Il] THE EXISTING EQUIDAE 37 



attached to differences in colour ; for though the two hybrid 

 foals, which have already arrived, closely agree in their colora- 

 tion, subsequent foals may differ considerably, and it is well 

 known that young wild horses from the western portion of 

 the Great Altai mountains differ in tint from those found 

 further east. 



" Of more importance than the coat-colour is the nature of 

 the hair. A Prejvalsky foal has a woolly coat not unlike that 

 of an Iceland foal. In the hybrid, the hair is short and fine 

 and only slightly wavy over the hind-quarters. It thus differs 

 but little from a thoroughbred or Arab foal. 



" The mane and the tail of the hybrid are exactly what one 

 would expect in a mule ; the dorsal band, 75 mm. wide over 

 the croup in the sire, has in the hybrid a nearly uniform width 

 of 12 mm. from its origin at the withers until it loses itself 

 halfway down the tail. The tail, which differs but little from 

 that of a pony foal, is of a lighter colour than the short, upright 

 mane, while the dorsal band is of a reddish-brown hue. In the 

 wild horse the dorsal band is sometimes very narrow (under 

 5 ram.) and indistinct. In the Kiang sire there are pale, but 

 quite distinct stripes above and below the hocks, and small 

 faint spots over the hind -quarters — vestiges apparently of 

 ancestral markings ; but in the hybrid there are neither in- 

 dications of stripes across the hocks or withers, nor spots on 

 the quarters. In having no indications of bars on the legs, 

 or faint stripes across the shoulders, the hybrid differs from 

 Prejvalsky colts ; it also differs in having a longer flank feather 

 and in the facial whorl being well below the level of the eyes. 

 As in the Kiang and some of the wild horses, the under surface 

 of the body and the inner aspect of the limbs are nearly white. 



" In the hybrid the front chestnuts (wrist callosities) are 

 smooth and just above the level of the skin; but instead of 

 being roughly pear-shaped, as in the Kiang, they are somewhat 

 shield-shaped, as in the Onager. In the wild horse the front 

 chestnuts are elongated. In the Exmoor dam the hind chest- 

 nuts (hock callosities) are 27 mm. in length and 10 mm. wide. 

 In the sire there is a minute callosity inside the right hock. 

 In the hybrid the hind chestnuts are completely absent. In 



