EIGHTH ANNUAL REPORT. 193 



The type species, U. horribilis, is distributed throughout the 

 Rockies from Alaska to Mexico, with two subspecies, the Alas- 

 kan grizzly, U. alascensis, described from Norton Sound, the ex- 

 istence of which is still in dispute, and the great California 

 grizzly, U. horriaeus. 



THE BROWN BEAR GROUP. 



The third and, judged by the same tests, the latest group to ar- 

 rive was that of the Alaskan brown bears. Its members have 

 departed but little from the Eurasian bears, and a comparison of 

 forms may bring the resemblance still closer. 



These bears have known a distribution along the South Alaska 

 coast as far as the mountains at the head of Portland Canal, and 

 extend probably far inland toward the north. While the group 

 has split up into a number of races, the gradations are scarcely 

 distinguishable, and it is probable that the further examination 

 of specimens from intermediate points will result in the merging 

 of some of the species. 



The American type of the brown bear is the great Kodiak bear, 

 U. middendorM, from Kodiak and adjoining islands. It is the 

 largest of all living carnivores, and is closely related to the main- 

 land bear along the adjoining coast. 



These mainland bears have been assigned to a number of spe- 

 cies or subspecies, beginning on the west in the Alaskan penin- 

 sula: U. merriami or U. gyas; farther to the east, U. kidderi of 

 Cook Inlet, U. dalli of Yakutat Bay, and U. sitkensis, which 

 appears to be the most eastern of the group. 



Turning now to the fossil record, we find no fossil bear in 

 North America until the Pleistocene, whereas bear abounded in 

 Europe in the Lower Pliocene. A related form, known as Arcto- 

 therium, entered South America during the Pleistocene, but un- 

 doubtedly came from the north, as it has also been found in the 

 Pleistocene cave deposits of California. 



MUSTELINES OR WEASELS. 



Of the American members of the Mustelidae there are but three 

 genera which are peculiar to America. First, the American 

 badger, Taxidea, which dates back at least as far as the Pleisto- 

 cene; and the skunks, Mephitis and Spilogale, neither of which 

 have Eurasian equivalents nor American ancestors. Paleontol- 

 ogy gives us but little light on these three genera. 



