338 



VERTEBRATE AXIMALS OF THE UXITED STATES 



0. g. juglans (Bailey). Color brownish gray; length 500 mm.; tail 

 225 mm.: Mogollon Mountains, New Mexico. 



7. Citellus Oken. {S pernio philus Cuvier). Ground squirrels; 

 gophers. Small body and slender; cheek-pouches large; thumb rudi- 

 mentary (Fig. 182); dentition i/i, 0/0, 2/1, 3/3: about 80 species, 

 mostly in the more or less arid regions of northern and western America, 

 northern Asia and Europe : over 50 species and subspecies in the United 

 States and Canada. Ground squirrels feed on grains, seeds, fruits, 

 plants, etc. and are very destructive to crops; they also often eat insects 

 and other small animals. They breed in deep burrows, 

 in which they raise from 5 to 13 young in a litter, 

 and usually one litter a year. In the more northerly 

 latitudes they hibernate in the winter, often 6 or 

 more months, but in warmer regions may remain 

 active throughout the year. 



C tridecemlineatus (Mitchill). Gopher. Color 

 yellowish-brown, with about 6 yellowish longitudinal 

 stripes alternating with rows of yellow spots, making 

 about 13 stripes in all; belly yellowish; ears small; 

 length 275 mm.; tail 107 mm.; hind foot 32 mm.: 

 central States, from eastern Michigan to the Rockies; 

 Fig. 182.— Fore southward to northern Missouri and central Texas; 



foot of Citellus oil • 1 !• 



spiiosoma {from northward mto Saskatchewan ; a smgle litter of young 

 ^"'''''^- raised a year. 



Subspecies of C. tridecemlineatus 



C. t. tridecemlineatus (Mitch.). Southern Michigan to Dakota. 



C. /. alleni (Merriam). Size small; colors dark: Bighorn ^Mountains, 

 Wyoming. 



C. t. parvus (Allen). Size small; length 204 mm.: southeastern 

 Montana to western Colorado, Wyoming and Utah; Upper Sonoran zone. 



C. t. pallidus (Allen). Size small; colors pale: Great Plains from 

 eastern Montana and western Dakota into northeastern Utah and 

 northern Colorado. 



C. t. olivaceus (Allen). Color dusky brown above: Black Hills. 



C. t. hadius (Bangs). Size large; length 276 mm.; colors dark: 

 Missouri and Oklahoma. 



C. t. texensis (Merr.). Size large; color deep ferruginous: eastern 

 Texas and Oklahoma. 



C. franklini (Sabine). Body yellowish brown, speckled with 

 black but not striped; tail with 3 black lines; length 375 mm.; tail 137 



