1324 



THE RODENTS 



often forming a large proportion of its contents. The food is said to be carried tc* 

 this storehouse in the capacious cheek pouches of the animal. Usually the pocket 

 gopher works at its tunnels or domicile from about four to ten o'clock in the morn- 

 ing, during which time it excavates from twelve to twenty feet of tunneling, and 

 will throw up from two to five hillocks. Other species of pocket gophers belonging 

 to this genus are found in the Southern United States, Mexico, and Central 

 America. 



The northern pocket gopher ( Thomomys talpoides) is the best- 

 known representative of the second genus, containing at least two spe- 

 cies, and distinguished by the absence of grooves in the upper incisor 

 teeth. This species measures from six to eight inches in length, and 

 the tail some three inches more; while its general color is very similar to that of the 



Northern 

 Pocket 

 Gopher 



THE COMMON KANGAROO RAT. 



(One-half natural size.) 



brown rat. The animals of this genus are distributed over the whole of Canada and" 

 North America west of the Rocky mountains. In habits they precisely resemble 

 the preceding genus. 



THE KANGAROO RATS 

 Genus Dipodomys 



The kangaroo rats and their smaller allies the pocket mice are utterly unlike 

 the pocket gophers in external appearance, having elongated hind-limbs and tails, 

 large eyes, and well-developed ears, while their habits resemble those of the jerboas. 

 They agree, however, with the former in the possession of large external cheek 



