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TEXTBOOK OF ZOOLOGY 



form of the red squirrel. Most of these squirrels live on nuts, acorns, 

 and seeds primarily. 



The pocket gopher, of the family Geomyidae, is another burrowing 

 animal which ranges through the South, Southwest, and Midwest. 

 They are provided with strong incisors, large cheek pouches, and 

 large digging claws. They are very able diggers and construct ex- 

 tensive burrows about 12 to 18 inches below the surface. Surplus 

 earth is pushed to the surface in mounds. The cheek pouches are 

 used for gathering tubers, such as potatoes, roots, and seeds, for food. 

 The pocket mice and kangaroo rats are other related forms found in 



Fig. 337. — Banner-tail kangaroo rat, a common resident of the plains and desert. 



(Courtesy of Nature Magazine.) 



the Great Plains region and Southwest. These mice have cheek 

 pouches and long, bush-tipped tails. The kangaroo rats usually live 

 in colonies in sandy land. They build extensive tunnels. These 

 animals are built like small kangaroos with long hind legs and 

 strong tails. 



The beaver, Castor canadensis, is the largest animal of this order, 

 reaching a length of from three to three and one-half feet. At one 

 time beavers were distributed over most of North America, but now 

 they are reduced to a few in out of the way mountain streams. The 

 beaver has a stout body, strong cutting teeth, webbed hind feet, and 

 a broad, flat naked tail. It is well adapted to aquatic life and builds 



