Gen!. Char. Rather small, general color gray. 



Color. Breeding Pelage. Above gray, sides washed with pale 

 yellowish brown, beneath grayish white. Dark dorsal stripes black 

 and rufous ; light ones ashy, outer white. 



Post-breeding Pelage. Above rufous, thighs plumbeous gra\ ; 

 dark dorsal stripes black and rufous ; outer light stripes whitish : 

 flanks yellowish rufous ; broader parts grayish white. Dark facial 

 stripes rusty brown ; light ones grayish white. Tail above black and 

 buff ; beneath buffy ochraceous bordered and fringed with black. 



Measurements. Average total length, 223 ; tail vertebra, 82 ; hind 

 foot, 31. 



a.— gracilis. {Tamias), Allen, Bull. Am. Mus. Nat. Hist.. 1890, p. 99. 



Type locality. San Pedro, New Mexico. 



Geogr. Distr. Sicorro County, New Mexico, to Apache County, 

 Arizona. 



Genl. Char. Larger than T. quadriviitatus, but more slender ; 

 tail longer, ears larger and color very different. 



Color. Post-breeding Pelage. Above light gray ; post-auricular 

 patches whitish gray. Dark dorsal stripes black ; outer part nearly 

 obsolete ; light stripes whitish gray, outer pair white. Dark facial 

 streaks bright rusty. Thighs and rump gray. Tail above black and 

 rustj', below deep orange rufous bordered with black and fringed 

 with buff. 



Measurements. Total length, 245 ; tail to end of hairs, 120 ; hind 

 foot, 34. 



b. — luteiventris. (Tamias), Allen. Am. Mus. Nat. Hist., 1890, p. loi. 



Type locality. Chief Mountain Lake, Montana. 



Geogr. Distr. Rocky Mountains in Montana from Helena north- 

 ward, probably into British America. 



Genl. Char. Similar to T. horealis, but colors much brighter : 

 body beneath buffy. 



Color. Post-breeding Pelage. Above gray mixed with rufous; 

 flanks ferruginous; ventral surface buff. Dark dorsal stripes black 

 edged with rufous. Light stripes gray and vinaceous; outer pair 

 white. Tail, above black and buff, beneath pale orange bordered with 

 black, and fringed with pale j-ellow. Upper surface of feet orange 

 buff. 



Measurenwnts. .Average total length, 243: tail vertebrif, 92: 

 hind foot, 32. 



c.—felix. [Tamias), Rhoads, Amer. Natur., 1895, p. 941. 



Type locality. Mt. Baker Range, Westminster District, British 

 Columbia. 



