CANID^. 



893 



Fig. 33. — Nimravtu gomphodus, two-fifths natural size. Mus. Cope. 



CANIDaE. 



Species of this family were very abundant during the Miocene period 

 in North America as in Europe. Tliose of the Lower and Middle Miocene 

 epochs belong to genera allied to, but distinct from, Canis ; while those of 

 the Upper Miocene (Loup Fork) and later horizons pertain to the latter 

 genus, with a few exceptions. The characters of the Miocene genera are as 

 follows : 



I. Molar formula f |. 



Humerus with epitrocblear foramen AmpMcyon. 



II. Molar formula ^ f. 



a. Xo anterior lobe of sujierior sectorial. 

 Humerus with epitrochlear fdramen. 



Inferior sectorial heel trenchant Temnocyon. 



Inferior sectorial heel basin-shaped Galecymts. 



Humerus witliout epitrochlear foramen. 



Inferior sectorial heel basin-shaped Canis. 



aa. An anterior lobe of superior sectorial. 



Heel of lower molar not trenchant ; no epitrochlear foramen JFAurodon. 



HI. Molar formula f r|. 



Heel of inferior sectorial trenchant Euhydrocyon. 



IV. 3Iolar formula I i. 



Heel of inferior sectorial basin-shaped Oligohiinis. 



V. Molar formula | f. 



First inferior molar two-rooted Hytenocyon. 



To the^e genera 1 refer twenty-five species of the American Miocenes. 



