48 ZEBRAS, QUAG GAS, AND ASSES 



differ from rhinoceroses almost as much as nearly allied animals can. 

 The horse and its relations are cut out for speed and mostly for a life 

 on open plains, where their colouring, which is often of a compara- 

 tively brilliant type, is specially adapted to render them as nearly 

 invisible as possible. In place of the short, thick, three-toed limbs of 

 the rhinoceroses, their legs are long and slender, each terminating in a 

 single toe, which is protected by a firm and rounded hoof. Incisor 

 teeth, adapted for nipping grass, together with relatively small tusks, 

 or canines, in those of stallions, occupy the fore-part of both jaws ; and 

 the cheek-teeth have very tall, squared, prismatic crowns, with the 

 hollows between the enamel-covered columns of ivory completely filled 

 up by the substance known as cement. When worn, the crown- 

 surfaces present a very characteristic pattern. The body is completely 

 covered with hair ; the neck is maned ; the tail, which is long, may be 

 either covered with long hair throughout, or tufted at the end with the 

 same ; and peculiar hard callosities are present on the inner sides of either 

 the fore, or both pairs of limbs. The family is now confined, in a wild 

 state, to the Old World, the striped species being restricted to Africa. 



In place of wallowing in mud, like rhinoceroses, asses and zebras 

 are fond of rolling in sand or dust. Gravy's zebra, which is the most 

 northerly representative of the striped group, is markedly different in 

 many respects from both the typical zebra and the quaggas. The 

 arrangement of the stripes on the hind-quarters is altogether unique ; 

 the callosities on the fore-legs are as small as in the horse ; and, as in 

 that species, the mane extends on to the withers, and the tail-tuft is 

 large and full ; while the large, broad, arid thickly haired ears are 

 different from those of all other members of the family, which are 

 narrow and pointed. The large size of the ears and the narrowness of 

 the stripes appear to be adaptations to a life partially spent in thin 

 scrub, in which, as shown in the photograph by Lord Delamere, this 

 species is commonly found. 



The colour-pattern of Grevy's zebra is as follows : The alternate 

 dark brown or black and light stripes on the body, head, and limbs are 

 for the most part very narrow, widening out only on the lower jaw, 

 the neck, and the lower part of the thigh. On the flanks none of the 

 stripes bend backwards and upwards so as to extend on to the hind- 

 quarters, the upper portion of which is marked with vertical stripes 

 arranged concentrically round the root of the tail. The dorsal stripe 

 is broad, especially near the middle of the back ; there are no trans- 

 verse stripes on the under-parts, and the stripes on the nose practically 

 stop short of the nostril-patches, the nose itself being greyish. 



