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Show 96 crlANGE OF CLIMATE were in existence, our opportunities are necessarily more limited of procuring evidenc.e from t~e con~ents ?f m~rine strata. It is only in lacustrme deposits, or m ancient riverbeds, or in the sand and gravel of land-floods, or the stalagmite of ancient caverns once inhabited by wild beasts, that we can obtain access to proofs of the changes which animal life underwent during those periods when the marine strata already adverted to were deposited farther to the south. As far, however, as proofs from analogy can be depended upon, nothing can be more striking than the harmony of the testimony derived from the last-mentioned sources. We often find, in such situations, the remains of extinct species of quadrupeds, such as the elephant, rhinoceros, hippopotamus, hyrena, and tiger, which belong to genera now confined to warmer regions. Some of the accompanying fossil species, which are identifiable with those now living, belong to animals which inhabit the same latitudes at present. :'If It seems, therefore, fair to infer, that the same change of climate which has caused certain Indian species of testacea to become rare, or to degenerate in size, or to disappear from the Mediterranean, and certain genera of the Subapennine hills, now exclusively tropical, to retain no longer any representatives in the adjoining seas, has also contributed to the annihilation of certain genera of land-mammifera, which inhabited the continents at about the same epoch. '!'he mammoth (Elephas primigenius), and other extinct animals of the same era, may not have required the same temperature as their living congeners within the tropics ; but we may infer, that the climate was milder >~~ Bones of the mammoth have been recently found at North Cliff, in the county of York, in a lacustrine formation, in which all the land and fresh-water shells, thirteen in number, have been accurately identified with species and varieties now existing in that country. Bones of the Bison, an animal now inhabiting a cold or temperate climate, have also been found in the same place. That these qund· rupeds, and the indigenous species of testacea associated with them, were all con· temporary inhabitants of Yorkshire (a fact of the greatest importance in geology), has been established by unequivocal proofs, by the Rev. W. V. Vernon, who caused a pit to be sunk to the depth of more than two hundred feet, through undis· turbed strata, in which the remains of the mammoth were found imbedded together with the shells, in a deposit which had evidently resulted from tranquil waters.-Phil. Mag. Sept. 1829, and Jan. 1830. These facts, as Mr. Vernon olJserves, indicate that there has been little alteration in the temperature of these latitudes since th~:~ mammoth lived there. ~IBERIAN MAMMOTHS. 97 t~an that· now experien~ed in some of the regions once inhabited by th~m'. because, m Northern Russia, where their bones ~re fo~nd m Immense. numbers, it would be difficult, if not Imp~ssible, fo~ su~h ammals to obtain subsistence at present, durmg an arctic wmter *· It has been said that as th d l · 1 · ' e mo ern no.r t 1ern .a mma s migrate ' the Siberian elephant m ay a 1s o h ave sh~ted !ns place during the inclemency of the seasont' but this co~Jecture seems forced, even in regard to the elephant and st~U more so, when applied to the Siberian rhinoceros; found m the frozen gravel of that country; as animals of this genus at·e heavy and slow in their motions, and can hardly be supposed to. have accomplished great periodical migrations to southern latitudes. That the mammoth, however continued for a long time t? exist in Siberia after the winters l~ad become ~xtremely col~, IS demonstrable, since their bones are found in Icebergs, and m the frozen gravel, in such abundance as could only have been supplied by many successive generations. So many sk~leto~s could ~ot have belonged to herds which lived ~t one time m the district, even if those northern countries ad on~e b~en clothed with vegetation as luxuriant as that of an Indian JUngle. But, if we suppose the change to have ~~e~ ex~remely slow, and to have consisted, not so much in a Immutwn of the mean annual temperature, as in an alteration fr?m what has been termed an "insular" to an "excessive" chmate, from one in which the temperature of winter and s~mmer were nearly equalized to one wherein the seasons were vs~oble~tly contrasted, we may' perhaps, explain the phenomenon Ienaand oth er arcti·c regw· ns, after having possessed for• B. oD' ej" a m 0 r e um·J~. orm temperature, may, after certain changes m t le form of the arctic land, have become occasionally exposed of :r! f;ulyt agr~e wit~ Dr. Fleming, that tht~ kind of food which the existing species Jectur; l:n pre .ers will not enable us to determine, or even to offer a feasible con· with th oncer~mg that of the extinct species. No one, as he observes, acquainted h e. grammeous character of the food of our fallow-deer stag or roe ,vould ona vwe haiscsl 1gthn ed a r~ c h en t o t h e rem· -deer. But, admitting that th' e tree' s and h'e rbage h 1 e fosstl elephants and rhinoceroses may have fed were not of a tropical c aracter but s h ·h . llll • b b'l uc pet aps as now grow m the temperate zone, it is still hi,.hly pro a 0 that the e r t f h' h . 0 t v ge a ton w tc nourtsbed these great quadrupeds was as esvc an Y as that of ou x· arc ti c reg1·0 us, o· r that 1· t was covered during the greater l>art of ery year by snow. t Dr. Fleming, Edin. New Phil. Journ. No. xii. p. 285. April, 1829. Vot. I. ' II |