134 
MAMMALIA. 
A Horse’s age is known by his incisors. The middle teeth begin to appear about fifteen days after birth ; and 
at two years and a half the middle ones are replaced ; at three and a half the two next follow ; and at four and a i 
half, the outermost or corner teeth. All these teeth, with originally-indented crowns, lose by degrees this character \ 
by detrition. At seven and a half or eight years, the depressions are completely eflaced, and the Horse is no ; j 
longer marked. ; [ 
The inferior canines appear at three years and a half, the superior at four years ; they remain pointed until the f 
sixth, and at ten begin to peel away. j 
The life of a Horse seldom extends beyond thirty years. Every one knows how much this animal varies in size iV 
and colour. The principal races even exhibit sensible differences in the form of the head, and in their proportions, j 
each being specially adapted for some particular mode of employment. 
The most beautiful and swift are the Arabs, which have contributed to perfect the Spanish breed, and with the ! 
latter to form the English : the stoutest and strongest are from the coasts of the North Sea ; and the most dimi- i 
nutive from the north of Sweden and Corsica. Wild Horses have a large head, frizzled hair, and ungraceful pro- 
portions. [If the figure of Pallas be correct, of the Wild Horse of northern Asia, it is doubtful, from the length of 
the ears and some other characters, whether a distinct species intermediate to the true Horse and the fol- ^ 
lowing be not represented. M. Serres suspects that a species of Equus now extinct is represented on the celebrated ' ;| 
mosaic of Palestrina. Bones of this genus are not uncommon in the older tertiary strata, and have even been found ■ 
in those of South America. . 
The Dzegguetai {Equus hemionus, Pallas).— A distinct species, intermediate in its proportions to the Horse and . 1 
Ass, which lives in troops in the sandy deserts of Central Asia. Colour isabelle, with black mane and [broad] ■ ' 
dorsal line ; a terminal black tuft to the tail. This was probably the Wild Mule of the ancients. ' 
The Ass {E. asinus, Lin.). — Known by its long ears, the tuft at the end of its tail, and the black line crossing the | 
dorsal one over its shoulders, which is the first indication of the transverse stripes that occur in the following I ' 
species. [Some of the young have obscure cross-bands on the legs.] Originally from the vast deserts of the | I 
interior of Asia, the Ass is still found there free and unreclaimed, in numerous troops, which migrate north and | i 
south according to the season ; hence it does not thrive in countries too much to the north. Its patience, sobriety, | ; ! 
hardy constitution, and the services which it renders to the poor, are well known to every one. The harshness of - ^ M 
its voice, or hmy, is occasioned by two small peculiar cavities situate at the bottom of the larynx. | • | 
The Zebra {E. zebra, Lin.). — Nearly the form of the Ass, and everywhere transversely striped with black and | ^ \ 
white in a regular manner. It is indigenous to the whole south of Africa. We have known a female Zebra f ! 
produce successively with the Horse and the Ass. I ! 
The Couagga {E. quaccha, Gm.), resembles the Horse more than the Zebra, but inhabits the same country as the 
latter. Its coat is brown on the neck and shoulders, transversely striped with whitish ; the crupper reddish-grey, 
and tail and legs whitish. Its name expresses the sound of its voice, which is not unlike the bark of a Dog. 
The Onagga or Dauw {E. montanus, Burchell). — Another African species, inferior [?] in size to the Ass, but 
with the handsome form of the Couagga, and of an isabelle colour, striped with alternately broader and more 
narrow black markings on the head, neck, and body. The hinder stripes are disposed obliquely forward, and the 
legs and tail are white. 
THE EIGHTH ORDER OF MAMMALIANS,— 
-in 
RUMINANTIA,- 
Is, perhaps, the most natural and the best determined of the whole class, for all the species 
which compose it appear to have been constructed on the same model, and the Camels alone 
present some inconsiderable exceptions to the general characters of the group. 
The first of these characters is that of having no incisors in the upper jaw, while the 
inferior has always eight, [the two outermost of which represent canines, as can be easily 
shown]. They are replaced above by a callous pad. Between the incisors and the molars 
is a wide space, where, in some genera, there are one or two canines.* The molars, almost 
always six in number above and below, have their crowns marked with two double crescents, 
the convexity of which is turned inwards in the upper, and outwards in the lower jaw. 
The four feet are each terminated by two toes, and by two hoofs, which present a flat sur- 
face to each other, appearing as though a single hoof had been cleft ; hence the names that 
have been applied to these animals, of cloven-footed, bifurcated, &c. 
Behind the hoof there are always two small spurs, which are vestiges of lateral toes. The 
* Though acquainted with all the subdivisions of Ruminantia, we 
have never seen more than one canine in any animal whatever ; and 
in the Camels, wherein the inferior canine has been recognized as 
such, there are never more than six lower incisors — Ed. 
