164 THE MAMMALIA. 



World, and the Europe- Asiatic species in the Old. 

 It is only the ancestors of the Roe and the Hydro- 

 potes that must not be looked for in the Old World ; 

 they are scattered members of the group from the 

 other side of the ocean, like the Canadian species 

 which, in the days when the two continents were 

 connected by land, separated entirely from their 

 Europe- Asiatic cousins. It is found in the Qua- 

 ternary strata of Europe, e.g. in those of Louverne, 

 near Le Mans, where it lived as a separate family 

 by the side of the red deer, but soon afterwards, 

 for some unknown causes, vanished from this 

 locality and reappeared in the New World. 



The reduction of the side toes and the dis- 

 appearance of the one or the other ends of the 

 metacarpals took place after the still four-toed and 

 geologically older stag-shaped animals had acquired 

 antlers. This may have been the course taken 

 by their development, unless we are to assume 

 that the antlers appeared in different localities as 

 a parallel formation, yet not till after the separation 

 of the older hornless Euminants, which likewise 

 showed a reduction of the limbs spoken of above. 

 The latter case is very probable, and must be 

 drawn into the circle of combinations, for in Gelocus 

 we have become acquainted with a very ancient 



