Perissodactyla — Equus, Hipparion, etc. 



39 



Family Eqtjim: (Horses). — In all modern horses the digits Horses. 



are reduced to a single perfect toe on each foot (Fig. 38, C, p. 31) ; pier-case, 



hut this character does not hold good for the allied fossil forms, No. 10. 



several of which show a tendency to an increased number of Table-case, 



toes ; but the third is nevertheless always the largest. (See No ' 5 ' 

 the subjoined woodcut, Fig. -48, giving four examples, of the 

 Perissodactyle foot, after Marsh.) 



in 



Fig. 43. — Diagram showing the gradual loss of toes in the feet and increase in the complexity 

 of the teeth in the Equidaj. 

 1. Eqtms. 2. Bipparion 3. Anehitherium. 4. Orohippus. 



Recent. Pliocene. Miocene. (Hyracotherium.) 



h>, Fore-foot. 2a, Fore-foot. 3a, Fore-foot. Eocene. 



1 b. 26, 36, 4b, Upper Molar tooth of each genus. 4a, Fore-foot. 



The Eomau numerals indicate the corresponding toes present in each foot. 



In the next Pier-case are arranged the fossil remains of the 

 Horse froni the Thames Valley Brick-earths ; the raised beach 

 at Brighton ; Kent's Cave, Torquay ; they occur in nearly 

 all our British caves where other animal-remains have been 

 found ; in a Pleistocene deposit at Juvillac, and in the cavern 

 of Bruniquel, in France ; at Eschscholtz Bay, Arctic America ; 

 ]\Iinas Geraes, Brazil; and from Uruguay, in South America; 

 indeed, its fossil-remains may be truly said to be world-wide. 

 The present race of Wild-horses, which exist in such vast herds 

 on the Pampas, are not the descendants of the fossil horse of 

 South America, but have sprung from those introduced by the 

 Spaniards 350 years ago. Prior to the Spanish invasion the 

 natives of America had no knowledge of the horse. 



The three-toed and most immediate predecessor of the horse 

 (JEEvpparion, Fig. 48, 2 ), occurs fossil in the Pliocene deposits 

 of the Siwalik Hills in India ; in China and at Maragha, Persia ; 

 in Samos ; Pikermi, in Greece ; in France and Germany ; and 

 in the Bed Cra» of Suffolk. 



Pier-case, 

 No. 10. 



Pier-case, 

 No. 10. 

 Table-case, 

 No. 5. 



Hipparlon 

 and Equus, 



