Canadian Beaver 



2. Roof Rat. Mus rattus alexandrinus (Geoffroy). Colours 

 above brown and gray, below pure yellowish-white. Shape, 

 ears and tail exactly as in the black rat. 

 Range. In America, South Atlantic States. 



BEAVERS 



(Family Castoridce) 



The beavers are our largest gnawing animals. They are 

 heavily built and thoroughly adapted for an aquatic life, with 

 their wonderful broad, flat, naked tail and webbed hind feet. Both 

 fore and hind feet are four toed, but the second toe of the hind foot 

 is peculiar in having two claws. 



In the structure of its skeleton the beaver differs from all 

 the preceding "mouse-like" families and agrees with the squirrels 

 and marmots in having the two bones which form the lower leg 

 separate and not fused solidly together. 



We find in many groups of animals one or more members 

 adapted for life in the water and the beaver is the aquatic re- 

 presentative of the squirrel tribe, just as the muskrat is of the 

 mouse family and the otter of the weasel tribe. 



Canadian Beaver 



Castor canadensis Kuhl 



Length. 44 inches. 



Description. Tail and feet as described above, ears short. Body 

 thick and heavy, closely covered with fur. Colour dark bay 

 or blackish-brown, hairs tipped with chestnut, becoming 

 brighter on the head, sides of the neck and rump; ears black, 

 feet, legs and underparts seal-brown. 



Range. Northeastern North America, now nearly extinct within 

 the United States, represented to the South and West by 

 slightly different geographic races. 



Beavers are creatures with whose life history everyone is sup- 

 posed to be more or less familiar; the outstanding features of their 

 lives having been written and read over and over again by each 



MS 



