354 



BRANCH CHORDATA 



Jumping-mice (Dipod'idce) (Fig. 287) arc represented by the American 

 jumping mice and the Palaearctic Jerboas. They have long tails and the 

 hind legs are greatly elongated and adapted for taking enormous leaps. 



Fig. 286. Lombardy poplar killed by field mice. (Farmer's Bulletin 

 No. 335, U. S. Dept, of Agriculture, October, 1908.) 



Fig. 287. Jumping mouse. (After Tenney.) 



The pouched gophers (Geomy'idce) have large cheek pouches opening ex- 

 ternally (Fig. 288, a, b, c). These burrowing rodents are restricted to Cen- 

 tral America and the central plains of North America. They have small ears 

 and eyes. The claws of the anterior limbs are strong. 



