468 RUMINANTIA felted together by the movements of the stom- ach, and incrusted with a polished earthy de- posit of great hardness, are often found in the stomachs of ruminants, especially of the cow. Stomach of a Sheep. a. (Esophagus or pullet, b. Rumen, paunch, or first stomach, c. Keticulum, honeycomb, or second stomach, d. Pialterium or mum-plies. . Abo- niusuin, fourth or true stomach. The intestinal canal is very long and simple; compared with the length of the body it is, ac- cording to Meckel, as 12 to 1 in the camel and deer, 22 to 1 in the ox, and 28 to 1 in the sheep ; the large intestine is often scarcely wider than the small ; the csecum is always large, smooth, and without lateral bulgings. The eyes are wide apart, and so prominent that the range of vision is very extensive; the opening of the pupil is transverse, and the tapetum is exceed- ingly brilliant. The senses of hearing and smell are highly developed, and the cranial si- nuses are extensive. The mammsB are inguinal, and the teats four, except in sheep and goats, which have only two. The panniculus earno- sus musfle is remarkably developed, serving as a means of defence by shaking off flies and other stinging insects from the skin. In the camel there is a hump on the back, consisting principally of adipose matter developed in the subcutaneous areolar tissue, probably serving as a storehouse of nutriment to the animal during its long fasts in the desert. The hair is generally coarse, and never what would be called fur ; it varies from the harsh and shag- gy coat of the camel and the somewhat softer one of the llama to the fine wool of the sheep. Rumination is rendered necessary by the bulky character of the food as compared with its nutrient qualities; the timid animals of this order are naturally forced to take in a large amount of food in a short time, and then to flee from the carnivorous beasts always lying in wait for them to some retired place where they can remasticate it quietly. In camels the bolus is triturated alternately from side to side; in horned ruminants and in the gi- raffe it is always in one direction, either from right to left or from left to right. Rumi- nants embrace the animals most useful to man and the most easily domesticated ; whole races of men count their wealth by the numbers they possess of them, whether camels, llamas, goats, sheep, reindeer, or cattle. They are distributed all over the world except in Aus- tralia; the reindeer and musk ox are found in the polar regions of both hemispheres, the llamas and alpacas in South America, the cam- els in Asia and Africa, the giraffe and most antelopes in Africa, and the deer everywhere in suitable feeding places; in North America there are only two antelopes, only one of the sheep family, and two of the ox family ; there are no hollow-horned ruminants in South America as original species, though there are vast herds of wild cattle of foreign introduc- tion. The distribution of fossil ruminants was in some respects different from that of the liv- ing species ; for instance, the giraffe has been found fossil in France and the Sivalik hills, showing a warmer climate than now prevails in those regions; on the contrary, the reindeer has been found in 8. Europe, indicating also a temporary diminution of heat, probably from the extension southward of the ice during the glacial period. There are many interesting co- incidences of geographical distribution in geo- logical and the present times, bearing on the point of the origin of existing mammals, and in favor of the theory of such origin from the de- velopment of previously existing types, rather than from a distinct creative act after the en- tire destruction of the preceding fauna. Cam- els are found fossil in the Sivalik hills of India, llamas in the caverns of Brazil, musk deer in Asia and Africa, &c. ; deer (cercidw) are nu- merous in the diluvial formations of Europe, greatly resembling the present species, and, according to Pictet, some may be considered as the stock from which have been derived the present stag, reindeer, fallow deer, and roebuck, these, with also the goat and sheep, having sur- vived the catastrophes of this disturbed peri- od, and preceded the appearance of man in Europe. The fossil deer of Asia and America also very much resemble the existing species of these continents. The urus described by Julius Caesar (Do Bella Gallico, vi. 28) among the animals of Germany, and the aurochs even now living in the forests of Lithuania, are in- teresting in connection with the origin of do- mestic cattle ; these were probably indigenous, as a fossil urus and aurochs have been found in the diluvium of Europe. The fossil musk ox (ovibos) has been found in Siberia and North America, like the one now living in the polar regions. The ruminants show more transi- tions to other orders than would be supposed from the study of their living species, espe- cially in the direction of the odd-toed ungu- lates; they appeared after the latter, and un- der forms very nearly resembling existing spe- cies; there were none in the eocene tertiary, when almost all herbivorous mammals were of the latter, but appeared first in the miocene, and then became so numerous that in the sub- sequent epoch (pliocene) and during the dilu- vium they had entirely displaced the latter, at least in Europe. The sivatherium of the Sivalik hills resembled proboscidians in its heavy form, short neck, and probable trunk (as indicated by the nasal bones). Among the gigantic animals of this order may be men- tioned the great Irish elk, with enormous horns,
