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various philosophical pursuits—an impulse proportioned to the novelty and magnitude of those discoveries, and the wide range of sciences with which they are connected. When a comparison is instituted between what now is and what has been, whether with reference to the works of external nature or the history of mankind, the desire of explaining what is obscure in the past supplies an additional motive to examine a multitude of facts, within the reach of our actual observation, with more minute accuracy, and to generalize them with more comprehensive views. Geology is continually concerned in such comparisons; by prompting us to investigate in more detail both the animate and inanimate kingdoms of nature, it has enlarged these departments of study and revealed a multitude of new phemomena connected with them; but it has done more than this: it has elevated their rank and dignity, by teaching us the laws of the aggregation and distribution of simple minerals, and by requiring more comprehensive systems for the arrangement of the animal and vegetable productions of the earth. This latter branch of science has engaged the energies of many powerful minds from the days of Linnaeus to our own times; M. Cuvier, in his preface to the ‘Régne Animal, justly remarks that ‘the habit necessarily derived from the study of natural history, of classing in the mind a great number of ideas, is one of the advantages of this science, the least talked of, but which may rank perhaps as the principal when it shall have been generally introduced into ordinary education.” In addition to these advantages, derived from the study of natural history, geology has the merit of exerting continually the reasoning faculties in deducing conclusions from numerous data and complicated phenomena; and although it cannot appeal to demonstrative proof, it may often conduct us to moral certainty. It is constantly concerned in weighing a great mass of probable evidence, and is therefore powerfully instrumental in exercising the mind and strengthening the judgment. It is now our intention to take a rapid view of some of the principal accessions to our knowledge derived from the geological investigations of the few last years; but we shall chiefly confine ourselves for the present to the consideration of Fossil Organic Remains. We are aware that other branches of geology, intimately connected with chemistry, and exerting a more decided influence on the general process of physical science, may lay claim to higher rank, but we select a department abounding in recent and splendid discoveries, and which has till very lately been treated with unaccountable neglect. We shall have occasion to advert to most of the memoirs in the volume before us, us, but we shall treat of them only when they happen to throw light on the chief subject-matter of this Article. When controverted questions of interest present themselves, or generally received opinions chance to clash with our own, we shall discuss their merits without staying to inquire how far our digressions may sometimes be inconsistent with the Horatian maxim, ‘sit quodvis simplex duntaxat et unum.' A very limited number of Mammiferous quadrupeds are natives of the British islands, or have inhabited them since we have any traditionary information. If we include the Bear, Wolf, and Beaver, now exterminated, and the Fallow Deer, which is supposed not to be indigenous, they may be comprised within twenty-three genera. But we have now discovered that this part of the earth was once peopled by many other animals of the same class. The horns of the Scandinavian,” and almost entire skeletons of the Irish elk, (the latter a species now unknown throughout the globe,) have been found buried in peat and marl, evidently of origin posterior to the last extensive revolution which modified the surface of the land. Besides these, in superficial loam and gravel, consisting of transported materials, and in caves and fissures of rocks, the remains of species belonging to at least fifteen distinct genera occur; some of them identical with those still surviving in England, others being extinct species. Of these last, the remains of the Elephant, Rhinoceros, and Hippopotamus are very extensively distributed. Those of the Cave-bear and Cave-hyaena have been found in but a very few spots; but the bones of the hyaena already obtained must have belonged to several hundred individuals. Remains of a Tiger and two species of Deer have been also found, but too inconsiderable in number to enable us at present to decide on their specific characters. In similar geological situations in other parts of Europe, where the existing viviparous quadrupeds do not greatly out-number those of England, there are found in company with the fossils above enumerated a species of mastodon, (a lost genus that bore some affinity to the elephant,) a small hippopotamus, three species of rhinoceros, a gigantic tapir, a camel, F and several others. But we have not yet penetrated beyond the first boundaries of this new region of discovery. Even since the very recent publication of the third edition of M. Cuvier's Fossil Osteology, in which all the above were described, no less than thirty species of animals have been found in volcanic tufa in the department of Puy-de-Dôme in France,” principally in Mount Perrier near the Issoire, and a large proportion of these prove to be extinct and hitherto unknown quadrupeds. Among them are an Elephant, a small Mastodon, a Rhinoceros, Hippopotamus, small Tapir, many of the genus Cervus, two Bears, three Panthers, an Hyaena, a Fox, and an Otter. We shall not at present extend our views to North America, a field rich in the same class of fossil remains, belonging chiefly (like those in the alluvial deposits of Europe) to existing genera, and also to such as are in a great degree confined at present to equinoctial regions. We have spoken of extinct animals, because it is now admitted by all naturalists that the animals of our own acquaintance are not mere varieties of fossil species gradually changed by climate and other local circumstances, and that the probability is extremely remote of discovering even a small proportion of the supposed extinct quadrupeds in a living state in regions hitherto unexplored. Surprizing as the above facts may appear, there are others relating to the same department of the animal kingdom, which attest far greater changes in the form of the land and the ancient character of its inhabitants. At a yet earlier epoch that part of the globe where the continent of Europe now extends, was peopled with a race of terrestrial quadrupeds of an entirely different description; a race, of which most of the genera and all the species known to us in fossil remains have been since annihilated. Their skeletons are found entombed in strata evidently deposited in the estuaries of rives, and at the bottom of freshwater lakes, in a manner closely analogous to strata at present in the course of formation in our own lakes and rivers. In these last the remains of quadrupeds, as of oxen, beavers, and some more, are also found buried in considerable abundance, together with freshwater shells, and aquatic plants, sometimes corresponding generically with those which characterize ancient freshwater formations. The lost race of mammiferous quadrupeds above alluded to has been found in the neighbourhood of Paris, Aix, and Orleans, in Berri and Auvergne, in several parts of the South of France, and in Alsace. These remains are particularly distinguished by the abundance of genera belonging to a division of the order Pachydermata, which has now only three living representatives in the globe—the Tapir of South America, the Tapir of Sumatra, and the Daman of the Cape—whereas nearly forty fossil species of it are already ascertained. Among them are more than ten species of Palaeotherium, a genus resembling the Tapir and also in some particulars the Rhinoceros:

* Edinburgh Journal of Science, vol. v. p. 129. t Discovered near Montpelier by M. Marcel de Serres. Mém. de la Soc. Linn. de Paris. 1825. - Puy

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the largest of these equalled a rhinoceros in magnitude, others were of the sizes of the pig and the sheep, and the smallest was no larger than the hare.” Of the Lophiodon, a genus that also bore a considerable resemblance to the Tapir, more than twelve species have been determined; the largest of these was about the size of the rhinoceros, and the smallest about that of a lamb three months old. Of the extinct genus Anoplotherium, which differs extremely in anatomical character from any now known, six species are already ascertained:—the largest came near in size to the ass; another to the gazelle, which it is supposed to have rivalled in the elegance of its form; another did not exceed the hare in size, and some were still smaller. The species most frequently met with in the gypsum of Paris was “about the height of a wild boar, but had nearly the proportions of the otter; it had a thick and long tail, and probably swam well and frequented the lakes, in the bottom of which its bones have been incrusted with the gypsum there deposited.'S Of the extent of these ancient lakes the geologist can still form some idea, when he has traced in his map the boundaries of strata replete with the remains of freshwater animals and plants. Of the genus Antracotherium, two species have been found, one of the size of a Rhinoceros, the other smaller: these were intermediate between the Palaeotherium, Anoplotherium, and Hog. Of each of the genera Cheropotamus and Adapis, one species only is known, about the size of a rabbit. In the same formation with these herbivorous animals a few carnivorous ones are found; a Fox, a Gennet, a Bat, and a small Opossum, (a genus unknown till the discovery of America,) and some few others. Skeletons also of a dormouse and a squirrel occur, besides the bones of birds, crogodiles, freshwater tortoises, and fish; nor are shells wanting. The whole of these are either of extinct genera or of unknown species. The plants on which these large herbivorous animals were supported differed as widely as themselves from all known species. Palms, reeds, and many other kinds are met with in these strata, indicating upon the whole the vegetation not of tropical climates—as does the flora of our secondary formations and parficularly of the coal—but rather such as now clothes the countries bordering on the Mediterranean. No remains of the human species have been found with the above fossil animals, nor elsewhere in any stratum having pretensions to immemorial antiquity. It is nearly a century since Bishop Berkley remarked, that if Man had existed for so many ages as some nations and some philosophers have maintained, gems, medals, and implements, in metal or stone, would have lasted entire, as the shells and stones of the primeval world are preserved down to our time;” he might have added that human skeletons would have also attested the fact, for Cuvier has shown that there are strong grounds for believing these to be as little perishable in their nature as those of other animals. But the entire absence of all Quadrumana—such as the Gurang-outang, ape, monkey, baboon, and many other genera—is a circumstance not less striking. The animals of this family are at present as numerous as other grand divisions of Mammalia, and in their osteological characters they approach much nearer to the human species than any others. #. are almost exclusively confined at present to countries lying between the tropics, and never far exceed this limit;-but as the same may be said of the Elephant, Rhinoceros, Hippopotamus, Tapir, and other genera, as well as of the reptiles so abundant in a fossil state in Europe, some extinct species at least of the Quadrumana might have been looked for. An opinion was entertained soon after the commencement of the study of organic remains, that in ascending from the lowest to the more recent strata, a gradual and progressive scale could be traced from the simplest forms of organization to those more complicated, ending at length in the class of animals most related to man. And such is still the general inference to be deduced from observed facts, though some recent exceptions to this rule are too well authenticated to justify an implicit reliance on such generalizations. But what is most important with regard to the history of the above-mentioned lost race of quadrupeds, is the circumstance that both in the environs of Paris and in those of Orleans, as well as in Berri, and in a district not far from the Rhine, near Strasburgh, the strata inclosing them are again covered with marine deposits. A careful examination of the contents of these leaves no doubt that the sea returned and covered the land on which the animals had lived, and where the rivers and lakes were situated, in the beds of which their remains had been buried. To such an event M. Cuvier has attributed with great probability the annihilation of the quadrupeds then inhabiting the ancient continents. But to what known agents in nature can we ascribe such destructive catastrophes 2 The great winding sheets,’ says Lord Bacon, ‘that bury all things in oblivion are two, deluges and earthquakes.'t That these two causes have in fact conspired in former

* Cuv. Discours sur les Rev. p. 315, 316, 1825. - † Ib. p. 319. # Ib. p. 320. § Ib. p. 321. ages * Berkley, Min. Phil. vol. ii. p. 84.

t Cuvier, Discours sur les Rev., &c. p. 137. 1825.

t Essay on the Vicissitude of Things. WOL, XXXIV. N.O. LXVIII. K K periods

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