off from the rest of the cavity, and into which the fluid portion only of the contents of the stomach is allowed to enter.[186] The placenta is diffuse, as in the Suina and Tragulina, not cotyledonary, as in the Pecora. Finally, the _Camelidæ_ differ not only from other Ungulates, but from all other mammals, in the fact that the red corpuscles of the blood, instead of being circular in outline, are oval, as in the inferior vertebrated classes. _Camelus._[187]—Dentition of adult: _i_ ¹⁄₃, _c_ ¹⁄₁, _p_ ³⁄₂, _m_ ³⁄₃; total 34. First upper premolar simple, placed immediately behind the premaxillæ, and separated by a long diastema from the penultimate tooth of that series. Lower incisors somewhat proclivous, the outermost the largest. Skull elongated, with an overhanging occiput, orbits completely surrounded by bone, and the premaxillæ not articulating with the arched and somewhat elongated nasals. Vertebræ: C 7, D 12, L 7, S 4, C 13-15. Ears comparatively short and rounded. One or two dorsal adipose humps. Feet broad, with the toes very imperfectly separated. Tail well developed, tufted at the end. Hair nearly straight, and not woolly. Size very large and bulky. The genus is now represented by two species, viz. the single-humped Arabian Camel (_Camelus dromedarius_), and the double-humped Bactrian Camel (_C. bactrianus_, Fig. 114).[188] The former is quite unknown in a wild state, but it is reported that wild Bactrian Camels occur in the more remote parts of Turkestan. The latter species is found in a domesticated state throughout a large portion of Turkestan and the neighbouring region, extending as far as the Crimea in the west and to Lake Baikal and Pekin in the east. It is a heavier and more clumsy animal than the Arabian Camel, with thicker hair, shorter legs, and the feet more callous and better adapted to a hard ground. The hair is most developed upon the top of the head, neck, humps, arm, and wrist. Bactrian Camels are occasionally brought over the stupendous mountain passes south of Yarkand to within a few days’ journey of Leh, in Kashmir territory. [Illustration: FIG. 114.—The Bactrian Camel (_Camelus bactrianus_).] The Arabian Camel is commonly employed as a beast of burden in Africa and India, and has of late years been introduced into Australia for the same purpose; it is especially valuable in crossing long stretches of arid desert from its power of existing for a considerable period of time without water. The female goes fully eleven months with young, and produces but a single calf at a birth, which is suckled for a whole year. In disposition the Camel is surly and subject to furious outbursts of temper, especially during the rutting season. At such periods the male utters a peculiar and highly disagreeable bubbling noise in its throat, well known to all who have travelled in India with Camels as their transport. It has been said that the Camel is docile, but Palgrave observes:—