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fissures which are filled with matters wholly foreign to their constitution. These veins are allowed by all to be of posterior formation to the masses between which they are interposed. Sometimes veins of different substances cut through each other, and in this case it is obvious that the one which is cut must have been of older formation than the one which traverses it. The disorder and various degrees of inclination of the planes of the strata point to some great revolution which must have broken their surfaces by the elevation of the upper or the depression of the lower ridge. Geologists all agree in this unavoidable inference, though they differ from each other as to the nature of the cause. In the science of geology, of late, observation has certainly greatly superseded useless speculation, and the classification of the different formations of the earth's surface, the distinction and description of different individuals of a series, the analysis of minerals, and the investigation of their properties, have taken the place of useless cavils about remoter causes. It is by such gradual means that we may hope to penetrate the secrets ..of time; step by o to unravel the long series of past events; to harmonise philosophy with history. There is not a more interesting or important department of this science than that which involves the consideration of organic remains; varying as much in regard to the state in which they are found as in their respective species. Sometimes the most delicate bodies are little changed by the processes which they have undergone; sometimes they are completely impregnated with stony matter; and often exhibit mere casts of the original substance. Uniting perhaps in himself more extensive knowledge of every department of nature than any other existing individual, it has been the arduous undertaking of M. Cuvier not only to class the different species, and compare them with their existing analogues, but carefully to ascertain the superpositions of the strata in which their remains occur, and their connexion with the different animals and plants which they enclose. He has particularly illustrated the fossil remains of quadrupeds; and the highest degree of importance attaches to this class of fossils. They indicate more clearly than others the nature of the revolutions they have undergone. The important fact of the repeated irruptions of the sea upon the land is by them placed beyond a doubt. The remains of shells and of other bodies of marine origin might merely indicate that the sea had once existed where these collections are found. Thousands of aquatic animals may have been left dry by a recess of the waves, while their races may have been preserved in more peaceful parts of the ocean. But a change in the bed of the sea, and a general irruption of its waters, must have destroyed all the quadrupeds within the reach of its influence. Thus entire classes of animals, or at least many species, must have been utterly destroyed. Whether this actually has been the case we are more easily able to determine from the greater precision of our knowledge with respect to the quadrupeds, and the smaller limits of their number. It may be decided at Vol. XVIII.

once whether fossil bones belong to any species which still exists, or to one that is lost; but it is impossible to say whether fossil testaceous animals, although unknown to the zoologist, may not belong to genera yet undiscovered in the fathomless depths of the sea. This indefatigable observer of nature, from a mature consideration of the subject, after a display of the most complete knowledge of the osteology of comparative anatomy, and after a learned comparison of the description of the rare animals of the ancients, and the fabulous products of their imaginations, draws the following instructive conclusion :-‘None of the larger . species of quadrupeds, whose remains are now found imbedded in regular rocky strata, are at all similar to any of the known living species. This circumstance is by no means the mere effect of chance, or because the species to which these fossil bones have belonged are still concealed in the desert and uninhabited parts of the world, and have hitherto escaped the observation of travellers, but this astonishing phenomenon has proceeded from general causes, and the careful investigation of it affords one of the best means for discovering and investigating the nature of those causes.’ The method of observation adopted is susceptible, he contends, of the utmost accuracy. “Every organised individual forms an entire system of its own, all the parts of which mutually correspond and concur to produce a certain definite purpose by reciprocal re-action, or by combining towards the same end. Hence none of these separate parts can change their forms without a corresponding change on the other parts of the same animal, and consequently each of these parts taken separately indicates all the other parts to which it has belonged. Thus, if the viscera of an animal are so organised as only to be fitted for the digestion of recent flesh, it is also requisite that the jaws should be so constructed as to fit them for devouring their prey; the claws must be constructed for seizing and tearing it to pieces; the teeth for cutting and dividing its flesh; the entire system of the limbs, or organs of motion, for pursuing and overtaking it; and the organs of sense for discovering it at a distance. Hence any one who observes merely the print of a cloven foot, may conclude that it has been left by a ruminant animal; and regard the conclusion as equally certain with any other in physics or in morals. Consequently, this single foot-mark clearly indicates to the observer the forms of the teeth, of the jaws, of the vertebræ, of all the leg bones, thighs, shoulders, and of the trunk of the body of the animal that left the mark.’ It is from this connexion of all the different parts of an animal that the smallest piece of bone may become the sure index of the class and species of the animal to which it has belonged; and it is from an indefatigable and ingenious application of this rule that our author has been enabled to class the fossil remains of seventyeight different quadrupeds, of which forty-nine are distinct species, hitherto unknown to naturalists. The bones are generally dispersed, seldom occurring in complete skeletons, and 2 I

still more rarely is the fleshy part of the animal preserved. But one of the most important and interesting of the observations for which we are indebted to the precision of the French naturalist is the distinction of two different formations amongst secondary strata. These consist of alternate deposits from salt and fresh water; and are characterised by the nature of the shells which are found imbedded in them. The country about Paris is founded upon chalk. This is covered with clay and a coarse limestone, containing marine petrifactions. Over this lies an alternating series of gypsum and clay, in which occur the remains of quadrupeds, birds, fish, and shells, all of land or fresh water species. Above this interesting stratum lie marl and sandstone, containing marine shells, which are covered with beds of limestone and flint, which again contain petrifactions of fresh water remains. The upper bed of all is of an alluvial nature, in which trunks of trees, bones of elephants, oxen, and rein-deer, intermingled with salt water productions, seem to suggest that both salt and fresh water have contributed to its accumulation. This alternate flux and reflux of the two fluids is a most extraordinary phenomenon, and promises to lead to an important conclusion respecting the general theory of the earth. We are inclined to think that something analogous to the process which produced these changes may be perceived in operations which are going on in our own time, and in gradual alterations which have been effected within the memory of one generation. The following extract from the accurate descriptions of the indefatigable De Luc will better explain our ideas. We have selected one from among many instances which are afforded by an attentive examination of our own coasts. ‘Slapton Lee occupies the lower part of a combe, which at first formed a recess in the bay, but, the sea before it being shallow, the waves brought up the gravel from the bottom along the coast, and the beach thus produced passed at length quite across this recess, which it closed: since then, the fresh water proceeding from the combe has almost entirely displaced the salt water within this space, because the former arriving there freely, and passing through the gravel of the beach, repels the small quantity of the sea water which filtrates into it. Slapton Lee, which is about two miles in length and a quarter of a mile in its greatest breadth, is a little brackish, on account of its communications with the sea water, as well through the gravel in common seasons, as when there is any opening in the beach; however, it contains fresh water fish, carp, tench, and pike. The sediments of the land waters are tending to fill up this basis, and wherever the bottom is sufficiently raised the reeds are beginning to grow.’ Such may have been the process which formed a fresh water deposit upon a marine basis. By extending the analogy further, we can have little difficulty in conceiving that the barrier thus raised by the action of the waves may have been easily destroyed again, even by an extraordinary exertion of the same power which raised it, or by some other of those violent revolutions whose

effects are marked upon the face of the whole earth. Thus a way was opened for the return of the waters of the ocean, which again deposited their sediments and the remains of their living tribes, and thus gave rise to the upper salt water strata. The same causes again acting excluded once more the waves of the sea, and gave time for the deposit of the upper fresh water formation. . Such an explanation appears to us simple and satisfactory. It accounts for the phenomena of nature by nature's laws. But, however this may be, the sagacity which first pointed out the distinction cannot be too much praised. The discovery has already stimulated the exertions of others, and there is reason to suppose that the phenomenon is not only not confined to the environs of Paris, but is of pretty general occurrence in secondary countries. A similar formation has been observed in the Isle of Wight; and has been most scientifically described and compared with the French strata by a member of the Geological Society. It is remarkable that those coarse limestone strata which are chiefly employed at Paris for building, are the last formed series which indicate a long and quiet continuance of the water of the sea above the surface of the continent. About them indeed there are found formations containing abundance of shells and other productions of the sea, but these consist of alluvial materials, sand, marle, sand-stone, or clay, which rather indicate transportations that have taken place with some degree of violence than strata formed by quiet depositions; and, where some regular rocky strata of inconsiderable extent and thickness appear above or below these alluvial formations, they generally bear the marks of having been deposited from fresh water. All the known specimens of the bones of viviparous land quadrupeds have either been found in these formations from fresh water, or in the alluvial formations; whence there is every reason to conclude that these animals have only begun to exist, or at least to leave their remains in the strata of our earth since that retreat of the sea which was next before its last irruption. It has also been clearly ascertained, from an attentive consideration of the relation of the different remains with the strata in which they have been discovered, that oviparous quadrupeds are found in much older strata than those of the viviparous class. Some of the former have been observed in and even beneath the chalk. Dry land and fresh waters must therefore have existed before the foundation of the chalk strata. No bones of mammiferous quadrupeds are to be found till we come to the newer formations, which lie over the coarse limestone strata incumbent on the chalk. Determinate order may also be observed in the succession of these. The genera which are now unknown are the lowest in position: unknown species of known genera are next in succession; and lastly, the bones of species, apparently the same with those which are now in existence, are never found but in the latest alluvial depositions. The more we learn respecting the secondary strata of the globe, the more interesting becomes the investigation. The bold outline of the primitive ranges, their cloud-capt summits and majestic forms, are calculated to rivet the attention; but they rather force the fancy to speculate upon their formation than lead the judgment by internal evidences to their origin. It is in the curious observations above recited that we seem to approach the history of our own state. The study of secondary formations is as yet scarcely commenced. The labors of Cuvier have thrown a new light upon their high importance; already by his exertions has the history of the most recent changes been ascertained, in one articular spot, as far as the chalk formation. is, which has hitherto been conceived to be of very modern origin, is shown to have owed its deposition to causes connected with the revolution and catastrophe before the last general irruption of the waters over our present habitable world. Our author well observes that these posterior geological facts, which have hitherto been neglected by geologists, furnish the only clue by which we may hope, in some measure, to dispel the darkness of the preceding times. “It would certainly be exceedingly satisfactory to have the fossil organic productions arranged in chronological order, in the same manner as we now have the principal mineral substances. By this the science of organization itself would be improved; the development of animal life; the succession of its forms; the precise determinations of those which have been first called into existence, the simultaneous production of certain species and their gradual extinction;–all these would perhaps instruct us fully as much in the essence of organisation as all the experiments that we shall ever be able to make upon living animals: and man, to whom only a short space of time is allotted upon the earth, would have the glory of restoring the history of thousands of ages which preceded the existence of the race, and of thousands of animals which never were contemporaneous with his species.’ In the present state of science respecting them we cannot, we conceive, assist the geological student better than by presenting to him an ample classification of existing organic remains. We depend in the first instance largely on the abstract of Cuvier's researches furnished in the notes of Mr. Jameson to M. Kerr's translation of the Essay on the Earth.

CLASS I.-MAMMALIA. Order I.-DIGITATA. Family.—Glires. Cavia.-The slaty limestone of Oeningen, near Schaffhausen, affords remains of a species of this genus. Cuvier conjectures it to belong to the cavia porcellus or Guinea pig, or more likely to an unknown species of this tribe, or of that entitled arvicola. Mus, mouse.—In the slaty limestone rocks at Walsch, in the circle of Saatz, Bohemia, there are fossil remains of a species of this tribe nearly allied to the mus terrestris; smaller remains occur in alluvial strata at Kostritz, in Germany, and in the limestone of Corsica. Lagomys. Occurs in fissures of the third se.

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Ursus, bear.—2. U. Spelaeus.-The size of a horse, and different from any of the present existing species. 2. U. Arctoideus.—A smaller species, also extinct. Both species are fossil, and remains of them are found in great abundance in limestone caves in Germany and Hungary. The caves vary much in magnitude and form, and are more or less deeply incrusted with calcareous sinter, which assumes a great variety of singular and often beautiful forms. The bones occur nearly in the same state in all these caves: detached, broken, but never rolled; they are somewhat lighter and less compact than recent bones, but slightly decomposed, contain much gelatine, and are never mineralised. They are generally enveloped in an indurated earth, which contains animal matter; sometimes in a kind of alabaster or calcareous sinter, and by means of this mineral are sometimes attached to the walls of the caves. It is worthy of remark that these bones occur in an extent of upwards of 200 leagues.

Cuvier thinks that rather more than threefourths of the bones in the caves of Gaylenreuth, Bavaria, belong to species of bears now extinct; one-half, or two-thirds of the remaining fourth belong to a species of hyaena, which oc. curs in a fossil state in other situations. A very small number of these remains belong to a species of the genus lion or tiger; and another to animals of the dog or wolf kinds; and, lastly, the smallest portion belongs to different species of smaller carnivorous animals, as the fox and pole-cat. Cuvier is inclined to conjecture that the animals to which they belonged must have lived and died peaceably on the spot where we now find them. This opinion is rendered highly probable from the nature of the earthy matter in which they are enveloped, and which, according to Laugier, contains an intermixture of animal matter with phosphate of lime, and probably also phosphate of iron. Remains of the fossil bear also occur in limestone caves in England.

Canis, hyana, and wolf—Several species occur in the caves already mentioned; one very closely resembles the Cape hyaena, and is about the size of a small brown bear; another species is allied to the dog or wolf; and a third species is almost identical with the common fox. A fossil species also resembling the common fox has been found in the gypsum quarries near Paris; and in the same formation there are fossil remains of a genus intermediate between canis and viverra. Remains of the wolf were found at Cannstadt in Germany, along with those of the elephant, rhinoceros, hyaena, horse, deer, and hare. In the alluvial deposites there are remains of the hyaena. Blumenbach has described the remains of a fossil hyaena, nearly resembling

the canis crocuta, which was found in marlalong with the remains of the lion and the elephant, between Osterode and Herzberg in Hanover. Professor Buckland's account of the Kirkdale cave of hyaenas will be found in our article GREAT BRITAIN, vol. x. p. 596.

Bones of hyaenas have been found in similar caves in other parts of Great Britain, viz. at Crawly Rocks near Swansea, in the Mendip Hills at Clifton, at Wirksworth in Derbyshire, and at Oreston, near Plymouth. In some of these there is evidence of the bones having been introduced by beasts of prey; but in that of Hutton Hill, in the Mendips, which contains rolled stones, it is probable they were washed in.

Felis, tiger.—One species occurs in the limestone caves of Germany, and appears to be nearly allied to the jaguar; another species, nearly allied to the tiger, is found in alluvial soil along with fossil remains of the elephant, rhinoceros, hyaena, and mastodon.

Viverra, weasel.—Two species occur in the German limestone caves; the one is allied to the common pole-cat, and the other to the zorille, a pole-cat belonging to the cape of Good Hope. Another species allied to the ichneumon, but double its size, occurs in the gypsum quarries around Paris.

Family.—Bruta.

Bradypus, sloth-Two fossil species have been described, which are nearly allied not only to the two living species, but also to the myrmecophaga, orant eater. They are the following:— 1. Megalonix.-This remarkable fossil animal appears to have been the size of an ox. Its remains were first discovered in limestone caves in Virginia in the year 1796. 2. Megatherium. —This species is the size of the rhinoceros, and its fossil remains have hitherto been found only in South America. The first, and most complete skeleton, was sent from Buenos Ayres by the marquis Loretto, in the year 1789. It was found in digging an alluvial soil, on the banks of the river Luxan, a league south-east of the village of that name, about three leagues W. S. W. of Buenos Ayres. Plate I. fig. 1, REMAINS, ORGAN1c, gives a faithful representation of this remarkable skeleton, which is now preserved in the Royal Cabinet of Madrid. A second skeleton of the same animal was sent to Madrid from Lima, in the year 1795; and a third was found in Paraguay. Thus it appears that the remains of this animal exist in the most distant parts of South America. It is very closely allied to the megalonix, and differs from it principally in size, being much larger. Cuvier is of opinion that the two species, the megalonix and megatherium, may be placed together, as members of the same genus, and should be placed between the sloths and ant-eaters, but nearer to the former than to the latter. It is worthy of remark that the remains of these animals have not been hitherto found in any other quarter of the globe besides America, the only existing country which affords them.

Order II.-MARSUPIALIA.

Didelphis, opossum.—One species of this exuraordinary tribe has been found in a fossil state in the gypsum quarries near Paris. It does not

belong to any of the present existing species, and is therefore considered as extinct. Cuvier remarks that, as all the species of this genus are natives of America, it is evident that the hypothesis advanced by some naturalists, of all the fossil organic remains of quadrupeds baving been flooded from Asia to northern countries, is erroneous.

Order III.-SolipUNGula.

Equus adamaticus, equus caballus *—Fossil teeth of a species of horse are found in alluvial soils associated with those of the elephant, rhinoceros, hyaena, mastodon, and tiger? These teeth are larger than those of the present horse, and to all appearance belong to a different species which inhabited the countries where they are now found, as Great Britain, along with elephants, rhinoceroses, &c.

Order IV.-BisulcA. Cervus, deer.—1. Fossil elk of Ireland.—This, the most celebrated of all the fossil ruminating animals, is certainly of a different species from any of those that at present live on the earth's surface, and may therefore be considered as extinct. It was first found in Ireland, where it generally occurs in shell marl and in peat-bogs. It has also been found in superficial alluvial soil in England, Germany, and France. In plate I. fig. 2, we have given a drawing of the head and horns of this animal. It was dur out of a marl pit at Dardisdoun, near Drogheda, in Ireland. Dr. Molyneux, in the Philosophical Transactions, informs us that its dimensions were as follows:—

Ft. In. From the extreme tip of each horn . - • - . a. b. 10 10 From the tip of the right horn to its root . - - . c. d. 5 2 From the tip of one of the inner branches to the tip of the opposite branch - . e. f. 3 75 The length of one of the palms, within the branches . . g. h. 2 6 The breadth of the palm, within the branches - - ... i. k. 1 10} The length of the right brow antler . - - - - d. l. 1 2 The beam of each horn at some distance from the head, in diameter . - - . Ill. 0 2/3 in circumference, . 0 8 The beam of each horn, at its root, in circumference . . d. 0 11 The length of the head, from the back of the skull to the extremity of the upper jaw, n. o. 2 0 Breadth of the skull . p. Q. 1 0

We saw a fine specimen of the horns of this animal in the summer of 1828 at Knole, the seat of the duke of Dorset. It is exalted among the trophies of the chase in the hall of his grace, but not claiming we suppose to have been hunted by a duke of Dorset. A splendid and nearly perfect skeleton of this animal has been lately dug out of a marl pit in the Isle of Man, and is now preserved in the Regium Museum of Edinburgh.

2. Fossil deer of Scania.—Found in a peat

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