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diff --git a/old/3772-h/files/ch14.html b/old/3772-h/files/ch14.html new file mode 100644 index 0000000..4baa855 --- /dev/null +++ b/old/3772-h/files/ch14.html @@ -0,0 +1,935 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- saved from url=(0036)http://../Lyell/The Student's Elements of Geology --> +<html> +<head> +<meta name="generator" content="HTML Tidy, see www.w3.org"> +<title>The Student's Elements of Geology: Title</title> +<meta content="text/html; charset=iso-8859-1" http-equiv= +"Content-Type"> +<meta content="MSHTML 5.00.2919.6307" name="GENERATOR"> +<link rel="stylesheet" href="geology.css" type="text/css"> +</head> +<body> +<p><b>The Student’s Elements of Geology</b></p> + +<hr> +<p class="page"><a name="page 211">[ 211 ]</a></p> + +<p> </p> + +<center><b>Chapter XIV</b><br> +<br> +MIOCENE PERIOD—UPPER MIOCENE.</center> + +<p class="intro">Upper Miocene Strata of France—Faluns of +Touraine. — Tropical Climate implied by Testacea. — +Proportion of recent Species of Shells. — faluns more ancient +than the Suffolk Crag. — Upper Miocene of Bordeaux and the +South of France. — Upper Miocene of Œningen, in +Switzerland. — Plants of the Upper Fresh-water Molasse. +— Fossil Fruit and Flowers as well as Leaves. — Insects +of the Upper Molasse. — Middle or Marine Molasse of +Switzerland. — Upper Miocene Beds of the Bolderberg, in +Belgium. — Vienna Basin. — Upper Miocene of Italy and +Greece. — Upper Miocene of India; Siwalik Hills. — +Older Pliocene and Miocene of the United States.</p> + +<p><b>Upper Miocene Strata of France—Faluns of +Touraine.</b>—The strata which we meet with next in the +descending order are those called by many geologists “Middle +Tertiary,” for which in 1833 I proposed the name of Miocene, +selecting the “faluns” of the valley of the Loire, in +France, as my example or type. I shall now call these falunian +deposits Upper Miocene, to distinguish them from others to which +the name of Lower Miocene will be given.</p> + +<p>No British strata have a distinct claim to be regarded as Upper +Miocene, and as the Lower Miocene are also but feebly represented +in the British Isles, we must refer to foreign examples in +illustration of this important period in the earth’s history. +The term “faluns” is given provincially by French +agriculturists to shelly sand and marl spread over the land in +Touraine, just as similar shelly deposits were formerly much used +in Suffolk to fertilise the soil, before the coprolitic or +phosphatic nodules came into use. Isolated masses of such faluns +occur from near the mouth of the Loire, in the neighbourhood of +Nantes, to as far inland as a district south of Tours. They are +also found at Pontlevoy, on the Cher, about seventy miles above the +junction of that river with the Loire, and thirty miles south-east +of Tours. Deposits of the same age also appear under new mineral +conditions near the towns of Dinan and Rennes, in Brittany. I have +visited all the localities above enumerated, and found the beds on +the Loire to consist principally of sand and marl, in which are +shells and corals, some entire, some rolled, and others in minute +fragments. In certain districts, as at Doué, in the +Department of Maine and Loire, ten miles south-west</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 212">[ 212 ]</a></p> + +<p>of Saumur, they form a soft building-stone, chiefly composed of +an aggregate of broken shells, bryozoa, corals, and echinoderms, +united by a calcareous cement; the whole mass being very like the +Coralline Crag near Aldborough, and Sudbourn in Suffolk. The +scattered patches of faluns are of slight thickness, rarely +exceeding fifty feet; and between the district called Sologne and +the sea they repose on a great variety of older rocks; being seen +to rest successively upon gneiss, clay-slate, various secondary +formations, including the chalk; and, lastly, upon the upper +fresh-water limestone of the Parisian tertiary series, which, as +before mentioned <a href="ch9.html#page 142">(p. 142)</a>, +stretches continuously from the basin of the Seine to that of the +Loire.</p> + +<img src="../images1/fig136.jpg" width="170" height="235" alt= +"Fig. 136: Dinotherium giganteum." align="left"> + +<p>At some points, as at Louans, south of Tours, the shells are +stained of a ferruginous colour, not unlike that of the Red Crag of +Suffolk. The species are, for the most part, marine, but a few of +them belong to land and fluviatile genera. Among the former, <i> +Helix turonensis)</i> (<a href="../images/fig38.jpg">Fig. 38</a>) is +the most abundant. Remains of terrestrial quadrupeds are here and +there intermixed, belonging to the genera Dinotherium (Fig. 136), +Mastodon, Rhinoceros, Hippopotamus, Chæropotamus, Dichobune, +Deer, and others, and these are accompanied by cetacea, such as the +Lamantin, Morse, Sea-calf, and Dolphin, all of extinct species.</p> + +<p>The fossil testacea of the faluns of the Loire imply, according +to the late Edward Forbes, that the beds were formed partly on the +shore itself at the level of low water, and partly at very moderate +depths, not exceeding ten fathoms below that level. The molluscan +fauna is, on the whole, much more littoral than that of the +Pliocene Red and Coralline Crag of Suffolk, and implies a shallower +sea. It is, moreover, contrasted with the Suffolk Crag by the +indications it affords of an extra-European climate. Thus it +contains seven species of Cypræa, some larger than any +existing cowry of the Mediterranean, several species of <i>Oliva, +Ancillaria, Mitra, Terebra, Pyrula, Fasciolaria,</i> and <i> +Conus.</i> Of the cones there are no less than eight species, some +very large, whereas the only European cone now living is of +diminutive size. The genus <i>Nerita,</i> and many others, are also +represented by individuals</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 213">[ 213 ]</a></p> + +<p>of a type now characteristic of equatorial seas, and wholly +unlike any Mediterranean forms. These proofs of a more elevated +temperature seem to imply the higher antiquity of the faluns as +compared with the Suffolk Crag, and are in perfect accordance with +the fact of the smaller proportion of testacea of recent species +found in the faluns.</p> + +<p>Out of 290 species of shells, collected by myself in 1840 at +Pontlevoy, Louans, Bossée, and other villages twenty miles +south of Tours, and at Savigné, about fifteen miles +north-west of that place, seventy-two only could be identified with +recent species, which is in the proportion of twenty-five per cent. +A large number of the 290 species are common to all the localities, +those peculiar to each not being more numerous than we might expect +to find in different bays of the same sea.</p> + +<p>The total number of species of testaceous mollusca from the +faluns in my possession is 302, of which forty-five only, or +fourteen per cent, were found by Mr. Wood to be common to the +Suffolk Crag. The number of corals, including bryozoa and +zoantharia, obtained by me at Doué and other localities +before adverted to, amounts to forty-three, as determined by Mr. +Lonsdale, of which seven (one of them a zoantharian) agree +specifically with those of the Suffolk Crag. Some of the genera +occurring fossil in Touraine, as the corals Astrea and <i> +Dendrophyllia</i>, and the bryozoan <i>Lunulites</i>, have not been +found in European seas north of the Mediterranean; nevertheless, +the zoantharia of the faluns do not seem to indicate, on the whole, +so warm a climate as would be inferred from the shells.</p> + +<p>It was stated that, on comparing about 300 species of Touraine +shells with about 450 from the Suffolk Crag, forty-five only were +found to be common to both, which is in the proportion of only +fifteen per cent. The same small amount of agreement is found in +the corals also. I formerly endeavoured to reconcile this marked +difference in species with the supposed co-existence of the two +faunas, by imagining them to have severally belonged to distinct +zoological provinces or two seas, the one opening to the north and +the other to the south, with a barrier of land between them, like +the Isthmus of Suez, now separating the Red Sea and the +Mediterranean. But I now abandon that idea for several reasons; +among others, because I succeeded in 1841 in tracing the Crag fauna +southward in Normandy to within seventy miles of the Falunian type, +near Dinan, yet found that both assemblages of fossils retained +their distinctive characters, showing no signs of any blending of +species or transition of climate.</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 214">[ 214 ]</a></p> + +<p>The principal grounds, however, for referring the English Crag +to the older Pliocene and the French faluns to the Upper Miocene +epochs, consist in the predominance of fossil shells in the British +strata identifiable with species not only still living, but which +are now inhabitants of neighbouring seas, while the accompanying +extinct species are of genera such as characterise Europe. In the +faluns, on the contrary, the recent species are in a decided +minority; and most of them are now inhabitants of the +Mediterranean, the coast of Africa, and the Indian Ocean; in a +word, less northern in character, and pointing to the prevalence of +a warmer climate. They indicate a state of things receding farther +from the present condition of Central Europe in physical geography +and climate, and doubtless, therefore, receding farther from our +era in time.</p> + +<img src="../images1/fig137.jpg" width="134" height="300" alt= +"Fig. 137: Voluta Lamberti." align="left"> + +<p>Among the conspicuous fossils common to the faluns of the Loire +and the Suffolk Crag is a variety of the <i>Voluta Lamberti</i>, a +shell already alluded to <a href="../images1/fig123.jpg">(Fig. +123).</a> The specimens of this shell which I have myself collected +in Touraine, or have seen in museums, are thicker and heavier than +British individuals of the same species, and shorter in proportion +to their width, and have the folds on the columella less oblique, +as represented in Fig. 137.</p> + +<p><b>Upper Miocene of Bordeaux and the South of +France.</b>—A great extent of country between the Pyrenees +and the Gironde is overspread by tertiary deposits of various ages, +and chiefly of Miocene date. Some of these, near Bordeaux, coincide +in age with the faluns of Touraine, already mentioned, but many of +the species of shells are peculiar to the south. The succession of +beds in the basin of the Gironde implies several oscillations of +level by which the same wide area was alternately converted into +sea and land and into brackish-water lagoons, and finally into +fresh-water ponds and lakes.</p> + +<p>Among the fresh-water strata of this age near the base of the +Pyrenees are marls, limestones and sands, in which the eminent +comparative anatomist, M. Lartet, has obtained a great number of +fossil mammalia common to the faluns of the Loire and the Upper +Miocene beds of Switzerland, such as <i>Dinotherium giganteum</i> +and <i>Mastodon angustidens</i>; also</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 215">[ 215 ]</a></p> + +<p>the bones of quadrumana, or of the ape and monkey tribe, which +were discovered in 1837, the first of that order of quadrupeds +detected in Europe. They were found near Auch, in the Department of +Gers, in latitude 43° 39' N. About forty miles west of +Toulouse. They were referred by MM. Lartet and Blainville to a +genus closely allied to the Gibbon, to which they gave the name of +<i>Pliopithecus.</i> Subsequently, in 1856, M. Lartet described +another species of the same family of long-armed apes +(<i>Hylobates</i>), which he obtained from strata of the same age +at Saint-Gaudens, in the Haute Garonne. The fossil remains of this +animal consisted of a portion of a lower jaw with teeth and the +shaft of a humerus. It is supposed to have been a tree-climbing +frugivorous ape, equalling man in stature. As the trunks of oaks +are common in the lignite beds in which it lay, it has received the +generic name of <i>Dryopithecus.</i> The angle formed by the +ascending ramus of the jaw and the alveolar border is less open, +and therefore more like the human subject, than in the Chimpanzee, +and what is still more remarkable, the fossil, a young but adult +individual, had all its milk teeth replaced by the second set, +while its last true molar (or wisdom-tooth) was still undeveloped, +or only existed as a germ in the jaw-bone. In the mode, therefore, +of the succession of its teeth (which, as in all the old-World +apes, exactly agree in number with those in man) it differed from +the Gorilla and Chimpanzee, and corresponded with the human +species.</p> + +<p><b>Upper Miocene Beds of Œningen, in +Switzerland.</b>—The faluns of the Loire first served, as +already stated (p. 211), as the type of the Miocene formations in +Europe. They yielded a plentiful harvest of marine fossil shells +and corals, but were entirely barren of plants and insects. In +Switzerland, on the other hand, deposits of the same age have been +discovered, remarkable for their botanical and entomological +treasures. We are indebted to Professor Heer, of Zurich, for the +description, restoration, and classification of several hundred +species and varieties of these fossil plants, the whole of which he +has illustrated by excellent figures in his “Flora Tertiaria +Helvetiæ.” This great work, and those of Adolphe +Brongniart, Unger, Goppert and others, show that this class of +fossils is beginning to play the same important part in the +classification of the tertiary strata containing lignite or brown +coal as an older flora has long played in enabling us to understand +the ancient coal or carboniferous formation. No small skepticism +has always prevailed among botanists as to whether the leaves alone +and the wood of plants could</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 216">[ 216 ]</a></p> + +<p>ever afford sufficient data for determining even genera and +families in the vegetable kingdom. In truth, before such remains +could be rendered available a new science had to be created. It was +necessary to study the outlines, nervation, and microscopic +structure of the leaves, with a degree of care which had never been +called for in the classification of living plants, where the flower +and fruit afforded characters so much more definite and +satisfactory. As geologists, we can not be too grateful to those +who, instead of despairing when so difficult a task was presented +to them, or being discouraged when men of the highest scientific +attainments treated the fossil leaves as worthless, entered with +full faith and enthusiasm into this new and unexplored field. That +they should frequently have fallen into errors was unavoidable, but +it is remarkable, especially if we inquire into the history of +Professor Heer’s researches, how often early conjectures as +to the genus and family founded on the leaves alone were afterwards +confirmed when fuller information was obtained. As examples to be +found on comparing Heer’s earlier and later works, I may +instance the chestnut, elm, maple, cinnamon, magnolia, buckbean or +Menyanthes, vine, buckthorn (<i>Rhamnus</i>), <i>Andromeda</i> and +<i>Myrica,</i> and among the conifers <i>Sequoia</i> and <i> +Taxodium.</i> In all these cases the plants were first recognised +by their leaves, and the accuracy of the determination was +afterwards confirmed when the fruit, and in some instances both +fruit and flower, were found attached to the same stem as the +leaves.</p> + +<p>But let us suppose that no fruit, seed, or flower had ever been +met with in a fossil state, we should still have been indebted to +the persevering labours of botanical palæontologists for one +of the grandest scientific discoveries for which the present +century is remarkable—namely, the proofs now established of +the prevalence of a mild climate and a rich arborescent flora in +the arctic regions in that Miocene epoch on the history of which we +are now entering. It may be useful if I endeavour to give the +reader in a few words some idea of the nature of the evidence of +these important conclusions, to show how far they may be safely +based on fossil leaves alone. When we begin by studying the fossils +of the Newer Pliocene deposits, such as those of the Upper Val +d’Arno, before alluded to, we perceive that the fossil +foliage agrees almost entirely with the trees and shrubs of a +modern European forest. In the plants of the Older Pliocene strata +of the same region we observe a larger proportion of species and +genera which, although they may agree with well-known Asiatic or +other foreign types, are at present</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 217">[ 217 ]</a></p> + +<p>wanting in Italy. If we then examine the Miocene formations of +the same country, exotic forms become more abundant, especially the +palms, whether they belong to the European or American fan-palms, +<i>Chamærops</i> and <i>Sabal</i>, or to the more tropical +family of the date-palms or <i>Phœnicites</i>, which last are +conspicuous in the Lower Miocene beds of Central Europe. Although +we have not found the fruit or flower of these palms in a fossil +state, the leaves are so characteristic that no one doubts the +family to which they belong, or hesitates to accept them as +indications of a warm and sub-tropical climate.</p> + +<p>When the Miocene formations are traced to the northward of the +50th degree of latitude, the fossil palms fail us, but the greater +proportion of the leaves, whether identical with those of existing +European trees or of forms now unknown in Europe, which had +accompanied the Miocene palms, still continue to characterise rocks +of the same age, until we meet with them not only in Iceland, but +in Greenland, in latitude 70° N., and in Spitzbergen, latitude +78° 56', or within about 11 degrees of the pole, and under +circumstances which clearly show them to have been indigenous in +those regions, and not to have been drifted from the south <a href= +"ch15.html#page 240">(see p. 240).</a> Not only, therefore, has the +botanist afforded the geologist much palæontological +assistance in identifying distinct tertiary formations in distant +places by his power of accurately discriminating the forms, +veining, and microscopic structure of leaves or wood, but, +independently of that exact knowledge derivable from the organs of +fructification, we are indebted to him for one of the most novel, +unexpected results of modern scientific inquiry.</p> + +<p>The Miocene formations of Switzerland have been called <i> +Molasse</i>, a term derived from the French <i>mol</i>, and applied +to a <i>soft</i>, incoherent, greenish sandstone, occupying the +country between the Alps and the Jura. This molasse comprises three +divisions, of which the middle one is marine, and being closely +related by its shells to the faluns of Touraine, may be classed as +Upper Miocene. The two others are fresh-water, the upper of which +may be also grouped with the faluns, while the lower must be +referred to the Lower Miocene, as defined in the next chapter.</p> + +<p><b>Upper Fresh-water Molasse.</b>—This formation is best +seen at Œningen, in the valley of the Rhine, between Constance +and Schaffhausen, a locality celebrated for having produced in the +year 1700 the supposed human skeleton called by Scheuchzer +“homo diluvii testis,” a fossil afterwards demonstrated +by Cuvier to be a reptile, or aquatic salamander,</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 218">[ 218 ]</a></p> + +<p>of larger dimensions than even its great living representative, +the salamander of Japan.</p> + +<p>The Œningen strata consist of a series of marls and +limestones, many of them thinly laminated, and which appear to have +slowly accumulated in a lake probably fed by springs holding +carbonate of lime in solution. The elliptical area over which this +fresh-water formation has been traced extends, according to Sir +Roderick Murchison, for a distance of ten miles east and west from +Berlingen, on the right bank of the river to Wangen, and to +Œningen, near Stein, on the left bank. The organic remains +have been chiefly derived from two quarries, the lower of which is +about 550 feet above the level of the Lake of Constance, while the +upper quarry is 150 feet higher. In this last, a section thirty +feet deep displays a great succession of beds, most of them +splitting into slabs and some into very thin laminæ. +Twenty-one beds are enumerated by Professor Heer, the uppermost a +bluish-grey marl seven feet thick, with organic remains, resting on +a limestone with fossil plants, including leaves of poplar, +cinnamon, and pond-weed (<i>Potamogeton</i>), together with some +insects; while in the bed No. 4, below, is a bituminous rock, in +which the <i>Mastodon tapiroides</i>, a characteristic Upper +Miocene quadruped, has been met with. The 5th bed, two or three +inches thick, contains fossil fish, e.g., <i>Leuciscus</i> (roach), +and the larvæ of dragon-flies, with plants such as the elm +(<i>Ulmus</i>), and the aquatic Chara. Below this are other +plant-beds; and then, in No. 9, the stone in which the great +salamander (Andrias Scheuchzeri) and some fish were found. Below +this other strata occur with fish, tortoises, the great salamander +before alluded to, fresh-water mussels, and plants. In No. 16 the +fossil fox of Œningen, <i>Galecynus Œningensis,</i> Owen, +was obtained by Sir R. Murchison. To this succeed other beds with +mammalia (<i>Lagomys</i>), reptiles, (<i>Emys</i>), fish, and +plants, such as walnut, maple, and poplar. In the 19th bed are +numerous fish, insects, and plants, below which are marls of a blue +indigo colour.</p> + +<p>In the lower quarry eleven beds are mentioned, in which, as in +the upper, both land and fresh-water plants and many insects occur. +In the 6th, reckoning from the top, many plants have been obtained, +such as <i>Liquidambar, Daphnogene, Podogonium,</i> and <i> +Ulmus</i>, together with tortoises, besides the bones and teeth of +a ruminant quadruped, named by H. von Meyer <i>Palæomeryx +eminens.</i> No. 9 is called the insect-bed, a layer only a few +inches thick, which, when exposed to the frost, splits into leaves +as thin as paper. In these thin laminæ plants such as <i> +Liquidambar, Daphnogene,</i> and <i>Glyptostrobus</i>,</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 219">[ 219 ]</a></p> + +<p>occur, with innumerable insects in a wonderful state of +preservation, usually found singly. Below this is an indigo-blue +marl, like that at the bottom of the higher quarry, resting on +yellow marl ascertained to be at least thirty feet thick.</p> + +<img src="../images1/fig138.jpg" width="216" height="299" alt= +"Fig. 138: Cinnamomum polymorphum." align="left"> + +<p>All the above fossil-bearing strata were evidently formed with +extreme slowness. Although the fossiliferous beds are, in the +aggregate, no more than a few yards in thickness, and have only +been examined in the small area comprised in the two quarries just +alluded to, they give us an insight into the state of animal and +vegetable life in part of the Upper Miocene period, such as no +other region in the world has elsewhere supplied. In the year 1859, +Professor Heer had already determined no less than 475 species of +plants and more than 800 insects from these Œningen beds. He +supposes that a river entering a lake floated into it some of the +leaves and land insects, together with the carcasses of quadrupeds, +among others a great Mastodon. Occasionally, during tempests, twigs +and even boughs of trees with their leaves were torn off and +carried for some distance so as to reach the lake. Springs, +containing carbonate of lime, seem at some points to have supplied +calcareous matter in solution, giving origin locally to a kind of +travertin, in which organic bodies sinking to the bottom became +hermetically sealed up. The laminæ, says Heer, which +immediately succeed each other were not all formed at the same +season, for it can be shown that, when some of them originated, +certain plants were in flower, whereas, when the next of these +layers was produced, the same plants had ripened their fruit. This +inference is confirmed by independent proofs derived from insects. +The principal insect-bed is rarely two inches thick, and is +composed, says Heer, of about 250 leaf-like laminæ, some of +which were deposited in the spring, when the <i>Cinnamomum +polymorphum</i> (Fig. 138) was in flower, others in summer, when +winged ants were numerous, and when the poplar and willow had +matured their seed; others, again, in autumn, when the same <i> +Cinnamomum polymorphum</i> (Fig. 138) was in fruit, as well as the +liquidambar, oak, clematis,</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 220">[ 220 ]</a></p> + +<p>and many other plants. The ancient lake seems to have had a belt +of poplars and willows round its borders, countless leaves of which +were imbedded in mud, and together with them, at some points, a +species of reed, <i>Arundo</i>, which was very common.</p> + +<p>One of the most characteristic shrubs is a papilionaceous and +leguminous plant of an extinct genus, called by Heer <i> +Podogonium</i>, of which two species are known. Entire twigs have +been found with flowers, and always without leaves, as the flowers +evidently came out, as in the poplar and willow tribe, before any +leaves made their appearance. Other specimens have been obtained +with ripe fruits accompanied by leaves, which resemble those of the +tamarind, to which it was evidently allied, being of the family +Cæsalpineæ, now proper to warmer regions.</p> + +<img src="../images1/fig139.jpg" width="251" height="337" alt= +"Fig. 138: Acer trilobatum." align="left"> + +<p>The Upper Miocene flora of Œningen is peculiarly important, +in consequence of the number of genera of which not merely the +leaves, but, as in the case of the <i>Podogonium</i> just +mentioned, the fruit also and even the flower are known. Thus there +are nineteen species of maple, ten of which have already been found +with fruit. Although in no one region of the globe do so many +maples now flourish, we need not suspect Professor Heer of having +made too many species in this genus when we consider the manner in +which he has dealt with one of them, <i>Acer trilobatum</i>, Figs. +139 and 140. Of this plant the number of marked varieties figured +and named is very great, and no less than three of them had been +considered as distinct species by other botanists, while six of the +others might have laid claim, with nearly equal propriety, to a +like distinction. The common form, called <i>Acer trilobatum</i>, +Fig. 139, may be taken as a normal representative of the +Œningen fossil, and Fig. 140, as one of the most divergent +varieties, having almost four lobes in the leaf instead of +three.</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 221">[ 221 ]</a></p> + +<center><img src="../images1/fig140.jpg" width="285" height="233" alt= +"Fig. 140: Acer trilobatum."></center> + +<p>Among the conspicuous genera which abounded in the Miocene +period in Europe is the plane-tree, <i>Platanus,</i> the fossil +species being considered by Heer to come nearer to the American <i> +P. occidentalis</i> than to <i>P. orientalis</i> of Greece and Asia +Minor. In some of the fossil specimens the male flowers are +preserved. Among other points of resemblance with the living +plane-trees, as we see them in the parks and squares of London, +fossil fragments of the trunk are met with, having pieces of their +bark peeling off.</p> + +<img src="../images1/fig141.jpg" width="166" height="271" alt= +"Platanus aceroides." align="right"> + +<p>The vine of Œningen, <i>Vitis teutonica</i>, Ad. Brong, is +of a North American type. Both the leaves and seeds have been found +at Œningen, and bunches of compressed grapes of the same +species have been met with in the brown coal of Wetteravia in +Germany. No less than eight species of smilax, a monocotyledonous +genus, occur at Œningen and in other Upper Miocene localities, +the flowers of some of them, as well as the leaves, being +preserved; as in the case of the very common fossil, <i>S. +sagittifera</i>, Fig. 142, <i>a.</i></p> + +<p>Leaves of plants supposed to belong to the order Proteaceæ +have been obtained partly from Œningen and partly from the +lacustrine formation of the same age at Locle in the Jura. They +have been referred to the genera <i>Banksia, Grevillea, Hakea,</i> +and <i>Persoonia.</i> Of Hakea there is the impression of a +supposed seed-vessel, with its characteristic thick stalk and +seeds, but as the fruit is without structure, and has not yet</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 222">[ 222 ]</a></p> + +<p>been found attached to the same stem as the leaf, the proof is +incomplete.</p> + +<img src="../images1/fig142.jpg" width="208" height="291" alt= +"Fig. 142: Smilax sagittifera." align="left"> + +<p>To whatever family the foliage hitherto regarded as proteaceous +by many able palæontologists may eventually be shown to +belong, we must be careful not to question their affinity to that +order of plants on those geographical considerations which have +influenced some botanists. The nearest living Proteaceæ now +feel the in Abyssinia in lat. 20° N., but the greatest number +are confined to the Cape and Australia. The ancestors, however, of +the Œningen fossils ought not to be looked for in such distant +regions, but from that European land which in Lower Miocene times +bore trees with similar foliage, and these had doubtless an Eocene +source, for cones admitted by all botanists to be proteaceous have +been met with in one division of that older Tertiary group <a href= +"../images1/fig206.jpg">(see Fig. 206</a>). The source of these last, +again, must not be sought in the antipodes, for in the white chalk +of Aix-la-Chapelle leaves like those of Grevillea and other +proteaceous genera have been found in abundance, and, as we shall +see <a href="ch17.html#page 304">(p. 304)</a> in a most perfect +state of preservation. All geologists agree that the distribution +of the Cretaceous land and sea had scarcely any connection with the +present geography of the globe.</p> + +<center><img src="../images1/fig143.jpg" width="490" height="157" alt= +"Fig. 143: Fruit of the fossil and recent species of Hakea, a genus of Proteaceæ."> +</center> + +<p>In the same beds with the supposed Proteaceæ there occurs +at Locle a fan-palm of the American type Sabal (for genus see Fig. +151), a genus which ranges throughout the low country near the sea +from the Carolinas to Florida and</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 223">[ 223 ]</a></p> + +<p>Louisiana. Among the Coniferæ of Upper Miocene age is +found a deciduous cypress nearly allied to the <i>Taxodium +distichum</i> of North America, and a <i>Glyptostrobus</i> (Fig. +144), very like the Japanese <i>G. heterophyllus,</i> now common in +our shrubberies.</p> + +<img src="../images1/fig144.jpg" width="120" height="214" alt= +"Fig. 144: Glyptostrobus Europæus." align="right"> + +<p>Before the appearance of Heer’s work on the Miocene Flora +of Switzerland, Unger and Goppert had already pointed out the large +proportion of living North American genera which distinguished the +vegetation of the Miocene period in Central Europe. Next in number, +says Heer, to these American forms at Œningen the European +genera preponderate, the Asiatic ranking in the third, the African +in the fourth, and the Australian in the fifth degree. The American +forms are more numerous than in the Italian Pliocene flora, and the +whole vegetation indicates a warmer climate than the Pliocene, +though not so high a temperature as that of the older or Lower +Miocene period.</p> + +<p>The conclusions drawn from the insects are for the most part in +perfect harmony with those derived from the plants, but they have a +somewhat less tropical and less American aspect, the South European +types being more numerous. On the whole, the insect fauna is richer +than that now inhabiting any part of Europe. No less than 844 +species are reckoned by Heer from the Œningen beds alone, the +number of specimens which he has examined being 5080. The entire +list of Swiss species from the Upper and Lower Miocene together +amount to 1322. Almost all the living families of Coleoptera are +represented, but, as we might have anticipated from the +preponderance of arborescent and ligneous plants, the wood-eating +beetles play the most conspicuous part, the Buprestidæ and +other long-horned beetles being particularly abundant.</p> + +<p>The patterns and some remains of the colours both of <i> +Coleoptera</i> and <i>Hemiptera</i> are preserved at Œningen, +as, for example in <i>Harpactor</i> (Fig. 145), in which the +antennæ, one of the eyes, and the legs and wings are +retained. The characters, indeed, of many of the insects are so +well defined as to incline us to believe that if this class of the +invertebrata were not so rare and local, they might be more useful +than even the plants and shells in settling chronological points in +geology.</p> + +<p><b>Middle or Marine Molasse (Upper Miocene) of +Switzerland.</b>—It was before stated that the Miocene +formation of Switzerland</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 224">[ 224 ]</a></p> + +<img src="../images1/fig145.jpg" width="172" height="284" alt= +"Fig. 145: Harpactor maculipes." align="left"> + +<p>consisted of, first, the upper fresh-water molasse, comprising +the lacustrine marls of Œningen; secondly, the marine molasse, +corresponding in age to the faluns of Touraine; and thirdly, the +lower fresh-water molasse. Some of the beds of the marine or middle +series reach a height of 2470 feet above the sea. A large number of +the shells are common to the faluns of Touraine, the Vienna basin, +and other Upper Miocene localities. The terrestrial plants play a +subordinate part in the fossiliferous beds, yet more than ninety of +them are enumerated by Heer as belonging to this falunian division, +and of these more than half are common to subjacent Lower Miocene +beds, while a proportion of about forty-five in one hundred are +common to the overlying Œningen flora. Twenty-six of the +ninety-two species are peculiar.</p> + +<img src="../images1/fig146.jpg" width="119" height="174" alt= +"Fig. 146: Olica Dufresnii." align="right"> + +<p><b>Upper Miocene of the Bolderberg, in Belgium.</b>—In a +small hill or ridge called the Bolderberg, which I visited in 1851, +situated near Hasselt, about forty miles E.N.E. of Brussels, strata +of sand and gravel occur, to which M. Dumont first called attention +as appearing to constitute a northern representative of the faluns +of Touraine. On the whole, they are very distinct in their fossils +from the two upper divisions of the Antwerp Crag before mentioned +<a href="ch13.html#page 204">(p. 204)</a>, and contain shells of +the genera <i>Oliva, Conus, Ancillaria, Pleurotoma,</i> and <i> +Cancellaria</i> in abundance. The most common shell is an Olive +(Fig. 146), called by Nyst <i>Oliva Dufresnii</i>; and +constituting, as M. Bosquet observes, a smaller and shorter variety +of the Bordeaux species.</p> + +<p>So far as the shells of the Bolderberg are known, the proportion +of recent species agrees with that in the faluns of Touraine, and +the climate must have been warmer than that of the Coralline Crag +of England.</p> + +<p><b>Upper Miocene Beds of the Vienna Basin.</b>—In South +Germany the general resemblance of the shells of the Vienna +tertiary basin with those of the faluns of Touraine has long been +acknowledged. In the late Dr. Hörnes’s excellent +work</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 225">[ 225 ]</a></p> + +<p>on the fossil mollusca of that formation, we see accurate +figures of many shells, clearly of the same species as those found +in the falunian sands of Touraine.</p> + +<p>According to Professor Suess, the most ancient and purely marine +of the Miocene strata in this basin consist of sands, +conglomerates, limestones, and clays, and they are inclined inward, +or from the borders of the trough towards the centre, their +outcropping edges rising much higher than the newer beds, whether +Miocene or Pliocene, which overlie them, and which occupy a smaller +area at an inferior elevation above the sea. M. Hornes has +described no less than 500 species of gasteropods, of which he +identifies one-fifth with living species of the Mediterranean, +Indian, or African seas, but the proportion of existing species +among the lamellibranchiate bivalves exceeds this average. Among +many univalves agreeing with those of Africa on the eastern side of +the Atlantic are <i>Cypræa sanguinolenta, Buccinum +lyratum,</i> and <i>Oliva flammulata.</i> In the lowest marine beds +of the Vienna basin the remains of several mammalia have been +found, and among them a species of <i>Dinotherium</i>, a Mastodon +of the <i>Trilophodon</i> family, a Rhinoceros (allied to <i>R. +megarhinus</i>, Christol), also an animal of the hog tribe, <i> +Listriodon</i>, von Meyer, and a carnivorous animal of the canine +family. The <i>Helix turonensis</i> <a href="../images/fig38.jpg"> +(Fig. 38)</a>, the most common land shell of the French faluns, +accompanies the above land animals. In a higher member of the +Vienna Miocene series are found <i>Dinotherium giganteum</i> <a +href="../images1/fig136.jpg">(Fig. 136)</a>, <i>Mastodon longirostris, +Rhinoceros Schleiermacheri, Acerotherium incisivum,</i> and <i> +Hippotherium gracile,</i> all of them equally characteristic of an +Upper Miocene deposit occurring at Eppelsheim, in Hesse Darmstadt; +a locality also remarkable as having furnished in latitude 49° +50' N. the bone of a large ape of the Gibbon kind, the most +northerly example yet discovered of a quadrumanous animal.</p> + +<img src="../images1/fig147.jpg" width="130" height="164" alt= +"Fig. 147: Amphistegina Hauerina." align="right"> + +<p>M. Alcide d’Orbigny has shown that the foraminifera of the +Vienna basin differ alike from the Eocene and Pliocene species, and +agree with those of the faluns, so far as the latter are known. +Among the Vienna foraminifera, the genus <i>Amphistegina</i> (Fig. +147) is very characteristic, and is supposed by d’Archiac to +take the same place among the Rhizopods of the Upper Miocene era +which the Nummulites occupy in the Eocene period.</p> + +<p>The flora of the Vienna basin exhibits some species which</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 226">[ 226 ]</a></p> + +<p>have a general range through the whole Miocene period, such as +<i>Cinnamomum polymorphum</i> <a href="../images1/fig138.jpg">(Fig. +138)</a>, and <i>C. Scheuchzeri,</i> also Planera Richardi, Mich., +<i>Liquidambar europæum</i> <a href="../images1/fig134.jpg"> +(Fig. 135)</a> <i>Juglans bilinica, Cassia ambigua,</i> and <i>C. +lignitum.</i> Among the plants common to the Upper Miocene beds of +Œningen, in Switzerland, are <i>Platanus aceroides</i> <a +href="../images1/fig141.jpg">(Fig. 141)</a>, <i>Myrica +vindobonensis,</i> and others.</p> + +<p><b>Upper Miocene Strata of Italy.</b>—We are indebted to +Signor Michelotti for a valuable work on the Miocene shells of +Northern Italy. Those found in the hill called the Superga, near +Turin, have long been known to correspond in age with the faluns of +Touraine, and they contain so many species common to the Upper +Miocene strata of Bordeaux as to lead to the conclusion that there +was a free communication between the northern part of the +Mediterranean and the Bay of Biscay in the Upper Miocene +period.</p> + +<p><b>Upper Miocene Formations of Greece.</b>—At +Pikermé, near Athens, MM. Wagner and Roth have described a +deposit in which they found the remains of the genera <i>Mastodon, +Dinotherium, Hipparion,</i> two species of <i>Giraffe, +Antelope,</i> and others, some living and some extinct. With them +were also associated fossil bones of the <i>Semnopithecus,</i> +showing that here, as in the south of France, the quadrumana were +characteristic of this period. The whole fauna attests the former +extension of a vast expanse of grassy plains where we have now the +broken and mountainous country of Greece; plains, which were +probably united with Asia Minor, spreading over the area where the +deep Ægean Sea and its numerous islands are now situated. We +are indebted to M. Gaudry, who visited Pikermé, for a +treatise on these fossil bones, showing how many data they +contribute to the theory of a transition from the mammalia of the +Upper Miocene through the Pliocene and Post-pliocene forms to those +of living genera and species.</p> + +<p><b>Upper Miocene of India. Siwâlik Hills.</b>—The +Siwâlik Hills lie at the southern foot of the Himalayan +chain, rising to the height of 2000 and 3000 feet. Between the +Jumna and the Ganges they consist of inclined strata of sandstone, +shingle, clay, and marl. We are indebted to the indefatigable +researches of Dr. Falconer and Sir Proby Cautley, continued for +fifteen years, for the discovery in these marls and sandstones of a +great variety of fossil mammalia and reptiles, together with many +fresh-water shells. Out of fifteen species of shells of the genera +<i>Paludina, Melania, Ampullaria,</i> and <i>Unio,</i> all are +extinct or unknown species with the exception of four, which are +still inhabitants of Indian rivers. Such a</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 227">[ 227 ]</a></p> + +<p>proportion of living to extinct mollusca agrees well with the +usual character of an Upper Miocene or Falunian fauna, as observed +in Touraine, or in the basin of Vienna and elsewhere.</p> + +<p>The genera of mammalia point in the same direction. One of them, +of the genus <i>Chalicotherium</i> (or <i>Anisodon</i> of Lartet), +is a pachyderm intermediate between the <i>Rhinoceros</i> and <i> +Anoplothere,</i> and characteristic of the Upper Miocene strata of +Eppelsheim, and of the south of France. With it occurs also an +extinct form of Hippopotamus, called Hexaprotodon, and a species of +Hippotherium and pig, also two species of <i>Mastodon</i>, two of +elephant, and three other elephantine proboscidians; none of them +agreeing with any fossil forms of Europe, and being intermediate +between the genera Elephas and Mastodon, constituting the sub-genus +<i>Stegodon</i> of Falconer. With these are associated a monkey, +allied to the <i>Semnopithecus entellus</i>, now living in the +Himalaya, and many ruminants. Among these last, besides the +giraffe, camel, antelope, stag, and others, we find a remarkable +new type, the <i>Sivatherium,</i> like a gigantic four-horned deer. +There are also new forms of carnivora, both feline and canine, the +<i>Machairodus</i> among the former, also hyænas, and a +subursine form called the Hyænarctos, and a genus allied to +the otter (<i>Enhydriodon</i>), of formidable size.</p> + +<p>The giraffe, camel, and a large ostrich may be cited as proofs +that there were formerly extensive plains where now a steep chain +of hills, with deep ravines, runs for many hundred miles east and +west. Among the accompanying reptiles are several crocodiles, some +of huge dimensions, and one not distinguishable, says Dr. Falconer, +from a species now living in the Ganges (<i>C. Gangeticus</i>); and +there is still another saurian which the same anatomist has +identified with a species now inhabiting India. There was also an +extinct species of tortoise of gigantic proportions +(<i>Colossochelys Atlas</i>), the curved shell of which was twelve +feet three inches long and eight feet in diameter, the entire +length of the animal being estimated at eighteen feet, and its +probable height seven feet.</p> + +<p>Numerous fossils of the Siwâlik type have also been found +in Perim Island, in the Gulf of Cambay, and among these a species +of <i>Dinotherium,</i> a genus so characteristic of the Upper +Miocene period in Europe.</p> + +<p><b>Older Pliocene and Miocene Formations in the United +States.</b>—Between the Alleghany Mountains, formed of older +rocks, and the Atlantic, there intervenes, in the United States, a +low region occupied principally by beds of marl, clay, and sand, +consisting of the cretaceous and tertiary formations,</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 228">[ 228 ]</a></p> + +<p>and chiefly of the latter. The general elevation of this plain +bordering the Atlantic does not exceed 100 feet, although it is +sometimes several hundred feet high. Its width in the middle and +southern states is very commonly from 100 to 150 miles. It +consists, in the South, as in Georgia, Alabama, and South Carolina, +almost exclusively of Eocene deposits; but in North Carolina, +Maryland, Virginia, Delaware, more modern strata predominate, of +the age of the English Crag and faluns of Touraine.*</p> + +<center><img src="../images1/fig148.jpg" width="399" height="221" alt= +"Fig. 148: Fulgur canaliculatus. Fig. 149: Fusus quadricostatus."> +</center> + +<p>In the Virginian sands, we find in great abundance a species of +Astarte (<i>A. undulata,</i> Conrad), which resembles closely, and +may possibly be a variety of, one of the commonest fossils of the +Suffolk Crag (<i>A. Omalii</i>); the other shells also, of the +genera <i>Natica, Fissurella, Artemis, Lucina, Chama, +Pectunculus,</i> and <i>Pecten,</i> are analagous to shells both of +the English Crag and French faluns, although the species are almost +all distinct. Out of 147 of these American fossils I could only +find thirteen species common to Europe, and these occur partly in +the Suffolk Crag, and partly in the faluns of Touraine; but it is +an important characteristic of the American group, that it not only +contains many peculiar extinct forms, such as <i>Fusus +quadricostatus,</i> Say (see Fig. 149), and <i>Venus +tridacnoides,</i> abundant in these same formations, but also some +shells which, like <i>Fulgur carica</i> of Say and <i>F. +canaliculatus</i> (see Fig. 148), <i>Calyptræa costata, Venus +mercenaria,</i> Lam., <i>Modiola glandula,</i> Totten, and <i> +Pecten magellanicus,</i> Lam., are recent species, yet of forms now +confined to the western side of the Atlantic—a fact implying +that some traces of the beginning of the present geographical +distribution of mollusca</p> + +<p class="fnote">* Proceedings of the Geol. Soc., vol. iv, pt. iii, +1845, p. 547.</p> + +<p> </p> + +<hr> +<p class="page"><a name="page 229">[ 229 ]</a></p> + +<p>date back to a period as remote as that of the Miocene +strata.</p> + +<img src="../images1/fig150.jpg" width="152" height="184" alt= +"Fig. 150: Astrangia lineata." align="right"> + +<p>Of ten species of corals which I procured on the banks of the +James River, one agrees generically with a coral now living on the +coast of the United States. Mr. Lonsdale regarded these corals as +indicating a temperature exceeding that of the Mediterranean, and +the shells would lead to similar conclusions. Those occurring on +the James River are in the 37th degree of N. latitude, while the +French faluns are in the 47th; yet the forms of the American +fossils would scarcely imply so warm a climate as must have +prevailed in France when the Miocene strata of Touraine +originated.</p> + +<p>Among the remains of fish in these post-eocene strata of the +United States are several large teeth of the shark family, not +distinguishable specifically from fossils of the faluns of +Touraine.</p> + +<br> +<hr> +<small><a href="contents.html">Contents</a> / <a href="ch13.html"> +Chapter XIII</a> / <a href="ch15.html">Chapter XV</a></small> +</body> +</html> + |