The Zoology of North American Big Game 



period, at least, it was contemporary with the ex- 

 isting European species. The black bear, with its 

 litter-brother of brown color, seems to be a genuine 

 product of the new world. 



Many differential characters have been pointed 

 out in the skulls and teeth of bears, and to a less 

 extent, in the claws; but while these undoubtedly 

 exist, the conclusions to be drawn from them are 

 uncertain, for the skulls of bears change greatly 

 with age, and the constancy of these variations, 

 with the values which they should hold in classifi- 

 cation, we do not yet know. 



It is not improbable that the reader may leave 

 this brief survey with the feeling that its admis- 

 sions of ignorance exceed its affirmations of cer- 

 tainty, and such is indeed the case, for the law of 

 scientific validity forbids the statement as fact, of 

 that concerning which the least element of doubt 

 remains. But the real advance of zoological 

 knowledge must not thereby be discredited, for it is 

 due to those who have contributed to it to remem- 

 ber that little more than a generation ago these 

 problems of life seemed wrapped in hopeless 

 obscurity, and the methods of investigation which 

 have led to practically all our present gains, were 

 then but new born, and with every passing year 



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