EVOLUTION OF THE HORSE AND THE ELEPHANT 421 



of the world, the American Eohippus being represented 

 in Europe by an animal called Hyracotherium, or coney 

 beast. It is therefore uncertain where the group 

 actually originated. Nevertheless, the development of 

 the true horse can be traced in America, and in pre- 

 historic times numerous kinds of horses, large and small, 

 existed in this country. One of them, found in Texas, 

 had teeth larger than those of the largest living race. 

 In northern Texas and the adjacent parts of New 

 Mexico was a type of horse which has been named Equus 

 scotti, after the palaeontologist W. B. Scott, who has con- 

 tributed much to our knowledge of fossil mammals. 

 This species is known by very complete skeletons, so 

 that it is possible to form an excellent idea of its char- 

 acters. Its bones are remarkably like those of the 

 domestic horse, but it was relatively long-bodied and 

 short-legged, with a large head. Why it became extinct, 

 we do not know. Certainly the climate was not unfa- 

 vorable, as horses ran wild in vast numbers when later 

 introduced by the Spaniards. Man could hardly have 

 been responsible, for aboriginal man did not destroy the 

 game animals of this continent. Possibly some disease 

 destroyed the horse in America, leaving no proof of its 

 existence. 



6. In the Old World the genus Equus (Latin, a horse) Old World 

 presents a number of very distinct types, including the horses 

 horses proper, the asses, and the zebras. The typical 

 or true horses formerly abounded in Europe and Asia, 

 but today only one wild species exists. This animal, 

 found in western Mongolia, was named Equus przewal- 

 skii, after the well-known Russian explorer, Przewalski, 

 who obtained the first specimen nearly 40 years ago. 

 It is a pony with a relatively large head (here suggesting 

 the Equus scotti), a short, erect mane, and a tail with 



