toes, formed
of the same three digits. In the extinct _Paleotherium_ also the foot
is constituted very much as in the rhinoceros."

FAMILY EQUIDAE--THE 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.

[Illustration: Dentition of Horse.]

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.

_GENUS EQUUS_.

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 caecum
enormous.

NO. 426. EQUUS ONAGER.
_The Wild Ass of Kutch_ (_Jerdon's No. 214_).

NATIVE NAMES.--_Ghor-khur_, Hindi; _Ghour_, or _Kherdecht_,
Persian; _Koulan