Darwinism Verified. 31 



back in time, as we reach the upper Pliocene, 

 the horse disappears, and we find the pliohippus, 

 very much like him. In the lower Pliocene this 

 creature is replaced by the protohippus, with 

 three toes like the hipparion. In the upper Mio- 

 cene we have the miohippns, with three well-de- 

 veloped toes like the anchitherium, and with the 

 rudiment of a fore-toe on the fore-foot. In the 

 mesohippus of the lower Miocene this rudiment 

 is a splint-bone, like those which represent the 

 later-disappearing toes in the modern horse. By 

 this time we find the ulna and fibula well devel- 

 oped and distinct from the radius and tibia. Still 

 further back, in the upper Eocene, comes the 

 orohippus, with four complete toes on the fore- 

 foot. And finally, in the lower Eocene, we get 

 the eohippus, which shows the rudiment of a fifth 

 toe on the front and a fourth foe on the hind foot. 

 In the structure of the teeth the other chief 

 point in which the modern horse is notably spe- 

 cialized we find a similar gradation back to the 

 ordinary mammalian type. 



The agreement of observed facts with the re- 

 quirements of theory is here complete, minute, 

 and specific ; and Professor Huxley may well say 

 that the history of the descent of the horse from 

 a five-toed mammal, as thus demonstrated, sup- 



