128 PROCEEDINGS OF THE ACADEMY OF [1894. 



americanus is concerned, viz. : that leaving out marlthnns, none of 

 our North American bears can be accorded higher rank than that of 

 subspecies of ardos. Indeed were it not for the combination of 

 certain skull and tooth averages, with some tolerably constant differ- 

 ences in color and the increased size of the claw in American speci- 

 mens, it is doubtful if even this distinction could be maintained be- 

 tween arctos and Iiorribilis ; both the large, broad-headed grizzlies of 

 California and the smaller, northern examples, pretty well closing 

 up the gap. 



In extreme cases americanus has become more differentiated and 

 is constantly smaller, but even here we have seen that the assumed 

 specific characters intergrade ; it is, however, better separated from 

 arctos than is horribiUs, and through its extreme forms the path to 

 cmnamomeus is perhaps indicated — as a large series of the latter may 

 show. Among Asiatic bears, isabelliniis and probably syriacus are 

 also closely related. The general direction of these relationships 

 appears to point to some such scheme as this : 



arctos • 



horrihilis 



cmnamomeus 

 americanus 



isabellinits S7jriaeiis 



Audubon and Bachman's name appeal's to be correctly applicable 

 to the bears whose cranial and dental characters are here given for 

 the first time. They agree sufficiently well in external features and 

 in geographical range as far as we have present knowledge, and the 

 assignment which I here make of them, I must regard as much pre- 

 ferable to the alternative course of imposing upon them a new name. 

 In the paper on Ursiis luteolus, already referred to. Dr. Merriam 

 denies the applicability of cinnamomeus to luteolus, and inferentially 

 to the present species, "because ciiiniuuomum was based on an animal 

 from the northern Rocky jNIountains,. which has small molars, like 

 the common black bear of the northeastern United States." This 

 assumption, however, has no basis but in the fact that up to the 

 present time we have known no brown bear from the Rocky Moun- 

 tain region other than the small- toothed americanus, which has 

 erroneously been supposed to be the animal on which Audubon and 



