136 THE WANDERINGS OF ANIMALS [OH. 



creatures which drifted towards that goal of per- 

 fection which has been reached only by the horse. 

 Number of toes, length of limbs and neck, shape of 

 the skull, pattern of teeth, general size, all were in 

 a flux towards certain improvements, but these many 

 characters did not all keep step in the same creatures. 

 The Hyracotheres of Eocene America and Europe 

 (scarcely larger than a cat, with four front and three 

 hind toes, e.g. the so-called Eohippos) are still so very 

 generalised that they lead to horses, rhinos and tapirs, 

 as well as to other distinct groups. We therefore 

 disregard them and begin with the Mesohippos of 

 American mid-Oligocene ; size of a sheep, three-toed, 

 with somewhat elongated limbs. Later relations, 

 during the Upper Oligocene, are perhaps Miohippos, 

 and Anchitherium which soon made its appearance 

 in Europe, flourishing there during the whole of 

 the Miocene, when its line became extinct. In any 

 case Anchitherium was an offshoot. Meanwhile in 

 American Miocene steady progress is represented 

 by a line of successive forms (Desmat-Para-Hy$)o- 

 Merychippus\ and all promised well, when, about 

 the end of the Miocene, this stock came to an end 

 in America. Whether members of this same stock 

 had spread into Asia, or whether there had taken 

 place a similar parallel evolution out of the ancient 

 common stock, we do not know. Suffice it to state 

 that with the Upper Miocene we have to start 



