272 BRITISH MAMMALS 



thickly on the skin, and appears to have formed great bunches 

 of hair round the feet (somewhat as we see in the artificially- 

 developed cart-horse). As in the case of the mammoth, the 

 undergrowth of woolly hair was supplemented by fringes of 

 longer and coarser hairs on certain parts of the body, such as 

 along the flanks and throat and the edges of the ears. The hair 

 of one of the specimens found in Siberia is said to have been 

 ash-coloured. 



In view of the fact that human remains and implements have 

 unquestionably been found associated with the remains of the 

 woolly rhinoceros in Belgium, England, France, etc., and that 

 this family certainly co-existed in Europe with man, it is 

 very strange that amongst all the drawings or sculpturings of 

 Prehistoric man discovered (mainly in France), apparently there 

 is no representation amongst them of so striking and terrible a 

 beast as must have been this immense, two-horned, hairy 

 rhinoceros. 



FAMILY: EQUID^E. THE HORSES 



In this family the five toes of the primitive Ungulate have 

 gradually dwindled to only one functional toe, with, in the 

 earlier forms, two small useless toes in addition, one on either 

 side of the big third toe or finger. These (the second and fourth 

 digits of the mammalian hand or foot) are only represented by 

 the splint bones in the horses of to-day. Even the modern 

 horse, however, occasionally " reverts " to a former condition, 

 and foals are sometimes born and grow up with the traces of as 

 many as four toes in all, some even with one or other of the 

 splint bones enlarged into a complete toe, with a hoof at the end. 

 Another condition of specialisation in the True Horses lies in the 

 molar teeth. 



The horses have six incisors above and below, and canines 

 in both jaws, though in the modern species canines are sometimes 

 wanting in the female. The incisors of horses have a peculiarity 

 not found in the teeth of any other mammal, in that a curious 

 deep pit, or groove, is formed in the crown of the tooth, 



