258 



MAMMALS OF AMERICA 



The Pocket Mouse is a peculiar and interest- 

 ing little fellow, whose nearest relative is the 

 Pocket Rat, or Kangaroo Rat. The latter, in 

 fact, may be called his big brother, so closely 

 do they resemble each other. The Pocket Mouse 

 belongs to a different family from the Meadow 

 Mice and \\'hite-footed Mice, and may be easily 

 distinguished from others by the external cheek 

 pockets. Nearly all members of this group 

 live in the desert or arid plains, and they are 

 most numerous in the Southwest. 



Few persons are at all familiar with this little 

 rodent, and when one mentions the fact that 



homes in the interstices of rocks. In Texas, 

 Merritt Cary caught one under a pile of rocks 

 at the east base of the Davis Mountains at an 

 altitude of about 5000 feet. Speaking of the 

 Ycllo^i' Pocket Mouse. \'ernon Bailey savs: 

 " At El Paso these little Yellow Pocket Mice 

 were common in December, along the edges of 

 the sandy valley bottom two miles below town, 

 where little sand drifts were heaped up around 

 the base of Atriplcx and Siiacda bushes. Their 

 burrows were usually in groups of three or four, 

 under the edges of the bushes. The occupied 

 ones were closed, and were discovered only by 



Photograph by U. S. Biological burvey 



POCKET MOUSE 



Although very numerous in some localities, it is surprising how few people know about the remarkable 

 features which differentiate these from ordinary mice 



there are a half hundred species of these odd- 

 looking little creatures, the surprise of the 

 listener grows apace. \\"\\.\\ the exception of the 

 Pocket Gophers and the Junijiing Mice, the 

 Pocket Mice and Rats are the only North Ameri- 

 can mammals that have the pouches which give 

 them their name. These serviceable receptacles, 

 which are placed in the skin of each cheek, are 

 hair-lined, have somewhat narrow openings, and 

 extend back almost to the ears. In them their 

 possessors carry seeds and berries of various 

 kinds, often stuffing the pockets quite full. 



Most of the species are inhabitants of the 

 plains and the prairies, but a few make their 



following the lines of tiny footprints across the 

 bare patches of sand from bush to bush, till 

 they disappeared at little mounds of fresh earth 

 that served as doors and blinds to the under- 

 ground houses. By scraping away the earth, a 

 burrow big enough to admit a little finger was 

 disclosed under each tiny mound. On chilly 

 nights they did not move about much, but on 

 mornings following a warm night their lines of 

 tracks were abundant. One specimen caught 

 December 15. was apparently nursing young." 

 All of the species are nocturnal, and. as far 

 as known, none of them hibernate. ^^l^en 

 caught, " they do not offer to bite, but sometimes 



