366 



SCOTT. 



[Vol. XI. 



ably discover in it the starting-point both of the Pecora and 

 of the Tragulina. The manus of Protoceras appears to have 

 been but Httle modified from that of this hypothetical form, 

 and some such type of manus might easily give rise to those 

 of all the later representatives of these various selenodont 

 lines. The hypothetical genus will doubtless also be found in 



Pecora. 



Tragulina. 



Gelocus, 



Protoc. 



Hypertrag. 



Leptom. 



Hypis. 



the Old World, for nothing seems clearer than that both 

 Pecora and Tragulina originated in that region, and the latter 

 group, as narrowly defined, has always been restricted to it. 

 From this supposed Uinta genus lead no less than four diver- 

 gent lines in the White River. Leptomeryx has kept nearly 

 the primitive type of skull, but has developed somewhat com- 

 plex premolars, with some advance in the structure of the 

 manus and still more in that of the pes. Hypertragulus has a 

 somewhat modified skull, but very primitive dentition, with 

 little change in the extremities beyond the coossification of 

 the ulna and radius, and of the cuboid and navicular. Hypis- 



