THE LIFE OF MAMMALS 
Merriam,** Cram,’ and in The American Naturalist for 1873 
and 1883. 
The ground squirrels are members of a group of genera well 
represented in all countries, which dwell in burrows in the 
Chip- ground instead of in holes or nests in trees, and have 
munk. acquired a trimness of form, slenderness or brevity 
of tail, and other traits, such as small close ears and eyes, strong 
claws and teeth, cheek pouches, etc., adapted to their career 
as miners. Our lively chipmunks and spermophiles, and the 
COMMON EASTERN CHIPMUNK, 
similar susliks of Russia, are good examples. Africa abounds 
in ground squirrels (genus Xerus), having a fur so harsh that in 
some species real spines are scattered among the hairs. All 
dig elaborate tunnels in the soil, in which to breed in summer 
and secrete themselves in winter, and make extensive stores of 
imperishable food upon which to subsist, hidden but not hiber- 
nating, during the months when the woods are bare and the 
ground is frozen and snowy. Thus protected from enemies 
and from famine, they are able to survive numerously even 
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