Vol. 31, pp. 31-32, 1918 May 16, 1918 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



A NEW SUBSPECIES OF CHIPMUNK FROM THE YEL- 

 LOWSTONE NATIONAL PARK. 



BY VERNON BAILEY. 



In the list of mammals of the Yellowstone Park in the 1917 

 Circular of Information,* I referred the little gray sagebrush 

 chipmunk of the open valley about Swan Lake to Eutamias 

 minimus pictus (Allen), basing my provisional identification on 

 the animals seen alive and running through the sagebrush. On 

 visiting the park again in September, 1917, I explained to Mr. 

 Chester A. Lindsey, Acting Supervisor of the Park, the neces- 

 sity of obtaining a few specimens of these chipmunks for identi- 

 fication and was granted a permit for taking such as were needed. 

 On making a critical comparison of these specimens with others 

 in the National Museum Collection I find that while they closely 

 resemble the little gray pictus of the Great Basin country they 

 are in reality a pale gray form of E. consobrinus which occupies 

 the higher country of the Park and mountain ranges to the 

 southward, and that they can not be referred to any form at 

 present recognized. They may be known by the following de- 

 scription: 



Eutamias consobrinus clarus, subsp. nov. 



Type from Swan Lake Valley, Yellowstone National Park; adult <?, 

 No. 227313, U. S. National Museum, Biological Survey Collection. Col- 

 lected by Vernon Bailey, September 13, 1917; original number 9945. 



Characters. — A small slender chipmunk, paler and grayer than conso- 

 brinus, but with the same fulvous under surface of tail. Size of consobrinus , 

 but colors paler and clearer gray with much less fulvous on sides and 

 upperparts. Under surface of tail rich fulvous, almost as dark as in 



•General Information regarding Yellowstone National Park, Department of the 

 Interior, Season of 1917. Mammals by Vernon Bailey, pp. 44-54. 



8— Proc. Biol. Soc. Wash.. Vol. 31, 1918. (31) 



