108 ANIMAL COMPETITORS 
presence affects humanity in a very trifling de- 
gree. 
The only representative in the Hast is the 
common tawny-red, large-eared jJumping-mouse, 
often seen rushing away from under foot in 
amazing leaps. The hind legs and feet are 
tremendously developed, while the fore pair are 
exceedingly small and delicate. The nose is 
pointed, and the hairless tail very long, meas- 
uring 5 inches from root to tip, while the 
length of the body is only 3 inches. They sub- 
sist almost exclusively on weed-seeds, and go 
early to bed in warm grass-nests underground, 
where they remain in deep hibernation until 
late in the spring. 
In the arid West and in Mexico live numer- 
ous small cousins of the genus Perognathus, 
whose hind legs are less lengthened, and which 
have fur-lined pockets in their cheeks, tiny 
ears, gray or yellowish coats, pure white feet 
and under parts, and tails about the length of 
their bodies. They are rarely seen, because 
nocturnal; burrow in dry ground; and lay up 
stores of small seeds. They are easily caught 
in small traps baited with rolled oats (of which 
