The Zoology of North American Big Game 



obvious, but as we trace them back into the past 

 we follow on converging lines, and in our search 

 for the prototypes of the carnivora we are led to 

 the Creodonta, contemporary with Condylarthra, 

 which we have seen giving origin to hoofed beasts, 

 but outlasting them into the succeeding age. These 

 two groups of generalized mammals approached 

 each other so nearly in structure, that it is even 

 doubtful to which of them certain outlying fossils 

 should be referred, and the assumption is quite 

 justified that they had a common ancestor in the 

 preceding period, of which no record Is yet 

 known. 



The most evident points In which Carnivora 

 differ from Ungulata are their possession of at 

 least four and frequently five digits, which always 

 bear claws and never hoofs; all but the sea otter 

 have six small incisor teeth In each jaw; the 

 canines are large ; the molars never show flattened, 

 curved crests after the ruminant pattern, but are 

 more or less tubercular, and one tooth in the hinder 

 part of each jaw becomes blade-like, for shearing 

 off lumps of flesh. This tooth is called the sec- 

 torial, or carnassial. 



Existing carnivores are conveniently divided into 

 three sections : Arctoidea — bears, raccoons, otters, 

 skunks, weasels, etc. ; Canoidea — dogs, wolves and 



