NORTH AMERICA AND THE WEST INDIES 49 



stands of old timber and is much given to foraging and traveling 

 on the ground. Hunters often employ dogs to tree the squirrels, 

 after which they may be shot with little difficulty. At the 

 present time it may be called locally uncommon in less settled 

 areas from south-central Pennsylvania to the mountains of 

 central Virginia and West Virginia. 



Family CASTORIDAE: Beavers 



Beavers of the genus Castor are the only living members of 

 this family of rodents; they are of circumboreal distribution 

 in the watered and forested regions of the north-temperate 

 zone. Since prehistoric times they have been of great impor- 

 tance in the economy of the human race, chiefly for their fur 

 and their meat. The Old World beavers (Castor fiber and 

 races) are regarded as a species distinct from the North Ameri- 

 can species (C. canadensis), but the actual differences are slight, 

 as in the proportionate depth of the rostrum (less in the Old 

 World animal) and the length of the nasal bones (extending 

 back of the lacrimal level more in the Old World animal). 

 Of the New World beaver, a nurfber of slightly marked races 

 have been described, depending on minor differences in color 

 or in the size or the relative shapes of some of the cranial bones. 

 Everywhere as the country has been opened and settled the 

 beaver has been so reduced or extirpated that its present num- 

 bers and distribution are but a fraction of their original extent. 

 In various eastern localities reintroductions have taken place, 

 with varying success. The literature on the American beaver 

 is extensive, for probably few of our native mammals have been 

 more often written about. In the following account of the 

 various races only an outline of the main points in the history 

 can be given, and in many cases it is hardly possible to obtain 

 accurate details of recent date. The various races may be 

 taken up in alphabetical sequence. 



CANADIAN BEAVER; NORTHEASTERN BEAVER 



CASTOR CANADENSIS CANADENSIS Kuhl 



Castor canadensis Kuhl, Beitrage zur Zoologie, 1820, p. 64 (Hudson Bay). 

 FIGS.: Radford, 1908, 10 unnumbered pis. (col. exterior, photos, skull, works); Nelson, 

 1916, p. 443 (col.); Elliot, 1901, p. 115, fig. 27 (skull). 



