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species build so many in the forks of trees, being used only as tem- 
porary summer-houses. This Squirrel is not known to migrate in com- 
panies; they sometimes cross open country, like other Squirrels, in 
search of food. 
It is the shyest of our species; if chased it dees not stop on branches 
or take to the nearest tree, but runs at once to its hole. They are ex- 
tremely active, rarely lying lazily sunning themselves, as does the Gray 
Squirrel. Their long bushy tails are in constant motion, as they spring 
from limb te limb apparently for mere sport. 
Genus Tamras Illiger. 
Sciwrus, in part, of most early authors. 
Zamias, Illiger, Syst. Mamm. et Avium, 1811, 83 (type Sceurus striatus, 
Linneeus). 
Zenotts, Rafinesque, Amer. Month. Mag., i, 1817, 362. 
Generic Characters—Skull narrowed anteriorly; postorbital processes 
tong, very slender, directed downward and backward; plane of malar 
bone more oblique, and zygomatic process of maxillary more expanded 
and depressed than in Scturus, but rather less so than in Spermophilus ; 
anteorbital foramen oval, situated in the base of the zygomatic process 
of the maxillary; upper premolars two or one—when two, the first usually 
minute; ears of medium size or small, well clothed, but never tufted; 
cheek pouches large ; Race with a well developed nail ; tail shorter than 
the body, flattened and rather broad, shorter and much narrower than in 
Scowrus; pelage generally full and soft; dorsal surface with two (usually 
four) longitudinal whitish stripes bordered on each side with a stripe of 
black, and with, except in one species, a central dorsal stripe of black, 
known from the smaller species of Spermophilus by the absence or 
rudimentary character of first upper premolar; weaker and relatively 
smaller dentition; more delicate and papery skull and more flattened 
tail; known from Chinas by the more slender lower jaw, capacious cheek 
pouches, and shorter and narrower tail. . 
As above defined, Zamzas includes four species, 7. striatus, I. asiaticus, 
with several localized sub-species, 7. harvest, and YT. lateralis. All are 
confined to North America except asiaticus, which ranges also over a 
large part of northern Asia and eastern Hurope. 
TAMIAS STRIATUS (Linn.) Baird. 
STRIPED GROUND SQUIRREL; CHIPPING SQUIRREL; CHIPMUNK; also CHIPMOCK. 
1731. Sciurus strietus, Catesby, Carol., 11, 1731, 75, pl. lIxxv.—Linnzus, 
Syst. Nat., 1758, 64.—Schreb., Siug., iv, 1791, 791.—HErxleben, 
