SEPTEMBER 29, 1877. SCIENTIFIC AMERICAN SUPPLEMENT, No
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SEPTEMBER 29, 1877. SCIENTIFIC AMERICAN SUPPLEMENT, No. 91. 1449 9 in. of the top is a suction pipe, 3 in. in diameter, referred equine, and some of the species equaled the ass in size. there by the American elephant, which preferred a milder to in the description of chamber 1, and 1s earried out to the There are still three toes on each foot, but only the middle climate. Remains of the latter have been met with in Can nearest stream of water to keep up the ignition of chamber 1, one, corresponding to the single toe of the horse, comes to ada, throughout the Uuited States, and in Mexico. The last and thus dispense with the use of a fire ; but the apparatus the ground. The genus resembles most nearly the hipparion of the American. mastodons and elephants became extinct in is provided with a suitable fire-place and ash-pit for use of Europe. In the pliocene, we have the last stage of the the post-tertiary. when no stream of water is near at· hand for feeding this series before reaching the horse, in the genus pliohippus, Perhaps the most remarkable mammals yet found in suction pipe. which has lost the small hooflets, and in other respects is America are the tillodontia ,which are comparatively abun very equiue. Only in the upper pliocene does tbe true equ1ts dant in the middle and lower eocene. These animal s seem [Continuedfrom SUPPLEMENT No. 90.] appear, and complete the genealogy of the horse, which in to combine the characters of several different groups, viz. : the post-tertiary roamed over the whole of North and South The carnivores, ungulates and rodents. In the genus Tillo ANCIENT LIFE IN AMERICA. America, and soon after became extinct. This occurred long tlterium, the type of the order, and of the family tillotheridro, PROF. ARSH before the discovery of the continent by Europeans, and no the skull resembles that of the bears; the molar teetlrare all By O. C. M . satisfactory reason for the extinction has yet been given. of the ungulate type; while the large incisors are verysimilar SLOTHS THAT WENT TO SOUTH AMERICA. Besides the characters I have mentioned, there are many to those of rodents. The skeleton resembles that of the car others, in the skeleton, skull, teeth, and brain of the forty or nivores, It is frequently asserted, and very generally believed, that more intermediate species, which show that the transition edentata THE PRIMATES, INCLUDING MAN. the large number of huge which lived in North from the eocene eohippus to the modern equus has taken place America durin� the post-pliocene, were the results of an ex in the order indicated, and I believe the specimens now at tensive migratlOn from South America soon after the eleva We come now to the highest group of mammals, the pri· New Haven will demon�trate the fact to any anatomist. mates, which include the lemurs, the apes, and man. This tion of the Isthmus of Panama, near the elose of the tertiary. They certainly carried prompt conviction to the first of anat· No conelusive proof of such migration has been offered. and order has a great antiquity, and even at the base of the omists, who was the honored guest of the Association a year eocene, we findit represented by several genera belongingto the evidence, it seems to me, so far as we now have it, is ago, whose genius had already indicated the later genealogy directly opposed to this view. No undoubted tertiary eden the lower formsof the group. In consiooringthese interest of the horse in Europe, and whose own researches so weIl ing fossils, it is important to have in mind that the lemurs, tates have yet been discovered in South America, while we qualified him to appreciate the evidence here laid before have at least two species in our miocene, and during the which are usually regarded as primates, although at the bot him. Did time permit I might give you at least a probable tom of the scale, are only found at the present day in Mada deposition of our lower pliocene large individuals of this explanation of this marvelous change, but justice to the com· group were not uncommon as far north as the forty-third gascar and the adjacent regions of the globe. All the Amer· rades of the horse in his long struggle for existence de ican monkeys, moreover, beloug to one group, much above parallel of latitude. on both sides of the Rocky Mountains. mands that some notice of their efforts should be placed on In view of these facts and others which I shall lay before the lemurs, while the Old Worfd apes are higher still, and record. most nearly approach man. you, it seems more natural to conelude from our present THE mSl'ORY OF THE SWINE. knowledge that the migration which no doubt took place In the lower eocene of N ew Mexico, we find a few repre- was from north to south. The edentates finding thus in The artiodactiles, or even-toed ungulates, are the most sentatives of the earliest known primates, and among them lemur limnotherium, South America a congenial home flourished greatly for a abundant of the larger 'mammals now living; and the group are the genera avus and eacn the type time, and, although the larger forms are now. all extinct, dates back at least to the lowest eocene. Iii every vigorous of a distinct family. Thes�enera became very abundant type which to survive many geologic in the middle eocene of the West, and with them are found diminutive representa�ives of the group still inhabit the same primitive was destined le region. changes, there seems to have been a tendency to throw off many others, aIl, however, ineluded in the two families, limnotheridro. ORIGIN OF HOOFED ANIMALS. lateral branches, which became highly specialized and soon muravidro and died out, becaURe they are unable to adapt themselves to new In the miocene lake basins of the West, only a single spe· The ungulates are the most abundant mammals in tbc pr m tes conditions. The narrow path of the persistent suilline type, eies of the i a have been idcntificd with eertainty. This tertiary, and the most important, since tbey inelude a great in throughout the whole tertiary, is strewn with the remains was found the oreodon beds of Nebraska, and belongs to variety of types, some of which we can trace through their laop limnotherid(Jj of such ambitious offshoots, while the typical pig, with an the genus ünecus, apparently related both to various changes down to the modified forms that represent obstinacy never lost, hasheldout in spite of catastrophes and and to some existing South American monkeys. In the pli them to-day. Of the various divisions in this comprehen evolution, and still lives in Ameriea to-day. The enus ocene and post-pliocene of North America, no remains of sive group, the perissodactyle, or odd-toed ungulat es, are g platygonus is re(lresented by several s ecies, one of which was primates have yet been found evidently the oldest, and throughout the eocene are the pre p very abundant III the post-tertiary of North America, and is In the post-pliocene deposits of tbe Brazilian caves, remains vailing forms. Although all of tbe perisRodactyles of the apparently the last example of a side branch, before the of monkeys are numerous, and mainly belong to extinct spe· ear lier tertiary are more or less generalized, they are still cebu American suilliues culmlllate in existing peccaries. The eies of callithri!lJ, s and jacchus, all living South Ameri· quite distinct from the artiodactyles, even at the base of the feet in this species are more specialized than in the living ean genera. Only one extinet geuus, protopitheclls, whieh eocene. One family, however, the cor.llphodontid!lJ, which is forms; and approach some of the peculiar features of the embraced animals of large size, has been found in this pe weU represented at this horizon, both in America and Eu. ruminants; as, for example, a strong tendency to coalescence culiar fauna, rope, although essentially pel'issodactyle, possesRes some It in the mctapodial bones. The genus platy,qonu8 became ex- is a noteworthy fact, that no traces of any anthropoid characters which point to a primitive ungulate type from tinct in the post-tertiary, and the later and existing species apes, or indeed of any Old World monkeys, have yet been which the present orders have been evolved. Among these are all true peccaries. No authenticated remains of the detected in Ameriea. Man, however, the highest of the pri. characters are the diminutive brain, which in size and form genera BUS,pormts, phacoch!lJrus, or the allied hippopotamus, mates, has left his bones and bis works from the Arctic Cir approaches that of the reptil es, and also the five-toed feet . the old world suillines have been found in America although ele to Patagoma. Most of these specimens are c1early post. from which all the various forms of the mammalian foot to several announcement� to that effecthave been ma'de. i tertiarr, although the�e is cons�derable evidence poin�ing have been derived. Of this family, only a single genus, man m In the series of gent,lrie forms between the lower eocene t�e eXlstence or our phocene. All tbe remalllS yet cOl'yphodon (bothmodon), is known, but there were several "omo, eohyus and the existing dicotyles, which I have very briefly dlscovered 1!elong to t!Ie weIl marked genus and appa distinct species.