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TEXT-BOOK OF ZOOLOGY 



being much stouter, and only the hind-feet being webbed. Speed in 

 swimming, however, is not of such importance to this animal, as it is a 

 peaceful vegetable-eater, and does not, like the otter, feed on animals 

 which flee at the sight of their enemy. The absence of webs on the 

 fore-feet is also an advantage, as 

 otherwise it would not be able to 

 use them so effectively in its work 

 as a builder [see Section B (c)]. 



(c) The tail, which is broad, 

 placed horizontally, and covered 



BEAVERS. B., HUTS; D., DAM. 

 The animal in the foreground gnawing a branch is about one-fifteenth natural size. 



with scales, acts as a rudder. The animal changes its direction, how- 

 ever,, chiefly by the flexibility of it vertebral column, especially of its 

 neck, like other swimming mammals. 



(d) The ears are short and nearly hidden in the fur ; in swimming 

 they are laid back so far as to close the auditory passage. 



B. The Beaver as a Builder. 



With the strong claws of its fore-paws it digs an 



passages, 



underground 



dwelling. One or more long passages, which terminate below the 

 surface of the water, lead to the chamber, the bottom of which is covered 



