Vol. 33, pp. 91-92 December 30, 1920 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



DESCRIPTION OF A NEW CHIPMUNK FROM GLACIER 

 NATIONAL PARK, MONTANA. 



BY ARTHUR H. HOWELL. 



Faunal studies of the chipmunks of Montana have shown 

 the necessity for recognizing an undescribed species of Eutamias 

 from the eastern slopes of the main Rocky Mountain divide, 

 specimens of which have been in the Biological Survey collection 

 for many years. It may be described as follows: 



Eutamias ruficaudus, sp. nov. Rufous-tailed Chipmunk. 



Type. — No. 72294, U. S. National Museum, Biological Survey Collec- 

 tion; adult male, skin and skull; from Upper St. Mary's Lake, Montana; 

 collected May 30, 1895, by A. H. Howell; original number 27. 



Specific characters. — Similar to Eutamias umbrinus, but coloration de- 

 cidedly more rufescent; head and face more tawny (lrss grayish); dorsal 

 stripes and spots behind ears less whitish; under side of tail deeper reddish. 



Description of type (unworn winter pelage). — Sides of nose cinnamon; 

 top of head and face, cinnamon, mixed with grayish white and bordered 

 with fuscous; stripe from tip of nose above the eye to anterior base of ear 

 and another beneath the eye to posterior base of ear buffy white, these 

 light stripes bordered on each side with fuscous stripes mixed with tawny 

 (the median one in front of and behind the eye) ; ears fuscous, with a rather 

 broad band of pinkish buff on posterior margin ; inside of ear clothed with 

 tawny hairs; median dorsal stripe (extending from crown to root of tail) 

 and lateral pair of dark stripes black or fuscous black, slightly mixed with 

 tawny; alternate dorsal stripes (four in number) grayish white, mixed 

 with tawny, the median pair shading anteriorly into the color of the 

 crown, the outer pair bordered beneath with an indistinct stripe of fuscous 

 black; sides of body deep tawny; thighs and rump mixed cinnamon and 

 grayish white, producing a drabby tone; fore- and hind-feet pinkish cin- 

 namon, the toes washed with pinkish buff; underparts grayish white, 

 faintly washed with pale pinkish buff; under side of tail, Sanford brown, 



19— Proc. Biol. Soc. Wash., Vou 33, 1920. (91) 



