 to 152. Of these fig. 145 to 148, are more generally + considered as forming the genus Unio. + + UNIOPSIS. Sw. A sub-genus of Alasmodon. Sw. p. 382. + + UNIVALVE. (_Unus_, one; _valva_, valve.) A shell consisting of a single + piece, as distinguished from Bivalves and Multivalves, which are + composed of two or more principal pieces. Spiral shells having an + operculum, are called sub-bivalves by some authors. + + UPPER-VALVE. The free valve in attached bivalves. + + UVIGERINA. D'Orb. A genus of microscopic Foraminifera. + + VAGINA. Megerle. SOLEN _vagina_, Auct. + + VAGINULA. (_A little sheath, the husk of corn._) _Class_, Pteropoda, + Lam.--_Descr._ Pyramidal, slightly inflated in the centre, thin, + fragile; aperture oblong, with the edges turned slightly + outwards.--_Obs._ The little shells of this genus, which are only known + in a fossil state, differ from Cuvieria in being pointed at the + extremity. Found in the tertiary beds of Bordeaux. V. Daudinii, fig. + 225. + + VAGINULINA. D'Orb. A genus of microscopic Foraminifera. + + VALVATA. Müll. _Fam._ Peristomata, Lam. Cricostomata, Bl.--_Descr._ + Thin, turbinated; spire short, composed of from three to six rounded + whorls; aperture circular; peritreme acute, entire; operculum horny, + spiral.--_Obs._ This genus of small shells resembles Cyclostoma, from + which the recent species may be known by the horny texture of the + external surface, being fresh-water shells. The fossils of course + belong to the fresh-water formations. V. piscinalis, fig. 322. Europe + and North America. + + VALVES. (_Valva_, a door, a folding piece.) The two pieces composing a + bivalve shell, which close upon each other, turning upon a hinge + consisting of a ligament, cartilage, and teeth. See BIVALVE, + MULTIVALVE, and UNIVALVE. + + VALVULINA. D'Orb. A genus of microscopic Foraminifera. + + VARIX. (_A swelling vein._) A varix is formed on the outer surface of a + spiral shell, by the thickened, reflected edge of a former aperture, + after fresh deposits of testaceous matter have increased the size by + adding to the growth of the shell beyond it. In this manner there are + frequently many varices, or edges of former apertures, in various parts + of the spire and the body whorl. They are sometimes placed at regular + distances from each other, as in Harpa, fig. 419; sometimes + _continuous_, as in Ranella, fig. 394; sometimes _discontinuous_, as in + Triton, fig. 398; sometimes _ramose_, as in Murex, fig. 395; sometimes + _simple_, as in Scalaria, fig. 351; sometimes _spinose_, as in Murex + spinosus. The term _varix_ has also been applied to any swelling ridge, + such as that on the lower part of the columella of Ancillaria, fig. + 456. + + VELATES. Montf. NERITINA perversa, Auct. Fig. 326. + + VELLETIA. Gray? A genus described as differing from ANCYLUS in being + dextral. VELLETIA lacustris, ANCYLUS lacustris, Auct. fig. Sowerby Gen. + fig. 2. + + VELUTINA. Auct. _Fam._ Macrostomata, Lam.--_Descr._ Sub-globose, + covered with a velvety epidermis; spire short, composed of two rapidly + enlarged ventricose whorls; aperture large, sub-ovate; peritreme thin, + entire, separated from the last whorl; columella tortuous, + thin.--_Obs._ This shell does not resemble any other genus in the + family. Fig. 337. Northern Seas. + + VENERICARDIA. Lam. A genus composed of the shorter species of Cardita. + + VENERIRUPIS. Lam. (From _Venus_ and _rupis_, a rock.) The oblong + species of Venus Auct. which live in cavities of rocks and stones. This + genus is united by Sowerby with some other species of Venus under the + name Pullastra. V. Vulgaris, fig. 97. + + VENTRAL. (_Venter_, the belly.) The margin of a bivalve shell opposite + the hinge. The under valve in Brachiopodous bivalves is the ventral + valve. The ventral surface of an univalve spiral shell is that which + faces the observer when the aperture is placed towards him. The ventral + part of the whorls of symmetrical convolute shells, is the inner part, + that which is nearest to the spire. + + VENTRAL SIPHON. In symmetrical convolute univalves, is one placed near + the inner edge of the whorls. + + VENTRICOSE. (_Ventricosus._) Swelled, rounded out, (_bombé Fr._) as + Harpa ventricosa, fig. 419. + + VENUS. Auct. (_Goddess of Beauty._) _Fam._ Marine Conchacea, Lam. + Conchacea, Bl.--_Descr._ Equivalve, inequilateral, sub-globose, + sub-ovate, transverse, externally rugose, striated, ribbed, cancellated + or smooth; margins entire, simple, close; hinge with three more or less + distinct cardinal teeth, diverging from the umbones in each valve; + muscular impressions two, lateral, distant; palleal impressions + sinuated posteriorly; ligament external.--_Obs._ This extensive genus, + including some bivalves of splendour and beauty, justifying the name + given to it, may be known from Cytherea by the absence of a lateral + tooth, which is found near the cardinal teeth in the latter. Artemis is + distinguished not only by its beautiful form, but by the deep angular + sinus in the palleal impression. Fig. 119, 119 a. Found mostly in + temperate and tropical climates. + + VERMETUS. Adanson. _Fam._ Scalariana, Lam. Cricostomata, Bl.--_Descr._ + Spiral at the apex, irregularly twisted towards the aperture; aperture + round, small.--_Obs._ This shell resembles the Serpulæ in general + appearance, although it is regularly spiral near the apex. The animal + is known to be a true mollusc, rather nearly allied to that of the + genus Dentalium, which is also placed wrongly in the Lamarckian system. + Vermetus Lumbricalis, fig. 345. Coast of Africa. + + VERMICULAR. (_Vermicularis._) Worm-shaped, tubular, serpentine. _Ex._ + Vermilia triquetra, fig. 7. + + VERMICULARIA. Lam. VERMETUS, Adanson; afterwards VERMETUS, Lam. + + VERMILIA. Lam. A genus composed of species of Serpula, which are + attached by the whole length of the shell, no part being free. Vermilia + triquetra, fig. 7. + + VERTEBRALINA. D'Orb. A genus of microscopic Foraminifera. + + VERTEX. Apex. + + VERTIGO. Müll. _Fam._ Colimacea, Lam.--_Descr._ Cylindrically fusiform, + sinistral, hyaline; aperture marginated, sinuated, denticulated on the + inner edge; peristome sub-reflected.--_Obs._ This genus of minute land + shells, resembles Pupa, but is a reversed, hyaline shell. Vertigo + pusilla, fig. 293. Europe. + + VERRUCA. Schum. CLITIA, Leach. + + VESICA. Sw. A sub-genus of Bulinus, Sw. p. 360. + + VEXILLA. Sw. A genus of "Nassinæ," Sw. thus described: "General shape + of _Purpura_, the inner lip flattened and depressed; the outer, when + adult, thickened, inflected and toothed; aperture wide; picta _Sw._ + Chem. pl. 157, f. 1504-5." Sw. Malac. p. 300. + + VIRGULINA. D'Orb. A genus of microscopic Foraminifera. + + VITRELLA. Sw. A sub-genus of "Bullinæ," Sw. Lardn. Cyclop. Malac. p. + 360. + + VITRINA. Drap. (_Vitreus_, glassy.) _Fam._ Limacinea, Lam. and + Bl.--_Descr._ Ovate, thin, glassy, fragile; spire short; last whorl + large; aperture wide, transverse; peritreme simple; columella spiral, + linear.--_Obs._ This genus of land-shells is not known in a fossil + state. The recent species are found among moss and grass, in shady + situations. De Ferussac has divided this genus into Helicolimax, fig. + 263, and Helixarion, fig. 262. + + VITULARIA. Sw. A genus of "Muricinæ," Sw. thus described: "General + habit of _Muricidea_, but the inner lip is depressed and flattened as + in the _Purpurinæ_; varices simple, nearly obsolete. Tuberculata, Sw. + En. M. 419. fig. 1. (_Murex vitulinus_, Auct.)" Sw. p. 297. + + VIVIPARA. A generic name given by Montfort, and retained by some + authors for PALUDINA, Lam. on account of the animals being + _viviparous_, i. e. the young being perfectly formed before they leave + the ovaries. + + VIVIPAROUS. See VIVIPARA. + + VOLUTA. Auct. (_Volvo_, to revolve.) _Fam._ Columellaria, Lam. + Angyostomata, Bl.--_Descr._ Sub-ovate, rather angulated, thick, + generally tuberculated, smooth; spire short, conical, with a + mammillated apex; aperture generally angulated, large, terminating + anteriorly in a deep notch; columella smooth, with several plaits, of + which the lowest is the largest; outer lip thickened within.--_Obs._ + The genus Voluta, as left by Linnæus, is only characterized by the + folds on the columella, and includes many shells which, although they + agree in this respect with the genus, are yet quite opposite to each + other in all other characters. Thus the Auriculæ, which are land + shells, and have the aperture entire, are mixed up with others which + are marine, and have a canal, as Turbinellæ, and the Fasciolariæ, and + others which have merely a notch, as the true Volutes. This genus, as + it is circumscribed at present, includes a great number of beautiful + shells, most of which are rich in colouring. CYMBA and MELO have been + separated by Mr. Broderip from the genus VOLUTA of Lamarck, for reasons + stated in their respective descriptions. Fig. 443. + + VOLVARIA. Lam. (_Volva_, a shuttle.) _Fam._ Columellaria, + Lam.--_Descr._ Cylindrical, convolute, spirally striated; spire very + short, nearly hidden; aperture narrow, as long as the whole shell; + columella with three oblique plaits; outer lip dentated.--_Obs._ The + Volvaria are only known in a fossil state, and resemble some species of + Bulla in general form, but are distinguished by the plaits on the + columella. Fig. 439, V. concinna. + + VOLUTELLA. Sw. (_A little volute._) A genus composed of those species + of MARGINELLA, Auct. which have the spire concealed, and the aperture + smooth within. Fig. 438, PERSICULA of Schumacher. + + VOLUTILITHES. Sw. (_Voluta_, and [Greek: lithos], _lithos_, a stone.) A + genus composed of some fossil species of Voluta, which have the plaits + on the pillar generally numerous, indistinct, and sometimes wanting + altogether, with a pointed spire. Fig. 436, V. spinosa. + + VOLUTION. See WHORL. + + VORTICIALIS. Lam. A genus of microscopic Foraminifera. + + VULSELLA. Lam. (_A little tongue._) _Fam._ Ostracea, Lau. Margaritacea, + Bl.--_Descr._ Equivalve, irregular, longitudinal, compressed, oblong; + umbones separated by a slight area in both valves; hinge with a large + pit in the centre, containing the cartilage, the ligament being spread + over the areas; muscular impressions, one on each valve, sub-central, + oblong.--_Obs._ This genus differs from Ostræa in the equality of the + valves, and in having a hollow pit in the hinge for the cartilage. + Vulsella lingulata, fig. 185. + + WATERING-POT. Aspergillum, fig. 44, commonly so called on account of + the resemblance of its perforated termination to that of the spout of a + watering-pot. + + WENTLE TRAP. Scalaria pretiosa, commonly so called. + + WHORL. A complete turn or revolution round the imaginary axis of a + spiral shell. The last whorl is called the _body-whorl_. The whorls are + described as _non-contiguous_, when they do not touch each other; + _continuous_, in the opposite case. _Depressed_ when they are flat. + They are _angulated_, _heeled_, or coronated; _distinct_, or + indistinct. They are sometimes, as in Cypræa, hidden by the last whorl. + + XYLOPHAGA. Sow. ([Greek: xulon], _zylon_, wood; [Greek: phagô], + _phago_, to eat.) _Fam._ Tubiscolæ, Lam.--_Descr._ Equivalve, globose, + closed at the back; with a large, angular hiatus in front; hinge with a + small curved tooth advancing from beneath the umbones in each + valve.--_Obs._ This shell, which is found in a cylindrical cavity, + eaten in wood by the animal, resembles Teredo, but has not the shelly + tube, nor the posterior hiatus. X. dorsalis, fig. 50, 51. + + XYLOTRYA. Leach. XYLOPHAGA, Sow. + + ZONITES. Montf. A genus formed of Helix Algira, and other similar + species with depressed spires and large umbilici; included in the + sub-genus Helicella. Fig. 279. + + ZUA. Leach. A genus described as differing from Bulinus in having a + polished epidermis, and a thickened, not reflected lip. Zua lubrica, B. + lubricus, Auct. + + ZURAMA. Leach. A sub-genus of Helix. H. pulchella, Auct. Gray's Turton, + p. 41. + + * * * * * + + +EXPLANATION OF PLATES, + +AND SYSTEMATIC VIEW OF THE + +LAMARCKIAN ARRANGEMENT. + + _Class_, ANNELIDES. + _Order_, SEDENTARIA. + _Fam._ Dorsalia. + + FIG. + + 1. Siliquaria anguina. Agathirses, Montf. + + _Fam._ Maldania. + + 2. Dentalium octogonum. + + 3. Pharetrium fragile, with the outer tube broken. + + _Fam._ Serpulacea. + + 4. Serpula bicarinata. + + 5. Spirorbis Nautiloides, on sea-weed. + + 6. Galeolaria decumbens, on a Conia. + + 7. Vermilia triquetra. + + 8. Spiroglyphus, on a portion of Patella. + + 9. Magilus antiquus, old shell. Campulotus, Guild. (from Guerin.) + + 10. The same, in a young state. + + 11. Leptoconchus striatus. + + 12. Stylifer astericola. + + 13. The same, in a portion of Star-fish. + + _Class_, CIRRIPEDES. + _Order_, SESSILE CIRRIPEDES + + 14. Tubicinella Balænarum. + + 15. Coronula Testudinaria. Chelonobia, Leach, Astrolepas, Klein. + + 16. ---- Balænaris. Cetopirus, Ranz. + + 17. ---- diadema. Diadema, Ranz. + + 18. Chthalamus, Ranz. (from Blainville.) + + 19. Platylepas pulchra, Leach. One valve separate, showing the inside. + + 20. Clitia Verruca, Leach. Octhosia, Ranz. Verruca, Schum. + + 21. Conia porosa. Teraclita, Schum. + + 22. Elminius Leachii. + + 23. Catophragmus imbricatus, (from Sowerby's Genera.) + + 24. Octomeris angulosus, (from Sow. Gen.) + + 25. Balanus tintinnabulum. + + 26. ---- Montagui. Acasta, Leach. + + 27. ---- galeatus, Conoplæa, Say. + + 28. Creusia gregaria. _b._ showing the internal structure. + + 29. Nobia grandis. + + 30. Savignium crenatum. } + } + 31. Pyrgoma cancellata. } Pyrgoma, Auct. + } + 32. Adna Anglicum. } + } + 33. Megatrema semicostata.} + + _Order_, PEDUNCULATED CIRRIPEDES. + + 34. Pentelasmis lævis. Antifa, Lam. a. anterior. + + 35. Scalpellum vulgare. + + 36. Smilium Peronii. + + 37. Pollicipes polymeus. Ramphidoma, Schum. + + 37*. Pollicipes mitellus. Capitulum, Klein. + + 38. Brismæus Rhophodius. + + 39. Lithotrya dorsalis. Absia, Leach, Litholepas, Bl. + + 40. Ibla Cuvieriana. + + 41. Heptalasmis Warwickii. Octolasmis, Gray. + + 42. Cineras vittatus. + + 43. Otion Cuvieri. + + _Class_, CONCHIFERA. + _Order_, C. DIMYARIA. + _Fam._ Tubicolaria. + + 44. Aspergillum vaginiferum. Penicillus, Brug. + + 45. Clavagella, a fossil species. + + 46. Teredina personata. + + 47. Lignite, pierced by Teredinæ. + + 48. Teredo navalis; _a_, tube (from Sowerby's Genera.) + + 49. Wood bored by Teredo. + + 50. Xylophaga dorsalis. Xylotrya, Leach. + + 51. The same, in wood. + (This would be more properly placed in Pholadaria.) + + 52. Gastrochæna Modiolina, in the tube (from Sowerby's Genera.) + + 53. Fistulana Clava. } + } (From Sowerby's Genera.) + 54. Tube of the same. } + + _Fam._ Pholadaria. + + 55. Pholas Dactylus; _a_, plates of the hinge. + + 56. ---- papyracea. Pholadidæa. + + 57. Pholadomya Candida. + + 58. Galeomma Turtoni. + + 59. Front view of the same. + + (Here Xylophaga should be placed, see Tubicolaria.) + + _Fam._ Solenacea. + + 60. Solen ensis. Ensis, Schum. Ensatella, Sw. + + 61. Solen radiatus. Solenocurtus, Bl. Leguminaria, Schum. Siliqua, + Megerle. + + 62. Lepton squamosum. (from Turton.) + + 63. Novaculina gangetica. + + 64. Glanconome Chinensis. + + 65. Panopæa Australis. } + } (From Sowerby's Genera.) + 66. Hinge of Panopæa Faujasii.} + + 67. Glycimeris Siliqua. + + 68. Solenimya Mediterranea. + + _Fam._ Myaria. + + 69. Anatina rostrata. Auriscalpium, Megerle. + + 70. Anatinella Sibbaldii. + + 71. Mya truncata. + + 72. Periploma inæquivalvis. Osteodesma, Desh. _a_, bone of the + hinge, (from Blainville.) + + 73. Myochama anomioides; lower valve with clavicle, and hinge of + upper valve. + + 74. External view of the same, attached to a Trigonia. + + 75. Cleidothærus Chamoides, attached valve. + + 76. Upper valve of the same, with the clavicle. + + _Fam._ Mactracea. + + 77. Lutraria papyracea. Ligula, Leach. Carinella, Adans. + + 78. ---- Solenoides. Cutellus ----? + + 79. Mactra Stultorum. + + 80. ---- plicataria. Spisula? Gray. + + 81. ---- Spengleri. Schizodesma, Gray. + + 82. ---- bicolor. Mulinia, Gray. + + 83. Gnathodon cuneatus. Clathodon, Conrad. + + 84. Crassatella rostrata. + + 85. Amphidesma reticulatum. + + 86. Erycina plebeja. Mesodesma, Desh. + + 87. Cuming mutica. + + 88. Ungulina transversa, (from Sowerby's genera.) + + _Fam._ Corbulacea. + + 89. Corbula nucleus. + + 90. Pandora rostrata. + + _Fam._ Lithophagidæ. + + 91. Petricola Roccellaria. + + 92. ---- Carditoidea. Coralliophaga, Bl. + + 93. Thracia corbuloides. + + 94. Saxicava rugosa. + + 95. Hiatella biaperta. + + 96. Sphænia Binghamii. + + 97. Venerirupis vulgaris. + + _Fam._ Nymphacea. + + 98. Sanguinolaria rosea. Lobaria, Schum. + + 99. ---- Diphos. Soletellina, Bl. + + 100. Psammobia Ferroensis. Gari, Schum. + + 101. Corbis fimbriata. Fimbria, Megerle. + + 102. Grateloupia Moulinsii. (from Lea.) + + 103. Egeria triangulata, (from Lea.) + + 104. Lucina tigerina. + + 105. Tellina radiata. + + 106. ---- lingua-felis; _a_, showing the fold in the ventral + margin. + + 107. Tellinides rosea. + + 108. Donax cuneatus. + + 109. Capsa Braziliensis, young. + + 110. Astarte Danmoniensis. Crassina, Lam. + + Fluviatile Conchacea. + + 111. Cyclas rivicola. Cornea, Megerle. + + 112. Pisidium amnicum. Pisum, Megerle. + + 113. Cyrena fuscata. Corbicula, Megerle. + + 114. Cyrenoides Dupontia. + + 115. Potamophila radiata. Galathæa, Lam. _v._ ventral margin. + + Marine Conchacea. + + 116. Cyprina vulgaris. Arctica, Schum. + + 117. Cythera Meretrix; _e._ escutcheon. + + 117 _a._ C. Meroe; _Gen._ Meroe. + + 117 _b._ C. Tripla; _Gen._ Trigona. + + 117 _c._ C. maculata; _Gen._ Chione. + + 117 _d._ C. Castrensis; _Gen._ Circe. + + 118. Artemis lincta; _s_, sinus in the Palleal impression. + + 119. Venus cancellata. Antigona, Schum. _a._ anterior; _p._ + posterior; _c._ cardinal teeth. + + 119 _a._ V. Verrucosa. Dosina, Schum. + + 120. Pullastra Textile. + + _Fam._ Cardiacea. + + 121. Venericardia, recent species, resembling V. planicostata, Lam. + + 122. Cardium Dionæum. Cardissa, Sw. Hemicardium, Nonnull. + + 123. ---- angulatum. + + 123*. ---- Greenlandicum. Aphrodita, Lea, Acardo, Sw. + + 123**. --- hemicardium. _Gen._ Hemicardum. + + 124. Cardita calyculata. + + 125. Cypricardia angulata. + + 126. Isocardia Moltkiana. + + 127. Megalodon cucullatus, (from Sow. Min. Con.) + + 128. Hippagus Isocardioides, (from Lea.) + + 129. Hippopodium ponderosum, (from Sow. Min. Con.) + + 130. Pachymya gigas, (from Sow. Min. Con.) + + _Fam._ Arcacea. + + 131. Arca antiquata. + + 132. Bysso-arca Noæ. + + 133. Cucullæa auriculifera, (from Sowerby's Genera.) + + 134. Pectunculus pilosus. + + 135. Myopara costata, (from Lea.) + + 136. Crenella. + + 137. Nucula margaritacea, three views. + + 138. Solenella Norrissii. + + _Fam._ Trigonacea. + + 139. Trigonia pectinata. + + 140. Castalia ambigua. Tetraplodon pectinatus, Spix. + + _Fam._ Nayades. + + 141. Alasmodon complanatus, Say. Margaritana, Schum. + + 142. Dipsas plicatus, Leach. Cristaria, Schum. + + 143. Hyria corrugata, Lam. Paxyodon, Schum. Triplodon. + + 144. Syrmatophora, Sow. Prisodon, Schum. Diplodon, Spix. + + 145. Unio littoralis, Lam. Mysca ovata, Turton. + + 147. ---- Alatus. Symphynota, Lea. + + 148. ---- Atratus, Lam. Naia, Sw. + + 149. Monocondylæa Paraguayana. + + 150. Iridina elongata. Pleiodon, Conrad. } Platiris, Lea. + } + 151. Mycetopus solenoides, D'Orb. Spatha, Lea. } + + 152. Anodon Cataractus. + + _Fam._ Chamacea. + + 153. Chama Lazarus. Jataronus, Adanson. + + 154. Diceras perversum, (from Sowerby's Genera.) + + 155. Etheria semilunata. + + _Order_, MONOMYARIA. + _Fam._ Tridacnacea. + + 156. Hippopus maculatus. + + 157. Tridacna elongata. + + _Fam._ Mytilacea. + + 158. Mytilus achatinus. + + 159. ---- polymorphus. Dreissina. + + 160. Modiola Tulipa. + + 161. Lithodomus Dactylus. + + 162. Pinna saccata. + + _Fam._ Malleacea. + + 163. Avicula Hirundo. + + 164. ---- margaritifera. Meleagrina, Lam. + + 165. Malleus Vulgaris. Himantopoda, Schum. + + 166. Perna Ephippium. + + 167. Catillus Lamarckii. Inoceramus, Sow. (from Blainville.) + + 168. Crenatula mytoloides. } + } + 169. Gervillia aviculoides. } (from Sowerby's Genera.) + } + 170. Pulvinites Adansonii. } + + _Fam._ Pectinides. + + 171. Pecten varius. Janera, Schum. + + 172. ---- Plica. Decadopecten, Rüppell. + + 173. Hinnites Pusio. Pecten Pusio, Lam. + + 174. Lima squamosa. + + 175. Dianchora striata, (from Sow. Min. Con.) + + 176. Plagiostoma spinosum, (from Sow. Min. Con.) + + 177. Spondylus Americanus, hinge. (See Frontispiece.) + + 178. Plicatula gibbosa. Harpax, Parkinson. + + 179. Pedum Spondyloideum, (from Sow. Gen.) + + _Fam._ Ostracea. + + 180. Ostrea edulis. + + 181. ---- Folium. Dendostrea, Sw. + + 182. Gryphæa incurva. + + 183. Exogyra conica, (from Sow. Min. Con.) + + 184. Placuna placenta. _Gen._ Placenta, Schum. + + 185. Vulsella lingulata. + + 186. Anomia Ephippium. + + 187. Hinge of the same, with bony process. + + 188. Hinge, showing the fissure. + + 189. Placunanomia Cumingii. + + 190. Hinge of the same, showing the fissure. + + 191. Hinge of the unattached valve. + + 192. Mulleria. (from Sow. Gen.) + + _Fam._ Rudistis. + + 193. Sphærulites foliacea. (Radiolites is more conical.) + + 194. Calceola Sandalina. + + 196. Birostrites inæquiloba, internal cast of Sphærulites. + + 197. _a._ Crania personata, dorsal valve; _b._ + C. antiquata, interior. + (This would be more properly placed in Brachiopoda.) + + 198. Hippurites Cornucopia, (from Blainville.) + + 199. Hipponyx Cornucopia, attached valve. + + 200. Upper valve of the same. + + _Fam._ Brachiopoda. + + 201. Orbicula lævis. + + 202. Terebratula Psittacea; _a._ anterior margin. + + 203. Atrypa reticularis. Trigonotreta, König. + + 204. Cyrtia exporrecta. + + 205. Delthyris plycotes, (from Dalman.) + + 206. Leptæna depressa, Dalman. Producta, Sow. (from Sow. Gen.) + + 206*. Producta antiquata. + + 207. Orthis basalis, Dalman. Strophomena, Rafinesque. + + 208. Trigonosemus Lyra, König. + + 209. Magas pumilus, Sow. + + 210. Gypidia conchidium, (from Dalman.) + + 211. Interior of the large valve of the same. (from Dalman.) + + 212. Pentamerus Aylesfordii, (from Sow. Min. Con.) + + 213. ---- lævis. + + 214. Spirifer trigonalis. } + } Trigonotreta, König, (from Sow. Gen.) + 215. ---- dorsatus. } + + 216. Thecidium recurvirostrum. + (Here should come Crania, see Rudistes.) + + 217. Pycnodonta radiata, (from Fischer.) + + 218. Hinge of the same. + + 219. Lingula Anatina. + + _Class_, MOLLUSCA. + _Order_, PTEROPODA. + + 220. Atlanta helicialis. + + 221. Cleodora cuspidata. + + 222. Creseis spinifera. + + 223. Cuvieria columella. + + 224. Spiratella limacinea, with animal; Limacella, Lam. Limacina + Cuvier. (from Blainville.) + + 225. Vaginula Daudinii. + + 226. Hyalæa tridentata. Archonte, Montf. + + _Order_, GASTEROPODA. + _Fam._ Phyllidiana. + + 227. Chiton spinosus. + + 228. Chitonellus striatus. (from Sow. Gen.) + + 229. Patella oculus; _a._ anterior. + + 230. Patella pellucida. Helcion, Montf. Ansates, Klein. + + 231. Patelloida Antillarum. Lottia, Gray. + + 231*. Siphonaria Sipho. + + _Fam._ Semiphyllidiana. + + 232. Pleurobranchus membranaceus. + + 233. Umbrella indica. Gastroplax, Bl. + + _Fam._ Calyptracea. + + 234. Calyptræe Equestris. + + 235. ---- extinctorium. + + 236. ---- auriculata. + + 237. ---- Pileus. Infundibulum, Montf. + + 238. Side view of the same. + + 239. Crepidula Porcellana. + + 240. Capulus ungaricus, two views. Pileopsis, Lam. + + 241. Emarginula fissura. + + 242. Parmophorus elongatus. Scutus, Montf. + + 243. Rimula Blainvillii. + + 244. Cemoria Flemingii. + + 245. Fissurella oriens. + + 246. Ancylus fluviatilis. + + _Fam._ Bullæana. + + 247. Bulla fragilis. Akera, Nonnul. + + 248. ---- aperta. Bullæa, Lam. + + 249. ---- aplustre. Aplustre, Schum. + + 250. ---- Naucum. Atys, Montf. + + 251. ---- lignaria. Scaphander, Montf. + + 252. ---- Ampulla. + + 253. ---- lineata. + + _Fam._ Aplysiacea. + + 254. Aplysia Petersoni. + + 255. Dolabella Rumphii. + + _Fam._ Limacinea. + + 256. Parmacella calyculata, Cryptella. Webb. + + 257. Parmacella Olivieri. (from De Ferussac.) + + 258. ---- palliolum. (from De Ferussac.) + + 259. Limax antiquorum. + + 260. Plectophorus corninus. + + 261. Testacella Haliotoidea. + + 262. Helixarion, Cuv. } + } Vitrina, Drap. Cobresia, Haubner. + 263. Helicolimax pellucida. } + + _Order_, TRACHELIPODA. + _Fam._ Colimacea. + + _Sub-genera_ of De Fer. + + 264. Helix brevipes, Drap. Helicophanta. + + 265. Succinea amphibia. } + } Cochlohydra. + 266. ---- patula. Amphibulima, Lam. } + + 267. Helix hæmastoma. Acarus, } + Montf. } + 268. ---- Pomatia. } Helicogena. + } + 269. Streptaxis contusa, Gray.} + } + 270. Another view of the same.} + + 271. Anastoma depressum. } + } + 272. Another view of the same. } + } + 273. Helix nux-denticulata. } Helicodonta. + } + 274. Proserpina nitida. } + } + 275. Polygyra septemvolva. } + } + 276. Another view of the same. } + + 277. Carocolla Lamarckii. } + } Helicigona. + 278. Helix pileus. Geotrochus, Sw. } + + 279. ---- algira. Zonites, Montf. } + } Helicella. + 280. ---- citrina. Naninia, Gray. } + + 281. ---- epistilum Helicostyla. + + 282. Bulinus rosaceus; _a._ apex. } + } + 283. ---- Guadaloupensis; Bulinulus, } + Leach. } Cochlostyla. + 284. ---- Lyonetianus. Gibbus, Montf. } + } + 285. ---- lubricus. Cionella, Jeffreys.} + + 286. Achatina virginea Liguus, Montf. } + } Cochlitoma. + 287. Achatinella, Sw. } + + 288. Polyphemus Glans, Montf. Cochlicopa. + + 289. Bulinus decollatus, in a young state. Cochlicella. + + 290. Azeca tridens, Jeffreys. Turbo tridens, } Cochlogena. + Gmelin. } + + 291. Pupa Uva. } + } + 292. Alæa marginata; Jeffreys. } + } Cochlodonta. + 293. Vertigo pusilla. } + } + 294. Megaspira Ruschenbergiana. } + + 295. Clausilia Macascarensis; _a_, a break, } + to show the clausium. } Cochlodina. + } + 296. Balea fragilis. } + + 297. Auricula Judæ. + + 298. ---- coniformis. Conovulum, Lam. Melampus, Montf. + + 299. Pedipes Adansonii. + + 299*. Scarabæus imbrium. + + 300. Chilina Dombeyana. + + 301. Carychium minimum. + + 302. Partula Australis. + + 303. Cyclostoma ferrugineum. + + 304. ---- Involvulus. Cyclophorus, Montf. + + 305. Nematura Deltæ. + + 306. Helicina major. + + 307. Operculum of the same. + + _Fam._ Lymneana. + + 308. Limnæa stagnalis. + + 309. ---- auricularia. Radix, Montf. + + 310. ---- castanea. Physa, Drap. + + 311. Planorbis corneus. + + 312. Planaria niteus, (from Lea.) + + _Fam._ Melaniana. + + 313. Melania subulata. Melas, Montf. + + 314. Melania prærosa and monodontoides. Anculosa, Say. + + 315. Melanopsis costata. Faunus, Montf. + + 316. Pirena terebralis. + + 317. Pasithæa striata, (from Lea.) + + _Fam._ Peristomata. + + 318. Ampullaria fasciata. Amphibola; _a_, aperture. + + 319. ---- Guinaica. Lanistes, Montf. + + 320. ---- Cornu-arietis. Ceradotes, Guild. + + 321. Paludina Bengalensis. + + 322. Valvata piscinalis. + + _Fam._ Neritacea. + + 323. Navicella elliptica. + + 324. Neritina virginea. Theodoxus, Montf. + + 325. ---- spinosa. Clithon, Montf. + + 326. ---- perversa. Velates, Montf. (from Sow. Gen.) + + 327. Natica mamilla. Polinices, Montf. + + 328. ---- lineata. + + 330. Nerita peloronta. Peloronta, Oken. + + 331. Neritopsis granosa. + + 332. Pileolus plicatus. + + 333. Janthina fragilis. + + _Fam._ Macrostomata. + + 334. Sigaretus concavus. + + 335. Stomatia Phymotis. + + 336. Stomatella imbricata. + + 337. Velutina lævigata. Galericulus, Nonnul. + + 338. Haliotis rubra, young. + + 339. ---- tricostalis, Lam. Padollus, Montf. + + 340. Scissurella elatior, magnified. } + } (from Sow. Gen.) + 341. Pleurotomaria reticulata. } + + _Fam._ Plicacea. + + 342. Pyramidella terebellum. + + 343. Tornatella solidula. Acteon, Montf. + + 344. Monoptygma elegans. (from Lea.) + + _Fam._ Scalariana. + + 345. Vermetus lumbricalis. + + 346. Rissoa reticulata. + + 347. Eulima labiosa. + + 348. ---- marmorata. Bonellia, Desh. + + 349. Cirrus nodosus, Sow. + + 350. Euomphalus pentangulus. (from Sow. Min. Con.) + + 351. Scalaria Pallassii. Aciona, Leach. + + 352. Delphinula laciniata. + + _Fam._ Turbinacea. + + 353. Solarium perspectivum. + + 354. ---- Bifrons. Bifrontia and Omalaxis, Desh. + + 355. Orbis Rotella. (from Lea.) + + 356. Another view of the same. + + 357. Rotella vestiaria, Pitonellus, Montf. + + 358. Trochus stellaris, Lam. Calcar, Montf. Turbo, Sow. + + 359. ---- maculatus. Tectus, Montf. + + 360. ---- agglutinans. Phorus. + + 361. ---- Pharaonis. Clauculus, Montf. + + 362. Margarita tæniata. + + 363. Littorina vulgaris. + + 363*. Assiminea Grayana. + + 364. Lacuna pallidula. + + 365. Planaxis sulcata. + + 366. Monodonta labeo; Odontis, Sow. + + 367. Phasianella variegata. + + 368. Turbo setosus. Marmarostoma, Sw. + + 369. Tuba striata. (from Lea.) + + 370. Turritella imbricata. + + 371. Monotygma, Gray. + + _Fam._ Canalifera. + + 372. Cerithium Aluco, front. + + 374. Nerinea Goodhallii. (from Geol. Trans.) + + 375. Triphora plicata. (from Deshayes.) + + 376. End view of the same. + + 377. Potamis muricata. Pyrazus, Montf. Tympanostomata, Schum. + + 378. Cerithium Telescopium. _Gen._ Telescopium. + + 379. Pleurotoma Babylonia; _a, a_, extremities of the axis. + + 381. ---- strombiformis, Clavatula, Lam. + + 382. Turbinella corniger. Scolymis, Sw. + + 383. ---- polygona. Polygonum, Schum. + + 384. Spirillus. _Gen._ Pyrella, Sw. Turbinella spirillus, Auct. + + 385. Cancellaria reticulata. + + 386. Fasciolaria Trapezium. + + 387. Fusus Colus; _a_, anterior of the aperture; p, posterior. + + 388. Pyrula perversa. Fulgur, Montf. + + 389. ---- papyracea. Rapanus, Schum. Bulbus, Humph. Rapella, Sw. + + 390. ---- Ficus. Ficula, Sw. + + 391. Struthiolaria straminea. + + 393. Ranella ranina. Apollon, Montf. + + 394. ---- neglecta. Bufo, Montf. + + 395. Murex inflatus. Chicoreus, Montf. + + 396. ---- haustellum. Brontes, Montf. + + 397. Typhis tubifer. (from Deshayes.) + + 398. Triton pilearis. + + 399. ---- cutaceus. Aquillus, Montf. + + 400. ---- Lotorium. Lotorium, Montf. + + 401. ---- anus. Persona, Montf. + + _Fam._ Alatæ. + + 402. Rostellaria curvirostrum. + + 403. ---- columbaria. Hippochrenes, Montf. (from Sow. Gen.) + + 404. ---- Pes-pelicani. Aporrhais, Petiver. + + 405. Pteroceras aurantiacum. + + 406. Strombus pugilis. + + _Fam._ Purpurifera. + + 407. Cassidaria echinophora. Morio, Montf. + + 408. Side view of the outer lip, to shew the canal. + + 409. Oniscia Oniscus. Cassidara. + + 410. Cassis tuberosa, reduced. + + 411. ---- erinaceus. Cassidea, Sw. + + 412. ---- testiculus. Cypræcassis, Stutchbury. + + 413. Ricinula horrida. Sistrum, Montf. + + 414. Purpura persica. + + 415. Tritonidea (_Pollia_, Gray.) articularis. + + 416. Phos senticosa. + + 417. Monoceros crassilabrum. + + 418. Concholepas Peruviana. + + 419. Harpa ventricosa. + + 420. Dolium maculatum. + + 421. Buccinum undatum; _a_, anterior of the aperture; _p_, posterior. + + 422. ---- papillosum. Alectrion, Montf. + + 423. Nassa arcularia. + + 424. ---- neritoidea. Cyclops, Montf. + + 425. Cyllene, Gray. + + 426. Eburna Zeylanica. + + 427. Bullia vittata. + + 428. Terebra maculata. Subula, Bl. + + 429. Trichotropis bicarinata. + + _Fam._ Columellata. + + 430. Columbella mercatoria. + + 431. Mitra plicaria; _c_, termination of the columella. + + 432. Conohelix marmorata. + + 433. Voluta Vespertilio. Cymbiola, Sw. + + 434. Cymba porcina. + + 435. Melo Æthiopicus. + + 436. Volutilithes spinosus. + + 437. Marginella Glabella. Glabella, Sw. Cucumis, Klein. + + 438. ---- persicula. Volutella, Sw. Persicula, Schum. + + 439. Volvaria concinna. + + _Fam._ Convolutæ. + + 440. Ovulum Ovum. + + 441. ---- verrucosum. Calpurnus, Montf. + + 442. ---- Volva. Radius, Montf. + + 443. ---- gibbosum. Ultimus, Montf. + + 444. Cypræovulum capense. + + 445. Cypræa arabica, back. + + 446. The same, front. + + 447. Cypræa Algoensis. Luponia, Gray, front. + + 449. ---- Pediculus. Trivia, Gray, back. + + 450. The same, front. + + 451. Terebellum convolutum. Seraphs, Montf. + + 452. ---- subulatum, front. + + 454. Erato Mangeriæ. + + 455. Ancillaria glabrata. Anolax, Brongn. + + 456. ---- cinnamonea. + + 457. Oliva Maura. + + 458. ---- subulata. Hiatula, Sw. + + 459. Conus nocturnus. Rhombus, Montf. + + 460. ---- Nussatella. Hermes, Montf. + + 461. ---- Textile. Cylinder, Montf. + + 462. ---- geographus. Rollus, Montf. + + _Order._ CEPHALOPODA. + _First Division._ Polythalamous Cephalopoda. + _Fam._ Orthocerata. + + 463. Amplexus coralloides. (from Sow. Min. Con.) + + 464. Orthoceratites annulatus. + + 465. Nodosaria æqualis. + + 466. Belemnites, with the outer coat broken to shew the alveole. + + 467. ---- portion of the alveole separated. + + 468. ---- hastatus. Hibolithes, Montf. (from Blainville.) + + 469. Conularia quadrisulcata. + + 470. Conilites pyramidatus, (from Blainville.) + + _Fam._ Lituacea. + + 471. Spirula Peronii. + + _Fam._ Nautilacea. + + 472. Nummulites buticularis, outside. Helicites, Bl. Camerina, Brookes. + + 473. The same inside, to shew the chambers. + + 474. Nautilus pompilius, young. See Frontispiece. + + 475. Simplegas sulcata. + + 476. Endosiphonites. (from Camb. Philos. Trans.) + + _Fam._ Ammonacea. + + 477. Ammonoceras. (from Blainville.) + + 478. Ammonites; _a_, break in the shell, showing the sinuous septa. + + 479. Orbulites crassus. Globulites, Nonnul. Angulites, Montf. reduced. + + 479*. ---- discus. Aganides, Montf. + + 480. Goniatites striatus. + + 481. Scaphites æqualis. + + 482. Crioceratites Duvallii. + + 483. Turrilites tuberculatus. + + 484. Baculites Faujasii. Portion near the centre. + + 484*. Hamites cylindricus; _a_, internal cast of part of the shell; + _b_, hollow external cast of the remainder. + + _Second Division._ Monothalamous Cephalopoda. + + 485. Argonauta Argo. + + 486. Bellerophon tenuifasciata. (from Sow. Gen.) + + 487. The same, shewing the dorsal keel. + + _Order._ HETEROPODA. + + 488. Carinaria Mediterranea. + + * * * * * + +EXPLANATION OF THE NEW PLATES. + + _Order._ SESSILE CIRRIPEDES. + + 489. Pyrgoma monticularia. _Sub-genus_, Daracia, Gray, back and + front. + + 490. The same, in situ. + + _Fam._ Myaria. + + 491. Lyonsia Norvegica. Anatina, Nonnul. Inside view of both valves. + + 492. Outside, with the valves closed. + + 493. Næra longirostrum. Anatina longirostris, Lam. Inside of both + valves. + + 494. Outside, with both valves closed. + + 495. A smaller species of Næra, shewing the inequality of the valves. + + _Fam._ Mactracea. + + 496. Amphidesma tennis. Abra, Leach. + + 497. Ervillia nitens. + + _Fam._ Corbulacea. + + 498. Potamomya, of some authors. A fresh-water shell resembling + Corbula. Outside, valves closed. + + 499. Inside of both valves. + + Fluviatile Conchacea. + + 500. Cyclas amnica. Pera, Leach. + + _Fam._ Cardiacea. + + 501. Cardilia semisulcata. Isocardia semisulcata, Lam. Internal view. + + 502. External view of the same valve. + + 503. Cardium apertum. Papyridea, Sw. + + 504. The same, shewing the umbones. + + 505. Pleurorynchus, fossil, (from Mineral Conchology.) + + _Fam._ Phyllidiana. + + 506. Chiton fascicularis. Phakellopleura, Guild. + + 507. ---- amiculatus. Amicula, Gray. + + _Fam._ Calyptracea. + + 508. Scutella, Brod. Internal view. + + 509. External view of the same. + + 510. Ancylus, a reversed species, illustrating the genus Velletia, + Gray. Enlarged view. + + 511. The same, natural size. + + 512. Pedicularia. Enlarged figure, (copied from Swainson.) + + 513. The same, natural size, growing on coral. + + _Fam._ Colimacea. + + 514. Achatina? octona. Macrospira, Guild. + + 515. Stenopus cruentatus, Guild. Under side. + + 516. ---- lividus. + + 517. Helix, the aperture covered by the epiphragm. + + 518. Pupa secale, Drap. Abida, Leach. + + 519. ---- pagoda. Gonidomus, Sw. + + 520. Truncatella, enlarged figure. + + 521. The same, natural size. + + 522. Auricula caprella. _Gen._ Caprella, Nonnul. Front view. + + 523. The same, dorsal view. + + 524. Pupina vitrea. + + 526. ---- antiquata. + + 527. ---- Namezii. + + 528. ---- lubrica. Callia? Gray. + + 529. Cyclostoma, a pupiform species. Megalomastoma, Guild. + + 530. ---- Planorbulum. Cyclotus, Guild. + + 531. ---- a similar species, with the complicated notch at the + posterior part of the aperture. Pterocyclos, Gray. + + 532. Helicina acutissima, nobis. View of the under side. Trochatella, + Sw. + + 533. The same in profile. + + 534. } + } + 535. } Strophostoma, Desh. three views. + } + 536. } + + _Fam._ Peristomata. + + 537. Paludina impura. Bithinia, Gray? + + 538. Ampullaria avellana. Thallicera, Sw. Ampullarina? + + 539. A species of Ampullaria having a thickened ledge on which the + shelly operculum rests. Pachystoma, Guild. changed to + Pachylabra, Sw. + + _Fam._ Plicacea. + + 540. Ringicula, Desh. A fossil species, front view. + + 541. Back view of the same. + + _Fam._ Turbinacea. + + 542. Turbo nicobaricus. Chrysostoma, Sw. + + 543. Trochus Iris. Elenchus, Humph. + + _Fam._ Purpurifera. + + 544. Purpura vexilla. _Gen._ Vexilla, Sw. + + 545. Priamus. Achatina priamus, Auct. The propriety of placing it in + this family will depend upon the correctness of the statement + made by Dr. Beck that this shell is marine, and possesses an + operculum. + + 546. Purpura crispata. Polytropa, Sw. + + 547. Pseudoliva plumbea. Gastridium, Sow. + + _Fam._ Canalifera. + + 548. Fusus longevus. Clavalithes, Sw. + + 549. ---- bulbiformis. Leiostoma, Sw. + + 550. Pyrella, Sw. Turbinella Spirillus, Auct. + + 551. Pleurotoma lineata. Tomella, Sw. + + 552. Pyrula melongena. _Gen._ Myristica, Sw. + + 553. Murex vitulinus. _Gen._ Vitulina, Sw. + + 554. Typhis Sowerbii. + + 555. A brown variety of the same. + + 556. Typhis Cumingii. + + _Fam._ Columellata. + + 557. Voluta Vexillum. Harpula, Sw. + + 558. Mitra monodonta. Mitreola, Sw. + + 559. ---- bicolor. Mitrella, Sw. + + 560. Columbella nitidella. _Gen._ Nitidella, Sw. + + _Fam._ Convolutæ. + + 561. Oliva volutella. _Gen._ Lamprodoma, Sw. + + 562. ---- maura. + + 563. Cypræa Globulus. _Gen._ Globularia, Sw. + + 564. ---- pulchella, fossil. _Gen._ Cyprædia, Sw. + +THE END. + + * * * * * + + +TABLE OF LAMARCK'S CONCHOLOGICAL SYSTEM. + + _Classes of + Invertebrated _Orders._ _Families._ _Genera._ + Animals._ + + ANNELIDES. Sedentary _Dorsalia_ Siliquaria. + _Maldania_ Dentalium. + _Serpulacea_ Serpula, Spirorbis, + Galeolaria, Vermilia, + Magilus. + + CIRRIPEDES. Sessile Tubicinella, Coronula, + _Multivalve._ Balanus, Acasta, Pyrgoma, + Creusia. + + Pedunculated Anatifer, Pollicipes, + Cineras, Otion. + + CONCHIFERA Dimyaria _Tubicolaria_ Aspergillum, Clavagella, + _Bivalve._ Fistulana, Septaria, Teredo, + Teredina. + _Pholadaria_ Pholas, Gastrochæna. + _Solenacea_ Solen, Panopæa, Glycimeris. + _Myaria_ Mya, Anatina. + _Mactracea_ Lutraria, Mactra, + Crassatella, Erycina, + Ungulina, Solemya, + Amphidesma. + _Corbulacea_ Corbula, Pandora. + _Lithophagidæ_ Saxicava, Petricola, + Venerirupis. + _Nymphacea_ Sanguinolaria, Psammobia, + Psammotæa, Tellina, + Tellinides, Corbis, Lucina, + Donax, Capsa, Crassina. + _Fluviatile Cyclas, Cyrena, Galathæa. + Conchacea_ + _Marine Conchacea_ Cyprina, Cytheræa, Venus, + Venericardia. + _Cardiacea_ Cardium, Cardita, + Cypricardia, Hiatella, + Isocardia. + _Arcacea_ Cucullæa, Arca, + Pectunculus, Nucula. + _Trigonacea_ Trigonia, Castalia. + _Nayades_ Unio, Hyria, Anodon, + Iridina. + _Chamacea_ Diceras, Chama, Etheria. + + Monomyaria _Tridacnacea_ Tridacna, Hippopus. + _Mytilacea_ Modiola, Mytilus, Pinna. + _Malleacea_ Crenatula, Perna, Malleus, + Avicula, Meleagrina. + _Pectenides_ Pedum, Lima, Plagiostoma, + Pecten, Plicatula, + Spondylus, Podopsis. + _Ostracea_ Gryphæa, Ostræa, Vulsella, + Placuna, Anomia. + _Rudistes_ Sphærulites, Radiolites, + Calceola, Birostrites, + Discina, Crania. + _Brachiopoda_ Orbicula, Terebratula, + Lingula. + + MOLLUSCA Pteropoda Hyalæa, Cleodora, Limacina, + _Univalve._ Cymbulia. + + Gasteropoda _Phyllidiana_ Chiton, Chitonellus, + Patella. + _Semiphyllidiana_ Pleurobranchus, Umbrella. + _Calyptracea_ Parmophorus, Emarginula, + Siphonaria, Fissurella, + Pileopsis, Calyptræa, + Crepidula, Ancylus. + _Bulleana_ Bulla, Bullæa. + _Aplysiacea_ Aplysia, Dolabella. + _Limacinea_ Parmacella, Limax, + Testacella, Vitrina. + + Trachellipoda _Colimacea_ Helix, Carocolla, Anastoma, + Helicina, Pupa, Clausilia, + Bulinus, Achatina, Succinea, + Auricula, Cyclostoma. + _Lymneana_ Planorbis, Physa, Lymnæa. + _Melaniana_ Melania, Melanopsis, Pirena. + _Peristomata_ Valvata, Paludina, + Ampullaria. + _Neritacea_ Navicella, Neritina, Nerita, + Natica, Janthina. + _Macrostomata_ Stomatia, Stomatella, + Haliotis. + _Plicacea_ Tornatella, Pyramidella. + _Scalariana_ Vermetus, Scalaria, + Delphinula. + _Turbinacea_ Solarium, Rotella, Trochus, + Monodonta, Turbo, Planaxis, + Phasianella, Turitella. + _Canalifera_ Cerithium, Pleurotoma, + Turbinella, Cancellaria, + Fasciolaria, Fusus, Pyrula, + Ranella, Murex, Triton. + _Alata_ Rostellaria, Strombus, + Pteroceras. + _Purpurifera_ Cassidaria, Cassis, + Ricinula, Purpura, + Monoceros, Concholepas, + Harpa, Dolium, Buccinum, + Eburna, Terebra. + _Columellata_ Columbella, Mitra, Voluta, + Marginella, Volvaria. + _Convoluta_ Ovulum, Cypræa, Oliva, + Ancillaria, Conus. + + Polythalamous _Orthocerata_ Belemnites, Orthoceras, + Cephalopoda Nodosaria, Hippurites, + Conilites. + _Lituacea_ Spirula, Spirolina, Lituola. + _Cristacea_ Renulina, Cristellaria, + Orbiculina. + _Spherulacea_ Miliola, Gyrogona, Melonia, + (Microscopic.) + _Radiolacea_ Rotalites, Lenticulina, + Placentula, (Micros.) + _Nautilacea_ Discorbites, Siderolites, + Polystomella, Vorticialis, + Nummilites, Nautilus. + _Ammonacea_ Ammonites, Ammonoceras, + Turrilites, Baculites. + + Monothalamous Argonauta. + Cephalopoda + + Heteropoda Carinaria. + + * * * * * + +TABLE OF THE CONCHOLOGICAL SYSTEM OF DE BLAINVILLE. + + Key. + 1 = TYPE MALACOZOARIA + 2 = SUB-TYPE MALENTOZOARIA + + CLASSES + A = CEPHALOPHORA + B = PARACEPHOLOPHORA DIOICA + C = PARACEPHALOPHORA MONOICA + D = PARACEPHALOPHORA HERMAPHRODITA + E = ACEPHALOPHORA + F = NEMATOPODA + G = POLYPLAXIPHORA + + ORDERS + a = Cellulacea + b = Polyphalamacea + c = Siphonobranchiata + d = Asiphonibranchiata + e = Pulmobranchiata + f = Chismobranchiata + g = Monopleurobranchiata + h = Aporobranchiata + i = Nucleobranchiata + j = Cirrobranchiata + k = Cervicobranchiata + l = Scutibranchiata + m = Palliobranchiata + n = Rudistes + o = Lamellibranchiata + + _Classes._ _Families._ _Genera._ + _Orders._ + + {_Planulacea_ Renulina, Peneroplis. + { + { a {_Sphærulacea_ {Miliola, Pollontes, Melonia, + { { {Saracenaria, Textularia. + { { + { {_Nummulacea_ {Nummulites, Orbiculina, + { {Helicites, Placentula, + { {Vorticialis, Siderolites. + { A { + { { {_Orthocerata_ {Belemnites, Conularia, + { { { {Conilites, Orthoceras, + { { { {Baculites. + { { { + { { {_Lituacea_ {Icthysarcolites, Lituola, + { { { {Spirula, Spirolina, + { { { {Hamites, Ammonoceras. + { { { + { { b {_Cristacea_ Crepidulina, Oreas, Linthuris. + { { + { {_Ammonacea_ {Discorbis, Scaphites, + { { {Ammonites, Simplegas. + { { + { {_Nautilacea_ {Polystomelle, Nautilus, + { { {Lenticulina. + { { + { {_Turbinacea_ Cibicides, Rotalia. + { { + { {_Turriculacea_ Turrilites. + { + { {Pleurotoma, Rostellaria, + { {Fusus, Pyrula, + { {_Siphonostomata_ {Fasciolaria, Turbinella, + { { {Columbella, Triton, + { { {Struthiolaria, Ranella, + { { {Murex. + { { + { { {Cerithium, Pyrena, Melanopsis, + { { {Planaxis, Subula, Terebra, + { { {Eburna, Buccinum, Harpa, + { { c {_Entomostomata_ {Dolium, Cassis, Cassidaria, + { { { {Ricinula, Cancellaria, + { { { {Purpura, Concholepas, Terebra, + { { { {Mitra + { { { + {_Univalves_ { { { {Strombus, Conus, Terebellum, + { { { {_Angyostomata_ {Oliva, Ancillaria, Voluta, + { { { {Mitra, Marginella, Volvaria, + { { { {Cypræa, Ovulum. + { { { + { { { {_Goniostomata_ Solarium, Trochus. + { { B { { + { { { { {Monodonta, Turbo, + { { { { {Pleurotomaria, Littorina, + { { { { {Delphinula, Cyclostoma, + { { { {_Cricostomata_ {Paludina, Valvata, Scalaria, + { { { { {Proto, Turitella, Vermetus, + { { { { {Siliquaria, Magilus. + { { { { + { { { d {_Hemicyclostomata_{Nerita, Neritina, Clithon, + { { { {Velates, Pileolus, Navicella, + { { { {Natica. + { { { + { { {_Ellipsostomata_ {Helicina, Ampullaria, Melania, + { { { {Rissoa, Phasianella, + { { { {Pleurocerus. + { { { + { { {_Oxystomata_ Janthina. + { { + { { {_Limnacea_ Limnæa, Physa, Planorbis. + { { { + { { {_Auriculacea_ {Auricula, Pedipes, Tornatella, + { { C e { {Tomogerus, Pyramidella. + { { { + { { { {Succinea, Bulinus, Achatina, + { { { _Limacinea_ {Clausilia, Pupa, Partula, + { { {Helix, Vitrina, Testacella, + { { {Parmacella, Limacella, Limax. + { { + { { f {Sigaretus, Cryptostomata, + { { {Stomatella, Velutina. + { { + 1 { { {_Sub-aplysiaca_ Pleurobranchus. + { { { + { { g {_Aplysiaca_ Aplysia, Dolabella. + { { { + { { {_Patelloidea_ Umbrella, Siphonaria. + { { { + { { {_Akera_ Bulla, Bellerophon, Sormetus. + { { + { { h _Thecosomata_ Hyalæa, Cleodora, Cymbulia. + { { + { { {_Nectopoda_ Carinaria. + { { i { + { { {_Pteropoda_ {Atlanta, Spiratella, + { { {Argonauta. + { { + { { { j Dentalium. + { { { + { { { {_Retifera_ Patella. + { { D { k { + { { {_Branchifera_ {Fissurella, Emarginula, + { { {Parmophorus. + { { + { { {_Otides_ Haliotis, Ancylus. + { { l { + { {_Calyptracea_ {Crepidula, Calyptræa, + { {Capulus, Hipponyx, Notrema. + { + { {Lingula, Terebratula, + { { {Strophomena, Dianchora, + { { m {Thecidium, Plagiostoma, + { { {Podopsis, Orbicula, Crania. + { { + { { n {Sphærulites, Hippurites, + { { {Radiolites, Birostrites, + { { {Calceola. + {_Bivalves_ E { + { {_Ostracea_ {Anomia, Placuna, Ostræa, + { { {Gryphæ. + { { + { {_Sub-ostracea_ {Spondylus, Plicatula,, + { { {Hinnites, Pecten, Pedum,, + { { {Lima. + { { + { { {Vulsella, Malleus, Avicula, + { {_Margaritacea_ {Perna, Crenatula, Inoceramus, + { { {Catillus, Pulvinites, + { { {Gervillia. + { { + { {_Mytilacea_ Pinna, Mytilus. + { { + { {_Arcacea_ Arca, Pectunculus, Nucula. + { { + { {_Sub-mytilacea_ Anodon, Unio, Cardita. + { { + { {_Chamacea_ {Chama, Diceras, Etheria, + { { {Tridacna, Hippopus, + { { {Isocardium, Trigonia. + { { + { o { {Cardium, Donax, Tellina, + { {Lucina, Cyclas, Cyprina, + {_Conchacea_ {Mactra, Erycina, Crassatella, + { {Venerirupis, Venus, + { {Coralliophaga, Clotho, + { {Corbula, Sphænia, Ungulina. + { + { {Pandora, Anatina, Thracia, + { {Mya, Lutricola, Psammocola, + { {Soletellina, Sanguinolaria, + {_Pylorides_ {Solenocurtus, Solen, Solemya, + { {Panopæa, Glycimeris, + { {Saxicava, Byssomya, + { {Rhomboides, Gastrochæna, + { {Clavagella, Aspergillum + { + {_Adesmacea_ {Pholas, Teredina, Teredo, + {Fristulana, Septaria. + + {_Lepadicea_ {Gymnolepas, Pentalepas, + { {Polylepas, Litholepas. + { F { + { {_Balanidea_ {Balanus, Acasta, Octhosia, + 2 _Multivalves_{ {Conia, Creusia, Pyrgoma, + { {Chthalamis, Coronula, + { {Chelnobia, Cetopirus, + { {Diadema, Tubicinella. + { + { G _Seriales_ {Chiton, Chitonellus. + +[Illustration: Fig. 1 to 33.] + +[Illustration: Fig. 34 to 59.] + +[Illustration: Fig. 60 to 78.] + +[Illustration: Fig. 79 to 100.] + +[Illustration: Fig. 101 to 116.] + +[Illustration: Fig. 117 to 126 and 128.] + +[Illustration: Fig. 127 and 129 to 141.] + +[Illustration: Fig. 142 to 152.] + +[Illustration: Fig. 153 to 166. 165 next plate.] + +[Illustration: Fig. 165. 167 to 182.] + +[Illustration: Fig. 183 to 213. 195. cancelled.] + +[Illustration: Fig. 214 to 242.] + +[Illustration: Fig. 243 to 278.] + +[Illustration: Fig. 279 to 317.] + +[Illustration: Fig. 318 to 348.] + +[Illustration: Fig. 349 to 381. 377. 378. in the next.] + +[Illustration: Fig. 377. 378. 382 to 397. 383 in the next.] + +[Illustration: Fig. 383. 398 to 406. 409.] + +[Illustration: Fig. 407 to 425. 409 in the last.] + +[Illustration: Fig. 426 to 443.] + +[Illustration: Fig. 444 to 462.] + +[Illustration: Fig. 463 to 479.] + +[Illustration: Fig. 479* to 488.] + +[Illustration: Fig. 489 to 513.] + +[Illustration: Fig. 514 to 545.] + +[Illustration: Fig. 546 to 564.] + + * * * * * + + +WORKS ON NATURAL HISTORY, + +SOLD AT REDUCED PRICES + +BY + +HENRY G. BOHN, + +YORK STREET, COVENT GARDEN. + +ARTIS'S (E. T.) ANTEDILUVIAN PHYTOLOGY, illustrated by a Collection of the +FOSSIL REMAINS OF PLANTS, peculiar to the Coal Formations of Great Britain, +selected for their Novelty and Interest, from upwards of a Thousand +Specimens now in the possession of the Author, and systematically +described, with the view of facilitating the Study of this important Branch +of Geology: including Remarks on the Systems of _Count Sternberg_, _Baron +Schlotheim_, _Professor Martius_, and _Mons. Brongniart_; also +Communications from PROFESSOR BUCKLAND, and other eminent Geologists, 4to. +_with 25 plates_, (published at 2l 10s) _cloth boards_, 15s + +1838 + +BAUER'S ILLUSTRATIONS OF THE GENERA OF FERNS, in which the characters of +each Genus are displayed in the most elaborate manner, in a series of +magnified dissections and figures, HIGHLY FINISHED IN COLOURS, after the +beautiful Drawings of FRANCIS BAUER, Esq. Botanical Draughtsman to Her +Majesty; with descriptive letter-press by Sir WILLIAM JACKSON HOOKER, parts +1 to 11, imperial 8vo. + +1838-42 + +To be completed in 12 parts, price 12s each. + +BEECHEY.--BOTANY OF CAPTAIN BEECHEY'S VOYAGE, comprising an Account of the +Plants collected by Messrs. Lay and Collie, and other Officers of the +Expedition, during the Voyage to the Pacific and Behring's Strait, +performed in her Majesty's ship _Blossom_, under the command of Captain F. +W. BEECHEY, by Sir William Jackson Hooker and G. A. W. Arnott, Esq. +_illustrated by 100 plates, beautifully engraved, complete in 10 parts_, +4to. _price 15s each._ + +1831-41 + +---- ZOOLOGY OF CAPTAIN BEECHEY'S VOYAGE, compiled from the Collections and +Notes of Captain Beechey and the Scientific Gentlemen who accompanied the +Expedition, by Dr. Richardson, N. A. Vigors, Esq., G. T. Lay, Esq., E. T. +Bennett, Esq., Richard Owen, Esq., John Edward Gray, Esq., W. Sowerby, Esq. +and the Rev. Dr. Buckland, 4to. _illustrated by 47 finely coloured plates +by Sowerby, extra cloth bds._ 5l 5s + +1839 + +BOASE'S (DR. H. S. _Sec. Roy. Geol. Soc. of Cornwall_) TREATISE ON PRIMARY +GEOLOGY, being an Examination, both Practical and Theoretical, of the older +Formations, 8vo. _cuts_, (published at 12s) _cloth bds._ 5s + +1834 + + "An admirable work, involving some of the most refined discussions of + which Geology is susceptible."--_Literary Gazette._ + +BURMEISTER'S MANUAL OF ENTOMOLOGY, translated from the last German edition +by W. E. SHUCKARD, Member of the Entomological Society, &c. with +considerable and important additions by the Author, (communicated expressly +for this edition,) and many original Notes by the translator. ILLUSTRATED +BY THIRTY-THREE ENGRAVINGS ON STEEL, in which are represented ABOVE FIVE +HUNDRED subjects, _chiefly generic distinctions, anatomical sections, +organs, eggs, larvæ, &c. of Insects; together with a beautifully coloured +frontispiece_, 1 thick vol. 8vo. _comprising above 650 closely printed +pages_, (published at 1l 1s _in bds._) _hf. bd. morocco_, 15s + +1836 + +CURTIS'S FLORA LONDINENSIS; revised and improved by George Graves, extended +and continued by Sir W. Jackson Hooker; comprising the History of Plants +indigenous to Great Britain, their Uses, Economy, and various interesting +Particulars, with Alphabetical, Linnæan, and other Indexes; the Drawings +made by Sydenham Edwards and Lindley, 5 vols. royal folio (or 109 parts), +containing 647 plates, _exhibiting the full natural size of each plant, +with magnified dissections of the parts of fructification, &c. all +beautifully coloured_, (pub. at 87l 4s in parts) 26l 5s + +---- the same, _elegantly hf. bd. morocco, top edges gilt_, 30l + + This is the only extensive work on the Indigenous Botany of this + country, which gives well-coloured representations of the plants _in + their full natural size_. + +CUVIER.--HISTOIRE NATURELLE DES MAMMIFERES, avec des Figures Originales +Enluminées, Dessinées d'après les Animaux vivants, ouvrage publié sous +l'Autorité de l'Administration du Muséum d'Histoire Naturelle, par F. +CUVIER et E. GEOFFROY SAINT-HILAIRE, 3 vols. royal folio, _containing 360 +exquisitely coloured plates of animals_, (published at 47l 5s) _very +splendidly half-bd. turkey morocco, gilt edges_, 24l + + *** The advertiser having purchased of the Parisian publishers all the + remaining copies of this magnificent work, is enabled to offer them at + the above extremely reduced price. + + This is the finest work on mammiferous animals ever published in any + country, and has always been considered, both for the high talent + displayed in the text and the extremely beautiful execution of the + plates, which resemble drawings, as taking the first place in the class + to which it belongs. As very few copies remain for sale, and the price + is so extremely low, the book must soon become scarce, and rise in + value. + + "Un des ouvrages les plus exacts et les mieux exécutés que l'on ait + encore donnés sur les Mammifères."--_Brunet._ + + "It is unnecessary to dilate upon the splendid style in which this work + is brought out, or on the ability and fidelity that characterise as + well the figures as the descriptions contained in it, since these must + be well known to all who have seen any of the numbers. It will + doubtless form the standard work of reference for the Mammalia. + Necessarily too expensive for general circulation, public libraries, + and the collections of the rich can alone possess it; but to these it + is indispensable; while the manner in which it is executed renders it + worthy of a place by the side of their most costly and elegant + volumes."--_Zoological Journal._ + +DENNY'S MONOGRAPHIA PSELAPHIDARUM ET SCYDMÆNIDARUM BRITANNIÆ; or an Essay +on the British Species of the Genera Pselaphus of Herbst, and Scydmænus of +Latreille, in which those Genera are subdivided, and all the Species +hitherto discovered in Great Britain are accurately described and arranged, +with an Indication of the Situations in which they are usually found, 8vo. +_with 14 coloured plates, containing 40 Figures of Beetles_, (pub. at 1l +1s) _extra cloth bds_. 12s + +Norwich, 1825 + + This volume has for some time been considered scarce, and sold for more + than the published price. + +DONOVAN'S NATURAL HISTORY OF THE INSECTS OF INDIA, new edition, +considerably enlarged, brought down to the present state of the Science, +with alphabetical and systematic Indices, etc. by J. O. WESTWOOD, Esq. +F.L.S. 4to. _with 58 plates, containing upwards of 120 exquisitely coloured +figures_, (published at 6l 6s) _extra cloth bds. elegantly gilt_, 2l 5s + +1842 + +---- NATURAL HISTORY OF THE INSECTS OF CHINA, new edition, considerably +enlarged, brought down to the present state of the Science, with +alphabetical and systematic Indices, etc. by J. O. WESTWOOD, Esq. F.L.S. +4to. _with 50 plates, containing upwards of 120 exquisitely coloured +figures_, (published at 6l 6s) _extra cloth bds. elegantly gilt_, 2l 5s + +1842 + + "Donovan's works on the Insects of India and China, are splendidly + illustrated and extremely useful,"--_Naturalist._ + + "The entomological plates of our countryman Donovan, are highly + coloured, elegant, and useful, especially those contained in his quarto + volumes (Insects of India and China) where a great number of species + are delineated for the first time."--_Swainson._ + +DRURY'S ILLUSTRATIONS OF FOREIGN ENTOMOLOGY, wherein are exhibited UPWARDS +OF SIX HUNDRED EXOTIC INSECTS, of the East and West Indies, China, New +Holland, North and South America, Germany, &c. very few of which are +figured in any other work; engraved with the greatest accuracy by the +celebrated MOSES HARRIS, Author of the _Aurelian_, &c. all most correctly +and beautifully coloured from the original specimens, NEW AND MUCH IMPROVED +EDITION, with the following important additions:--the Modern Names, Generic +and Specific Characters, Synonymes of later Naturalists; Accounts of the +Economy, Habitations, and Food of many of the Insects; and Scientific and +Alphabetic Indexes, by J. O. WESTWOOD, Esq. F.L.S. Secretary of the +Entomological Society, &c. 3 vols. 4to. _150 plates_, (originally published +at 15l 15s) _hf. bd. morocco, uncut_, 6l 16s 6d + +1837 + +---- the same, _richly bound in green morocco, gilt edges_, 9l 9s + + "The exquisite work of Drury displays the complete insect in a degree + of perfection that leaves nothing to be desired."--_Sir James E. + Smith._ + + This new edition is exquisitely coloured, and must rank high among the + luxurious publications of the age. Its literary and scientific + excellence is in keeping with its attractive appearance. + + "A few years ago, a new edition, with impressions from the original + plates, was published under the editorial care of Mr. Westwood, by Mr. + Henry Bohn the Bookseller. It is not easy to speak of this edition in + terms of too high commendation. The colouring, executed from the + original drawings, under the superintendence of one of the ablest + entomological artists of the day, is faithful to nature, and owing to + the fineness of the paper and a particular process to which it has been + subjected, possesses a lustre and beauty which were unattainable at the + time when the original edition appeared. The text has been in a great + measure re-written; ample and accurate descriptions introduced; the + modern nomenclature applied, and the intricacies of synonomy + unravelled; indexes and much original matter added, and the whole work + adapted to the present advanced state of the science."--_Sir W. + Jardine._ + +EDWARDS'S (GEORGE) NATURAL HISTORY OF BIRDS, NEW EDITION, 7 vols. royal +4to. WITH 362 PLATES, BEAUTIFULLY COLOURED LIKE DRAWINGS, (published at +30l) _hf. bd. morocco, uncut, top edges gilt_, 14l 14s + +1802-6 + +---- the same, LARGE PAPER, WITH THE PLATES BEAUTIFULLY COLOURED LIKE +DRAWINGS, 7 vols. folio, (published at 50l) _hf. bd. morocco, uncut, gilt +tops, rare_, 21l + +GREVILLE'S CRYPTOGAMIC FLORA, comprising the Principal Species found in +Great Britain, inclusive of all the New Species recently discovered in +Scotland, 6 vols. royal 8vo. _with 360 beautifully coloured plates_, +(published at 16l 16s) _neatly half bound morocco_, 8l 8s + +1823-8 + + This, though a complete work in itself, forms AN ALMOST INDISPENSABLE + SUPPLEMENT TO THE THIRTY-SIX VOLUMES OF SOWERBY'S ENGLISH BOTANY, WHICH + DOES NOT COMPREHEND CRYPTOGAMEOUS PLANTS. It is one of the most + scientific and best executed works on Indigenous Botany ever produced + in this country. + + "A truly admirable work, which may be honestly designated as so + excellent, that nothing can be found to compete with it in the whole + range of Indigenous Botany; whether we consider the importance of its + critical discussions, the accuracy of the drawings, the minuteness of + the analyses, or the unusual care which is evident in the publishing + department. After expressing this opinion, we are sure the work will + need no further recommendation with the public." + + _Loudon's Gardener's Magazine._ + +HARRIS'S AURELIAN; a Natural History of English Moths and Butterflies, +together with the Plants on which they feed; also a faithful Account of +their respective Changes, their usual haunts when in the winged state, and +their standard Names as established by the Society of Aurelians, new and +greatly improved edition, containing a complete Modern Nomenclature of all +the Species figured in the work, and further Accounts of their Economy, by +J. O. WESTWOOD, Esq. F.L.S. etc., in 1 vol. sm. folio, _with 44 plates, +containing above 400 figures of Moths, Butterflies, Caterpillars, etc. and +the Plants on which they feed, exquisitely coloured after the original +drawings, hf. bd. morocco_, 4l 4s + + This beautiful work is the only one which contains our English Moths + and Butterflies of the full natural size, in all their changes of + Caterpillar, Chrysalis, &c. with the plants on which they feed. + +HOOKER'S (SIR W. J.) FLORA BOREALI-AMERICANA; or the Botany of British +North America; compiled principally from the Plants collected by Dr. +Richardson and Mr. Drummond on the late Northern Expeditions, under the +command of Captain Sir John Franklin; to which are added, by permission of +the Horticultural Society, those of Mr. Douglas and other Naturalists, +_illustrated by 240 plates, and a large map, beautifully engraved_; +COMPLETE IN 12 PARTS, forming 2 handsome vols. royal 4to. each part 1l 1s + +1829-40 + +HOOKER'S BOTANICAL MISCELLANY; containing Figures and Descriptions of +Plants, which recommend themselves by their novelty, rarity, or history, or +by the uses to which they are applied in the Arts, in Medicine, and in +Domestic Economy, together with occasional Botanical Notices and +information, including many valuable Communications from distinguished +Scientific Travellers; complete in 9 parts, forming 3 thick vols. royal +8vo. _with 153 plates, many finely coloured_, (published at 5l 5s) _gilt +cloth_, 2l 12s 6d + +1830-33 + +HOOKER'S MUSCI EXOTICI; or Figures and Descriptions of new or little known +Foreign Mosses, and other Cryptogamic Subjects, 2 vols. 8vo. _176 plates_, +(published at 4l 4s) _cloth bds._ 1l 11s 6d + +1818-20 + +---- the same, _with the plates beautifully coloured_, (published at 8l 8s) +_cloth bds._ 3l 3s + +HOOKER'S BRITISH JUNGERMANNIÆ, being a History and Description, with +coloured Figures, of each Species of the Genus, with Microscopical Analysis +of the parts, _new edition, nearly ready_, 4to. _88 finely coloured plates_ + +HOPE'S (REV. W.) COLEOPTERIST'S MANUAL, Part 1, containing the Lamellicorn +Insects of Linneus and Fabricius, 8vo. _plates, bds._ 7s + +1837 + +---- COLEOPTERIST'S MANUAL, Part 2, containing the Predaceous Land and +Water Beetles of Linneus and Fabricius, 8vo. _beautifully coloured plates, +cloth_, 10s 6d + +1838 + +HUMBOLDT ET BONPLAND, RECUEIL D'OBSERVATIONS DE ZOOLOGIE ET D'ANATOMIE +COMPAREE, faites dans l'Intérieur du Nouveau Continent, &c. 8 parts in 1 +vol. imperial 4to. VELLUM PAPER, _with 34 plates, of which 21 are +beautifully coloured_, (published at 10l 10s) _cloth bds. lettered_, 15s + +1811 + +JARDINE AND SELBY. Illustrations of Ornithology, by Sir W. Jardine, and P. +J. Selby, Esq., with the co-operation of J. E. Bicheno, Esq., J. G. +Children, Esq., Major-General Hardwicke, Dr. Horsfield, R. Jameson, Esq., +Sir T. Stamford Raffles, N. A. Vigors, Esq., and John Gould, Esq. 3 vols. +royal 4to. _with 150 accurately engraved figures of new and interesting, or +rare species, of Birds, beautifully coloured, also a duplicate set of the +same, uncoloured; in all 300 plates_, (published at 15l 15s) _neatly half +bound, top edges gilt_, 6l 6s + +Edinb. 1829, &c. + + "This is a very excellent and valuable work, as indeed the talent + employed on it sufficiently ensures. The plates are beautifully + coloured, and the letter-press accurately and well written. We strongly + recommend it to our scientific readers."--_Neville Wood._ + +LAMARCK'S CONCHOLOGY, containing a complete Translation of his Descriptions +of both the recent and Fossil Genera, Illustrated by 22 highly-finished +Lithographic Plates, comprising nearly 400 accurate Figures of Shells drawn +by J. Mawe, edited by EDMUND A. CROUCH, F.L.S. royal 4to. (published at 1l +11s 6d) _in extra cloth boards_, 10s 6d + +1827 + +---- the same, WITH THE PLATES BEAUTIFULLY COLOURED, (published at 3l 3s) +_elegantly bound in gilt cloth_, 1l 11s 6d + + "This work will be found admirably adapted for the purpose for which it + is intended, viz. to introduce to the student the improved system of + Conchology founded by the celebrated French naturalist Lamarck, which + is done in a clear and concise manner, by giving a short yet adequate + description of the various classes, orders, families, and genera, + composing the system; accompanied with illustrations of characteristic + and generally well known species, drawn from nature. We can strongly + recommend it to the attention of all those who feel interested in this + department of natural history. The plates, twenty-two in number, are + thickly though not confusedly studded with figures--indeed, + considerable taste is displayed in their arrangement; they are + beautifully coloured, and have more the appearance of highly finished + drawings than merely tinted engravings, and on the whole, it reflects + great credit upon the artist-author." + + _Literary Gazette._ + +LATHAM'S GENERAL HISTORY OF BIRDS, being the Natural History and +Description of all the Birds (above four thousand) hitherto known or +described by Naturalists, with the Synonymes of preceding Writers; the +second enlarged and improved edition, comprehending all the discoveries in +Ornithology subsequent to the former publication, and a General Index, 11 +vols. 4to. _with upwards of 200 exquisitely coloured plates, elegantly hf. +bd. morocco_, 12l 12s + +Winchester, 1821-28 + +The Index sold separately, price 10s 6d in boards. + + This celebrated work was published at twenty-five guineas in boards, + with the plates coloured in a very inferior manner. The present copies + are all COLOURED LIKE HIGHLY FINISHED DRAWINGS, with studious accuracy, + under the direction of several eminent Ornithologists, and most of the + subjects have been compared with living or preserved specimens in the + Museums and Gardens of London. Copies coloured in this manner would not + have been published at less than FIFTY GUINEAS. Indeed the few copies + of the old edition formerly coloured by Miss Stone, similar in + execution but inferior in accuracy to the present, have been sold as + high as from fifty to one hundred guineas at the sales of Col. Stanley, + John Dent, Esq. and Sir Mark Sykes. + + "No scientific works on Natural History ever obtained so much celebrity + as those of our venerable countryman Dr. Latham. His _General History + of Birds_, which is an enlargement of his _Synopsis_, is undoubtedly + the MOST USEFUL AND VALUABLE WORK OF ITS CLASS, THAT HAS YET APPEARED + as it contains exact scientific descriptions of every bird known at the + time." + + _Neville Wood._ + +LEWIN'S (J. W.) NATURAL HISTORY OF THE BIRDS OF NEW SOUTH WALES, collected, +engraved, and faithfully painted after Nature, by JOHN WILLIAM LEWIN, late +of Paramatta, New South Wales; third and greatly improved edition, with an +Index of the Scientific Names and Synonymes to the present time (1838), +contributed by Mr. Gould, Mr. Eyton, and other scientific gentlemen, folio, +_with 27 plates, beautifully coloured_, (published at 4l 4s) _neatly hf. +bd. morocco_, 2l 2s + +1838 + + "Admirable figures, full of truth and nature; accompanied by valuable + observations on the habits and economy of the birds."--_Swainson._ + + "According to the first ornithologists of the day, these plates are of + permanent value."--_Wood._ + +LINDLEY'S BRITISH FRUITS; or Figures and Descriptions of the most Important +Varieties of Fruit Cultivated in Great Britain, 3 vols. royal 8vo. +_containing 152 most beautifully coloured plates, chiefly by Mrs. Withers, +Artist to the Horticultural Society_, (published at 10l 10s) _elegantly hf. +bd. green morocco extra, gilt edges_, 5l 5s + +1841 + + This is an exquisitely beautiful work. Every plate is like a highly + finished drawing, similar to those in the Horticultural Transactions. + +LINDLEY'S LADIES' BOTANY; or a Familiar Introduction to the Study of the +Natural System of Botany, _new edition_, 12mo. _with numerous wood-cuts_, +(published at 12s) _elegantly bound in cloth, with gilt back and sides_, 7s + +1841 + +---- the same, _with the plates coloured, extra gilt cloth_, 12s + + "The want of a popular Introduction to the study of Botany on the + improved natural system has been completely removed by this volume of + Dr. Lindley's. It is accurate in its science, graceful in its style, + and familiar in its language; it enables the student to take some + common, or easily accessible plant, as the representative of each + natural family, to examine its several parts, to compare them with the + plates, and learn their uses from the descriptions; when he has done + this with care, and understood, and remembered what he has done, he + will be a Botanist; if not a learned one, at least acquainted with all + the fundamental facts of the science." + + _Athenæum._ + + "We are infinitely indebted to Professor Lindley for leading us so far + in the study of Botany in a plain and intelligible way. A multitude of + plates, a clear text, and a most judicious and agreeable arrangement, + render this introduction to perhaps the most innocent and delightful of + all studies, truly acceptable." + + _Literary Gazette._ + +MANTELL'S FOSSILS OF THE SOUTH DOWNS, or ILLUSTRATIONS of the GEOLOGY of +SUSSEX, royal 4to. _with 42 plates_, (published at 3l 3s) _extra cloth +bds_. 2l 2s + +1822 + + "My attention was first drawn to these remains by Mr. Mantell, who has + illustrated the subject in his excellent work on the Fossils of the + South Downs." + + _Parkinson's Organic Remains._ + + "For the detailed history of the Organic Remains of the Wealden + formation, see Mr. Mantell's highly instructive and accurate volume on + the Geology of Sussex." + + _Buckland's Bridgewater Treatise._ + +MARTIN'S (P. I.) GEOLOGICAL MEMOIR ON A PART OF WESTERN SUSSEX, with some +Observations upon Chalk-Basins, the Weald-Denudation, and +Outliers-by-Protrusion, 4to. _large map and coloured plates_, (published at +1l) _cloth bds._ 12s + +1828 + +MUDIE'S (ROBT.) HISTORY OF BRITISH BIRDS, or the Feathered Tribes of the +British Islands, 2 vols. 8vo. _second edition, the plates beautifully +coloured_, (published at 1l 8s) _extra cloth bds. elegantly gilt on the +backs_, 16s + +1835 + + "This is, without any exception, the most truly charming work on + Ornithology which has hitherto appeared, from the days of Willughby + downwards. Other authors describe, Mudie paints; other authors give the + husk, Mudie the kernel. We most heartily concur with the opinion + expressed of this work by Leigh Hunt (a kindred spirit) in the first + few numbers of his right pleasant _London Journal_. The descriptions of + Bewick, Pennant, Lewin, Montagu, and even Wilson, will not for an + instant stand comparison with the spirit-stirring emanations of Mudie's + 'living pen,' as it has well been called. We are not acquainted with + any author who so felicitously unites beauty of style with strength and + nerve of expression--he does not specify, he paints." + + _Wood's Ornithological Guide._ + + "The '_Feathered Tribes_' is indeed an EXQUISITE WORK, and + unquestionably the best that has yet appeared on the habits of our + native birds, in that it is scarcely second to those of Wilson and + Audubon. Mudie is the most accurate observer of nature,--Selby + excepted, and he treats not exclusively of habits--consequently the + '_Feathered Tribes_' deserves a distinguished place on the shelves of + the philosophic ornithologist."--_Ornithologist's Text Book._ + +PARKINSON'S ORGANIC REMAINS OF A FORMER WORLD, being an Examination of the +Mineralized Remains of the Vegetables and Animals of the Antediluvian +World, generally termed Extraneous Fossils, 3 vols. 4to. _with 54 coloured +plates by Sowerby, exhibiting above 700 Fossil Remains_, (published at 10l +10s) _extra cloth bds._ 4l 4s + + This distinguished work is continually referred to by Dr. Buckland in + his Bridgewater Treatise. + + "A work on the same subject, equally elegant, comprehensive, and + impartial, does not exist in English; nor, as far as we know, in any + other language. It is written in a plain, intelligible, and equal + style, such as may, with pleasure, be perused by all classes of + readers."--_British Critic._ + + "'Organic Remains of a Former World,' replete with interest and + instruction."--_Dr. Mantell._ + +PARKINSON'S INTRODUCTION TO THE STUDY OF FOSSIL ORGANIC REMAINS; especially +those found in the British Strata, intended to aid the Student in his +Inquiries respecting the Nature of Fossils, and their Connection with the +Formation of the Earth, 3rd edition, 8vo. _illustrated by 220 Fossil +Specimens_, (published at 12s) _extra cloth bds._ 8s + + "In this well-printed volume, which may be called a grammar of + Oryctology, Mr. Parkinson has comprised an extensive and well-arranged + variety of information on the subject of fossil organic remains; + supplying to the learner, an easy and complete introductory manual; and + to the well-informed, a text-book of convenient reference. The graphic + illustrations are copious and distinct."--_Eclectic Review._ + +PURSH'S FLORA AMERICÆ SEPTENTRIONALIS; or a Systematic Arrangement and +Description of the Plants of North America; containing, besides what have +been described by preceding Authors, many new and rare species, collected +during twelve years travels and residence in that country, 2 vols. 8vo. +_with 24 plates_, (published at 1l 16s) _cloth_, 14s + +---- the same, _with the plates beautifully coloured_, (published at 2l 12s +6d) _cloth_, 1l 1s + +1814 + +RICHARDSON'S FAUNA BOREALI-AMERICANA, or ZOOLOGY of NORTH AMERICA, +containing Descriptions of the Subjects collected in the late Northern +Expeditions under the command of Captain Sir John Franklin, by JOHN +RICHARDSON, M.D., WM. SWAINSON, Esq., and the Rev. WM. KIRBY, published +under the Authority of the Right Hon. the Secretary of State for Colonial +Affairs, _with numerous beautifully coloured plates_, 4 vols. 4to. +(published at 9l 9s) _cloth_, 5l 15s 6d + +_The following may be had separately_: + + Vol. 2. Birds, by Swainson, 50 _coloured plates_, (published at 4l 4s) + _cloth_, 2l 2s + + 3. Fishes, by Richardson, _coloured plates_, 1l 4s + + 4. Insects, by Kirby, _coloured plates_, 1l 4s + + "We cannot speak in too high terms of admiration with regard to that + splendid national production the _Fauna Boreali-Americana_. It is + undoubtedly the best work of its kind that has ever appeared, and will, + we expect, long remain so."--_Neville Wood._ + + "Whether we consider the condensed mass of novel information, the + number of species for the first time introduced to our systems, the + accuracy of the scientific details, the beauty and correctness of the + illustrations and the whole appearance of the book, it reflects the + highest degree of credit upon the authors, the artist, and the + government."--_Loudon._ + +SELBY'S MAGNIFICENT WORK, THE FIGURES OF BRITISH BIRDS, containing an exact +and faithful representation, in their full natural size, of all the known +species found in Great Britain, _383 Figures in 228 beautifully coloured +plates_, 2 vols, elephant folio, (published at 105l) _elegantly hf. bd. +morocco, full gilt back and gilt edges, with glazed paper to the plates_, +31l 10s + +1834 + +---- the same, _plain plates_, (published at 31l 10s) _hf. bd. calf_, 15l +15s + + The grandest work on Ornithology published in this country, the same + for British Birds that Audubon's is for the birds of America. Every + figure, excepting in a very few instances of extremely large birds, is + of the full natural size, beautifully and accurately drawn, with all + the spirit of life. + + "Every individual of the Falcon and Owl Families would make a PERFECT + PICTURE OF ITSELF, so beautifully and correctly are they executed: THEY + HAVE CERTAINLY NEVER BEEN EQUALLED EVEN BY GOULD AND AUDUBON." + + _Ornithologist's Text Book._ + + "The author has been most successful, especially in the larger birds, + and it would be impossible to improve on any of the _Raptores_, which + for fidelity, boldness, and spirit, are unequalled--every feather is + distinct, yet beautifully blended."--_Wood's Ornithological Guide._ + +SELBY'S ILLUSTRATIONS OF BRITISH ORNITHOLOGY, 2 vols. 8vo. Second Edition, +(published at 1l 1s) _in bds._ 12s + +1833 + + This is the most complete Scientific manual of British Ornithology yet + published. Every known British Bird is enumerated, with an ample + description of its plumage, habits, etc., the scientific as well as + familiar names given by different Naturalists, and references to all + those who have figured it. + + "SELBY'S IS THE MOST MASTERLY WORK THAT HAS EVER APPEARED ON THE BIRDS + OF BRITAIN, AND IS QUITE INDISPENSABLE TO EVERY ORNITHOLOGIST." + + _Ornithologist's Text Book._ + +SOWERBY'S MANUAL OF CONCHOLOGY, containing a complete Introduction to the +Science, illustrated by upwards of 650 FIGURES OF SHELLS, etched on +Copper-plates, in which the most characteristic examples are given of all +the Genera established up to the present time, arranged in Lamarckian +Order, accompanied by copious explanations; observations respecting the +geographical or geological distribution of each; tabular views of the +Systems of Lamarck and De Blainville; a Glossary of technical terms, &c. +&c. NEW EDITION, CONSIDERABLY ENLARGED AND IMPROVED, WITH NUMEROUS +WOOD-CUTS IN THE TEXT, NOW FIRST ADDED, 8vo. _cloth_, 1l 5s + +1842 + +---- the same, COLOURED PLATES, _gilt cloth_, 2l 5s + + This is the only work which, in a moderate compass, gives a + comprehensive view of Conchology, according to the present advanced + state of the science. It will not only be found useful to all who wish + to acquire an elementary acquaintance with the subject, but also to the + proficient, as a book of reference. + +SWAINSON'S ZOOLOGICAL ILLUSTRATIONS, or Original Figures and Descriptions +of New, Rare, or interesting Animals, selected chiefly from the Classes of +Ornithology, Entomology, and Conchology, and arranged on the Principles of +Cuvier and other modern Zoologists, BOTH SERIES COMPLETE, 6 vols. royal +8vo. _containing_ 318 FINELY COLOURED PLATES, (published at 16l 16s) +_unbound_, 8l 8s + +---- the same, _very neatly half-bound morocco, uncut,_ 9l 9s + + *** _This fine work was published in parts at 4s 6d each. Either of the + Series, in 3 vols. may be had separately, at £4. 4s each in parts, or + £4. 14s 6d half-morocco; but separate Parts can only be sold at the + original price._ + + This highly esteemed publication, by one of the most eminent Zoologists + of the age, has long been considered very scarce, and from its being + the sole property of the author has not hitherto been sold under the + published price. In consequence, however, of his leaving England, he + has thought it advisable to dispose of the whole stock to the + advertiser, who now offers the complete copies, which are very few in + number, at the low prices affixed. + + The whole of the figures are original, having been drawn by Mr. + Swainson himself, chiefly from specimens in his own collection, and + coloured under his immediate inspection. They are universally allowed + to be unrivalled for beauty and fidelity. + + "It might, perhaps, almost be deemed presumption to offer any remarks + on a work emanating from the pen and pencil of, undoubtedly, the first + Ornithologist of the day, but we feel it our duty to give our readers + _some_ idea of the contents of the _Zoological Illustrations._ It will + be sufficient, if we mention that his coloured figures of birds are + almost unequalled,--they are certainly not surpassed. The figures are + beyond conception lovely and delicate, and it only remains for us to + remark, that EVERY PHILOSOPHIC ORNITHOLOGIST MUST POSSESS THE + ZOOLOGICAL ILLUSTRATIONS, IF INDEED THEY ARE NOW TO BE HAD."--_Wood's + Ornithologist's Text Book._ + +SWAINSON'S EXOTIC CONCHOLOGY, or Figures and Descriptions of Rare, +Beautiful, or Undescribed Shells, with new Letter-press Descriptions, 6 +parts, royal 4to. _containing_ 94 LARGE AND BEAUTIFULLY COLOURED FIGURES OF +SHELLS, (published at 5l 5s) _elegantly half-bound morocco, gilt edges_, 2l +12s 6d + +Each of the Six Parts may be had separately, at 8s per part. + + "Many of the most rare and beautiful species of this singularly elegant + genus (the Volutes), have been figured by Swainson in the first plates + of his _Exotic Conchology_, with a verisimilitude that has never been + equalled, and probably never will be excelled, by any artist. This + talent, combined with his scientific knowledge as a naturalist, must + render the above work the most eminent of its kind in this + country."--_Dubois._ + +SWAINSON'S ORNITHOLOGICAL DRAWINGS, being figures of the rarer and most +interesting BIRDS OF BRAZIL. Complete in 7 parts, royal 8vo. CONTAINING +SEVENTY-EIGHT BEAUTIFULLY COLOURED PLATES, (published at 3l 13s 6d) +_elegantly hf. bd. morocco, in one volume_, 2l 5s + + This exceedingly beautiful work is in very few even of the most + complete ornithological libraries, as only 175 copies were printed, and + Mr. Swainson refused to sell any excepting to those who had originally + subscribed for them. + + "Mr. Swainson's name stands so deservedly high, both as an + ornithologist and an artist, that, in introducing this splendid work to + the notice of our readers, we shall simply say that we consider it in + every respect worthy of its author. Farther commendation we feel would + be superfluous."--_Loudon._ + +WALLICH, PLANTÆ ASIATICÆ RARIORES, 12 parts, imperial folio, _coloured +plates_, (published at 36l) _sewed_, 25l + +WILSON'S AMERICAN ORNITHOLOGY, or Natural History of the Birds of the +United States; with a Continuation by Charles Lucien Bonaparte, Prince of +Musignano, NEW AND ENLARGED EDITION, completed by the insertion of above +One Hundred Birds omitted in the original Work, and illustrated by valuable +Notes, with an interesting Life of the Author, by Sir WILLIAM JARDINE, +Bart., F.R.S.E., F.L.S. 3 vols. 8vo. _with a fine portrait of Wilson, and +97 plates, exhibiting 363 figures of Birds, accurately engraved, and most +beautifully coloured, on glazed drawing paper_, (published at 10l 10s) +_elegantly hf. bd. morocco, top edges gilt_, 4l 4s + +1832 + + "The valuable Notes and interesting Life of Wilson added to this new + edition are from the pen of Sir William Jardine, a Naturalist of + congenial mind in feeling and talent. The plates are better executed + than those in the American Edition, and the greatest possible attention + has been paid to accuracy of colouring. Altogether we have rarely seen + a more valuable work on Natural History, and not one more + entertaining."--_Literary Gazette._ + + "The splendid work of Alexander Wilson will always be regarded as a + subject of pride by his adopted country, as it certainly is by that + which gave him birth (Scotland)."--_Chambers._ + + "The History of American Birds, by Alexander Wilson, is equal in + elegance to the most distinguished of our own splendid works on + Ornithology."--_Cuvier._ + + "This is by far the best edition of the American Ornithology, both on + account of the beautiful plates and the interesting notes of the + editor. Every ornithologist must, of course, possess the work, and he + should if possible procure this edition." + + _Neville Wood._ + +WOODVILLE'S MEDICAL BOTANY, containing Systematic Descriptions of Medicinal +Plants, with a circumstantial Account of their Effects, and of the Diseases +in which they have been most successfully employed, THIRD EDITION, to which +is added a SUPPLEMENTARY VOLUME, by SIR WILLIAM JACKSON HOOKER, +_illustrated by 310 coloured plates by Sowerby_, 5 vols. 4to. (published at +10l 10s) _half-bound morocco, uncut_, 5l 5s + +---- The Fifth or Supplementary Volume, entirely by Sir W. J. HOOKER, with +30 Coloured Plates, to complete the old editions, (published at £2. 12s. +6d.) cloth boards, £1. 11s. 6d. + + No well-stored English Library should be without Woodville's Medical + Botany, a work of long-established reputation, and the best on a + subject which must, more or less, be interesting to every man of + inquiry. It contains accurate figures and descriptions of all the + plants used in English medicine, and is of such authority with + professional men, as to be almost as essential to them as the + Pharmacopoeia itself. Subsequent publications of a similar kind, though + with Woodville as their text-book, have fallen greatly short of the + original, as well in comprehensiveness of plan, as in accuracy of + delineation and correctness of colouring. It having long been a matter + of regret that so excellent a work, from the want of a new edition, + should remain so much behind the present state of pharmaceutical + science, Sir William undertook to supply this defect, by adding a + Supplementary Volume, containing all the new and acknowledged + discoveries, and all the plants added to the Pharmacopoeias since the + publication of the work in 1810. New plates have likewise been given + for the _Cinchonas_, and other plants, which were not properly + identified in the time of Woodville; and new letter-press or _errata_ + for such descriptions as were deficient or incorrect. All these + alterations and additions have been given in the supplementary or fifth + volume, preserving everything contained in the original work, inclusive + even of the incorrect plates and letter-press, though duplicate, + leaving it to the purchaser's option either to cancel or retain them, + as he pleases. + + * * * * * + + +_Just Published, in Imperial 8vo. price, Coloured, £1 5s. Plain, 16s._ + +Part I + +OF THE + +THESAURUS CONCHYLIORUM, + +BY + +G. B. SOWERBY, JUN. + +Containing descriptions of all the species hitherto known of the following +Genera of SHELLS; Helicina, Pupina, Rostellaria, Aporrhais, Struthiolaria +and Strombus, accompanied by 300 highly finished coloured engravings. + +This work is commenced, and will be continued on a more extensive, +complete, and economic plan than has hitherto been attempted. It is +intended to be so complete as to supersede the necessity of keeping an +extensive conchological library, or of consulting a variety of books for +the purpose of identifying species. IT WILL FORM A COMPLETE CONCHOLOGICAL +LIBRARY IN ITSELF. + +The vast increase in the number of species, either undescribed or published +in miscellaneous works, and voyages; the difficulty of obtaining such +works, or of naming species without them, and the confusion of Synonymes +which has been the result, are facts which prove the importance of the +present undertaking. The facilities enjoyed by the author, in having access +to several of the most important collections; and obtaining the fullest +information respecting the localities of subjects by those who have sought +them in their native abodes, will, it is trusted, enable him to supply a +generally acknowledged desideratum. He hopes to do this in such a manner as +to fulfil the expectations of his friends, who may rest assured that +neither pains nor expense will be spared to ensure the correctness, +completeness, and beauty of the work. + +The plan of the work is as follows:--it will consist of a complete series +of Monographs of Genera of Shells. All the species and varieties of each +genus will be described and figured. The essential characters will be given +in latin. The explanations and general information will be expressed in +English. The figures of average sized shells will be reduced to half the +real diameter; those of larger size will be still further reduced; and +those of small size will be represented of the natural dimensions. The size +of the book is Imperial octavo. The paper, printing, engraving and +colouring of the best description. A part, containing several Monographs +will appear every third month, or oftener if possible, the price of each +part to depend upon the number of figures which it contains, at the rate of +one penny for each figure. + +THE 2nd PART WILL APPEAR ON THE 1st OF AUGUST. + + * * * * * + +THE + +CONCHOLOGICAL ILLUSTRATIONS, + +_Or, figures of hitherto unfigured recent Shells, Part 1 to 200_, + +PRICE, 1S. 6D. EACH, + +May now be had with Indices complete. None of the Genera contained in this +work will be given in the Thesaurus until all the other Genera are +exhausted. + + * * * * * + +SOWERBY, NATURALIST. + +No. 50, GREAT RUSSELL STREET, BLOOMSBURY. + + * * * * * + + +CORRECTIONS MADE TO PRINTED TEXT + +ANOMIA: "sub-equilateral" corrected from "sub-equilaternal" + +ARGONAUTA: "Cephalopoda" corrected from "Cepholopoda" + +ib. "the Argonaut is the testaceous part" corrected from "... Agonaut ..." + +HALIOTIS: "oblique" corrected from "obilque" + +POLYLEPAS: "lepas, rock." corrected from "lepas, Linn." + +RHINODOMUS: "No internal groove" corrected from "... grove" + +65. "Panopæa Australis" corrected from "... Ausrtalis" + +Heading: "Fam. Brachiopoda" corrected from "... Brachipoda" + + + + + + +End of the Project Gutenberg EBook of A Conchological Manual, by +George Brettingham Sowerby + +*** END OF THE PROJECT GUTENBERG EBOOK 43417 *** |