1936] 



MAMMALS OF OREGON 



139 



Econonvic status. Except very locally these little chipmunks are 

 not destructive to crops, but their consumption of seeds of grass and 

 other useful plants may have considerable influence on abundance of 

 vegetation in the arid valleys where they live. Their consumption 

 of insects must partly, or may wholly, compensate this loss of vege- 

 tation. A closer study of food habits is necessary to decide the 

 balance of account for or against them. 



CALLOSPERMOPHILUS CHRYSODEIRUS CHRYSODEIRUS (MEERIAM) 



GOLDEN-MANTLED GROUND SQUIRREL; YELLOW HEAD; CALICO SQUIRREL; CHIL-LAS 

 of the Klamath (C. H. M.) ; WO-TAH of the Piute at Burns 



Tamias chrysodeirus Merriam, North Amer. Fauna No. 4, p. 19, 1890. 



Type Collected at Fort Klamath, Oreg., by Samuel Parker, in 1888. 



General characters. Larger and heavier than the true chipmunks; ears 

 prominent ; tail moderately bushy ; feet large with naked soles and palms ; toes 

 5 on each foot, thumb a mere rudiment; mammae in 4 pairs 1 inguinal, 2 

 abdominal, and 1 pectoral ; in- 

 ternal cheek pouches ample. 

 Summer pelage, sides of back 

 with 4 black and 2 white or 

 buffy stripes ; middle of back, 

 rump, and hams rusty gray; 

 shoulders, neck, cheeks, arms, 

 and lower surface of tail, 

 bright ochraceous tawny; 

 crown hazel ; lower parts and 

 feet buffy gray, or dull ochra- 

 ceous; upper surface of tail 

 black, washed with pal 

 ochraceous. Young, as in 

 summer adults. Winter pel- 

 age with the same black and 

 whitish stripes but without 

 the golden mantle and with 

 general coloration much dul- 

 ler and grayer; lower surface 

 of tail as in summer. 



Measurements. Average of 

 five adults: Total length, 258 

 mm; tail, 90; foot, 40; ear (dry), 15. 

 (Grinnell and Storer, 1924, P- -*73). 



Distribution and habitat. This ground squirrel is one of the most 

 widely ranging forms of the genus, showing only slight variation 

 from the southern Sierra Nevada Mountains of California north to 

 Mount Hood and the Columbia River in Oregon, and from the west- 

 ern slopes of the Sierra Nevadas and Cascades east through most of 

 the mountain ranges of Nevada, eastern Oregon, and into southern 

 Idaho (fig. 24). Apparently the Columbia Eiver Canyon is sufficient 

 barrier on the north to separate them sharply from Cattospermopki- 

 Lus lateralis saturates of the Cascades of Washington, while the 

 Snake River Canyon on the east separates them as sharply from C. I. 

 cinerascens of central Idaho. 



Their principal range is in Transition and Canadian Zones, but in 

 places they reach up into Hudsonian and in other places down into 

 Upper Sonoran Zone. Generally they inhabit the timber, but in the 

 edges of the valleys come down along lines of rocky cliffs and ledges 

 where they find safe cover among the rocks and ample food supply 

 from the bushes and small plants. 



FIGURE 24. Range of two forms of Callospermo- 

 philus in Oregon : 1, Callospcrmophilus chrysodei- 

 rus chrysodeirus ; 2, C. c. trinitatis. Type locality 

 circled. 



Weight: 135 to 239 g (4% to 8V 2 ounces) 



