THE LIFE OF MAMMALS 
a tuft of quills at the end, whose rattling, when the animal 
gets excited, recalls that of a rattlesnake. These Old World 
porcupines dwell in burrows of their own digging, or in con- 
Brownell, Phot. 
THE NORTH AMERICAN OR “CANADA” PORCUPINE. 
venient and softly bedded hollows among rocks, whence they 
sally forth at night in search of edible roots, etc., and to damage 
gardens and fruit orchards; they never climb trees, and hiber- 
nate in winter when they live in a cold country. 
Our American porcupines, on the contrary, are first-class 
climbers, and remain as much awake in cold weather as in 
warm, — which is no very high praise for their activity. They 
are further distinguished by the fact that the spines are shorter 
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