HISTORY OF THE CARNIVORA 



565 



777.7. 



B 



Another doubtfully distinct genus, ^Hemipsalodon, was 

 so closely like, 

 if not identical 

 with, the much 

 better known 

 European fPter- 

 odon, that the 

 latter may be 

 taken in place 

 of it. ^Pterodon 

 was similar in 

 most respects to 

 ■\Hy(Enodon, hut 

 distinctly less 

 advanced, and 

 though not the 

 ancestor of the 

 latter, serves to 

 connect it with 

 the older mem- 

 bers of the 

 series. '\Ptero- 

 don did not, so 

 far as we know, 

 penetrate North 

 America south 

 of the Canadian 

 border, occur- 

 ring in the lower 

 White River of 

 Alberta. In 

 this genus the 

 upper molars re- 

 tained a large 

 internal cusp. 



Fig. 279. — Lower teeth, right side, of fhysenodontids. A, t'Si- 

 vopa. B, ]Tritemnodon. C, ]Pterodon. D, ^Hywnodon. X, Ox- 

 ycena. The dotted line connects the first molar of each, lost 

 in ]Pterodon. See explanation of Fig. 280. (After Matthew.) 



