TAMIAS. 



135 



KEY TO THE SPECIES AND SUBSPECIES. 



A. Size medium. PAGE 



a. Median dark dorsal stripe alone distinct T. dorsalis 135 



b. Three dark dorsal stripes distinct; outer pair 

 faint. 



a.' Tail beneath with central area rufous T. obscurus 136 



b.' Tail beneath with central area ochraceous . . .T. bulleri 136 



c.' Tail beneath with central area- pale yellow. T. durangoe 137 

 d.' Tail beneath with central area reddish 



chestnut T. merriami 137 



c. Five dark dorsal stripes distinct T. quadrivittatus 138 



97. dorsalis (Tamias), Baird, Proc. Acad. Nat. Scien. Phil., 1855, 

 p. 332. Elliot, Syn. N. Am. Mamm., 1901, p. 68. 



quadrivittatus pallidus Coues & Yarr., in Wheeler's Rep. Geogr. 



& Geol. Expl. and Surv. West of 100 Merid., v, 1876, p. 118. 

 GILA CHIPMUNK. 



Type locality. Fort Webster, Grant County, New Mexico. 



Geogr. Distr. Northern Utah to northern Mexico; west to the 

 Sierra Nevada; east to the Mimbres in New Mexico. 



Genl. Char. Single dorsal stripe alone conspicuous. 



Color. Upper parts hoary mixed with rusty and brown; flanks 

 and hips dull rusty ; dorsal stripe dark brown ; a faint stripe of grayish 

 on flanks; under parts dull grayish white; tail above mixed black, 

 chestnut, and white, hairs chestnut at base; face with usual Tamias 

 stripes. 



Measurements. Total length, 237; tail vertebrae, 105; hind foot, 

 22; ear, 20. Skull: occipito-nasal length, 37; Hensel, 29; zygomatic 

 width, 20; interorbital width, 9; palatal length, 16; length of upper 

 molar series, 5. 



FIG. XXX. TAMIAS OBSCURUS. DUSKY CHIPMUNK. 



