| Dentition of Horse. |
This family consists of the true horses and the asses, which latter also include the zebra and quagga. Apart from the decided external differences between the horse and ass, they have one marked divergence, viz. that the horse has corns or callosities on the inner side of both fore and hind limbs, whilst the asses have them only on the fore limbs; but this is a very trifling difference, and how closely the two animals are allied is proved by the facility with which they interbreed. It is, therefore, proper to include them both in one genus, although Dr. Gray has made a separation, calling the latter Asinus, and Hamilton Smith proposed Hippotigris as a generic name for the zebras.
We have no wild horse in India; in fact there are no truly wild horses in the world as far as we know. The tarpan or wild horse of Tartary, and the mustang of South America, though de facto wild horses, are supposed to be descended from domesticated forms. In Australia too horses sometimes grow wild from being left long in the bush. These are known as brumbies, and are generally shot by the stock farmer, as they are of deteriorated quality, and by enticing away his mares spoil his more carefully selected breeds. According to Mr. Anthony Trollope they are marvels of ugliness.
The Indian species of this genus are properly asses; there are two kinds, although it has been asserted by many—and some of them good naturalists, such as Blyth—that the Kiang of Thibet and the Ghor-khur of Sind and Baluchistan are the same animal.
Incisors, 6/6; canines, 1—1/1—1; molars, 6—6/6—6; these last are complex, with square crowns marked by wavy folds of enamel. The incisors are grooved, and are composed of folds of enamel and cement, aptly described by Professor Boyd Dawkins and Mr. Oakley as being folded in from the top, after the manner of the finger of a glove the top of which has been pulled in. The marks left by the attrition of the surface give an approximate idea of the age of the animal. The stomach is simple—the intestinal canal very long and cæcum enormous.
[NO. 426. EQUUS ONAGER.]
The Wild Ass of Kutch (Jerdon's No. 214).
NATIVE NAMES.—Ghor-khur, Hindi; Ghour, or Kherdecht, Persian; Koulan of the Kirghiz.