CHARACTERISTICS AND HABITAT. 21 



of iucisors, their powerful teeth being, no doubt, used 

 to gnaw through the roots which would otherwise 

 obstruct their subterranean course. * * * 

 Those of the upper jaw are always shorter than those 

 of the lower, and usually describe about three parts 

 of a circle. The larger incisors of the lower jaw form 

 a smaller segment of a larger circle."^ 



Among living rodents the beaver is the largest with 

 the exception of the capybara of South America, 

 which is about one-third larger.^ The form and 

 general appearance of the American beaver are well 

 known. Plis color is a reddish brown, but varying 

 in some localities to a yellowish tinge upon brown, 

 and in others to a glossy black. Reddish-brown, 

 however, is the prevailing color. I have two pelts in 

 my collection of a dark chestnut, this being the color 

 of the coarse fur or hair which in all cases determines 

 the general color of the skin. The fine or true fur 

 is of a clear uniform brown from the root to the tip, 

 and the staple is short. It varies in length from one- 

 half to three-quarters of an inch, while the coarse 

 hairs, which resemble bristles, are from one and three- 

 quarters to two and a half inches in length, and suf- 

 ficiently abundant to completely overspread the fur. 

 Black beavers are scarce, and appear to be confined 

 to higher northern latitudes. The fact that they are 

 sometimes found of this color is attested by Hearne. 

 '^' Black beaver," he remarks, "and that of a beautiful 



^ Nat. Hist, of the Mammalia. Lond. ed., 1848, ii. 1. 



^ One shot by Darwin at Montevideo weighed 90 pounds. In 

 general appearance it resembles the hare much more than the 

 beaver. 



