FIELD BOOK OF MAMMALS 



Colorado Chipmunk. — Eutamias minimus operarius (Merriam). 

 Very similar to consobrinus and also somewhat resembling 

 typical amoenus. Dorsal stripes broad and conspicuous; 

 inner dark stripes blackish, outer pair blackish, mixed with 

 rufous; inner light stripes grizzled gray, outer pair white; 

 rest of upperparts mixed gray, blackish and fulvous; sides 

 washed with fulvous; small ear patch gray; tail below, 

 rufous, fringed with ochraceous buff. Easily confused with 

 quadrivittaius from which it may be distinguished by smaller 

 size, proportionally longer tail and grayish rump. Total 

 length, 8 inches; tail vertebrae, 3.7 inches; hind foot, 1.24 

 inches. Found in Colorado; chiefly east of Continental 

 Divide from foothills to timber-line. 



Sacramento Mountain Chipmunk. — Eutamias minimus atri- 

 striatus (Bailey). 

 Resembling operarius but somewhat larger and darker. 

 Dorsal stripes broad, five black stripes, two rusty and two 

 buffy whitish; sides dull grayish fulvous; abdomen with 

 yellowish tinge. Total length, 8.5 inches; tail vertebras, 3.8 

 inches; hind foot, 1.28 inches. Found in the Sacramento 

 Mountains, Lincoln County, New Mexico. 



Arizona Chipmunk. — Eutamias minimus arizonensis Howell. 

 " Similar in size and cranial characters to Eutamias minimus 

 atristriatus ; nearest in color to E. minimus consobrinus, but 

 general tone more grayish (less tawny), the shoulders fre- 

 quently washed with pale smoke-gray (as in Eutamias 

 cinereicollis) ; tail more bushy and color of undersurface 

 brighter tawny (about as in operarius) .'^ (Howell) Total 

 length, 8 inches; tail vertebrae, 3.8 inches; hind foot, 1.2 

 inches. Found in the White Mountains and Prieto Plateau 

 of eastern Arizona. 



Timber-line Chipmunk. — Eutamias minimus oreocetes (Mer- 

 riam) . 

 In spring pelage, somewhat resembling typical minimus. 

 Upperparts gray, washed with buffy yellow on sides of neck 

 and body; ear patch whitish; mid-dorsal stripe black, outer 

 dark dorsal stripes blackish and rusty; inner light stripes 

 whitish, outer white; feet whitish; tail below, pale fulvous, 

 banded with black, edged with ochraceous buff. Total 

 length, 8 inches; tail vertebrae, 3.6 inches; hind foot, 1.24 

 inches. Found near timber-line in mountains of Montana 

 and Wyoming. 



Northern Chipmunk. — Eutamias minimus boreal is (Allen). 

 About the size of typical minimus but darker in color. 

 Upperparts mixed tawny, and gray; sides clear tawny, 

 median stripe blackish, other four dark stripes dark brown 

 to blackish, mixed with rufous; inner light stripes grizzled 

 gray, outer white; tail below, ochraceous, fringed with 

 ochraceous buff; underparts white, with light buffy tinge 

 in some specimens. Total length, 8.2 inches; tail vertebras, 

 3.8 inches; hind foot, 1.28 inches. Found in forests, east 



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