3 o6 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



the constant rubbing on each other. The food of rodents is 

 chiefly vegetable. 



The order is divided into several families of which the fol- 

 lowing are the most common: the Leporidcs, the rabbits and 

 hares; the Erethizontidce, the porcupines; the Geomyidce, the 





I 



. 



I 



J 



FIG. 134. Chipmunk. (Permission of Camera Craft.) 



pocket gophers; the Zapodidce, the jumping mice; the Dipodidee, 

 the pocket mice and kangaroo rats; the Muridee, the mice and 

 rats; the Castoridtz, the beavers; and the Sciuridtz, the squir- 

 rels, woodchucks and prairie-dogs. 



Of the hares and rabbits, the cottontail, Lepus syhaticus, and 



