EIGHTH ANNUAL REPORT. 191 



many cats, including the lynxes, the bears, the otter, the wolver- 

 ine, the fisher, the marten, the mink and the beaver, are all more 

 or less recent immigrants from Eurasia. The moose and caribou 

 also probably came from the extreme north of the same conti- 

 nent. 



It is from the character of the animals above named, which 

 are nearly all of northern or subarctic habit, that we draw the 

 inference that this land connection between the continents lay far 

 to the north. From their close relationship to Eurasian animals 

 we can also infer that the connection persisted until very recent 

 times. Let us now examine the chief groups of the large Ameri- 

 can mammals one by one, and see what knowledge can be gained 

 from a study of the distribution of the members of each genus, 

 and of closely allied genera. 



CARNIVORES. 



BEARS. 



Taking up the Ursidae first of all, we find that all of the Amer- 

 ican bears belong to the type genus Ursus, although there are 

 several ill-defined subgenera. 



Like the deer, the bears are essentially northern animals, and 

 are widely distributed throughout Eurasia, with a single out- 

 lying species in North Africa. Their absence from the Ethiopian 

 region, or Africa south of the Sahara, is probably due to their 

 inability to pass the barrier of the deserts. 



If we take the common European brown bear, U. arctos, and 

 follow, by way of the great mountain ranges, its gradually in- 

 creasing racial variations across Europe and Asiatic Russia, we 

 find one type fading into another, until in the hairy-eared bear 

 of Amurland, U. piscator, and the great Kamchatkan fish bear, 

 U. behringiana, on the easternmost confines of the Old World, we 

 have bears very close in type and structure to the brown bears 

 of Alaska on the American side of the straits. The similarity 

 would probably prove even more striking than we now believe, 

 if we had more accurate data about this great fish bear, which, 

 until the discovery of the Kodiak bear, was the largest known 

 carnivore. 



Neither of these bears is inferior in size to the Pleistocene cave 

 bear, U. spelaeus, or its American congener, Arctotherium. 



More distantly related to these Eurasian bears are the grizzlies, 

 and most distant of all are the black bears. Leaving out of con- 



