GENERAL CONSIDERATIONS. 



Tlie Tei'iitorj- of Alaska beiug separated from the rest of the contineut of America by no 

 barriers wliicli are impassible to mammals, we shall not expect to discover a distinct mammalian 

 fauna within its borders. Lying partly within and partly without the Arctic Circle, and being- 

 bisected by the isothermal of 32^ F., we shall look in its southern portions for representatives 

 of the north-temperate fauna, and in its northern portions for representatives of the Arctic or 

 circumiwlar fauna. The facts bear out these a priori conclusions. We find no single species of 

 mammal within the boundaries of Alaska which is not to be found also without those boundaries. 

 Some enter the Territory from the east, or perhaps from across Bering Straits; others from the 

 .south. They are the fiimiliar species of the United States, British America, or Siberia and the 

 circumpolar zone generally. 



The interest attachiug to the mamm.xls of Alaska arises, therefore, not from their novelty 

 but rather from the fact that they are the northernmost representatives of their species. It is in 

 Alaska, as in Arctic British America, that we find the northern boundaries of the range of a 

 number of American mammals. We find species characteristic of a temperate region contending 

 with the rigors of au Arctic climate, few in numbers, and, as Mr. Allen has pointed out, small in 

 size. Oq the other hand, we find species rarely or never met with as far south as the United 

 States, having their center of distribution within the Arctic Circle, abundant and of large size. 



In IS70 Mr. Dall published a list of the mammals of Alaska, including the aquatic species. 

 This list comprises 70 species and subspecies of recent mammals, of which 25 belong to the orders 

 Piuuipedia and Cetacea. Sis of the species, however, are now generally regarded identical with 

 seven others in the list, and two additional species [Sorex Rossii and S. pachypus) appear never to 

 have been described. The number of valid species and subspecies is, therefore, reduced to 62. 

 The list is as follows: * 



Sorcx Forstcri. 



Sorex Gooperi. 



Sorex pachypus (uudescribed). 



Sorex Rossii (uudescribed). 



Lynx canadensis. 



Yidpes fulvus. 



CoMis occidentalis [= Canis lupus griseo- 



albiis.] 

 VidpesfulvKS decitssatus. 

 Vidpes fulvus argentatus. 

 Vulpes layopus. 

 Mustela Pennanti. 

 Mustela amcrieana. 



Putorius vison. 



Putorius pusillus [=P. vulgaris]. 



Putoriusnoveboracensis > 



Putorius Bichardsoni \ {=P-erminea] 



Gulo luscus. 



Lutra canadensis. 



Enhydra marina. 



Procyon lotor. 



JJrsus horribilis. 



Ursus Eichardsoni. 



Ursus americanus. 



Ursvs maritimus. 



•The fossil species givea by Mr. Dall are purposely omitted here ; also the Eskimo Dog, which may ormay not be 

 indigenous. 



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