Vol. XXVI, pp. 135-138 May 21, 1913 



PROCEEDINGS 



OF I H E 



BIOLOGICAL SOCIETY OF WASHINGTON 



SIX NEW GROUND SQUIRRELS OF THE CITELLUS 



MOLLIS GROUP FROM IDAHO, OREGON, 



AND NEVADA. 



BY ('. HART MERRIAM. 



An examination of the large scries of Ground Squirrels of the 

 mollis group in the collection of the U. S. Biological Survey 

 indicates the existence of half a dozen apparently well marked 

 forms which hitherto have escaped recognition. Unfortunately, 

 must of the specimens were collected in late spring or early 

 slimmer, so that the seasonal pelages can not be determined 

 with certainty. In all the forms, however, there appear to be 

 two color phases — gray, and huffy or huffy fulvous. The gray 

 is commonest in adults, especially in early spring; the huffy in 

 the young when first attaining the pelage of the adult, and in 

 adults in early summer. Specimens in winter pelage, collected 

 just before the animals den up in fall, and when they first come 

 out in spring, are badly needed. 



The new forms may be known from the following descriptions: 



Citellus idahoensis sp. nov. 



Typi from Payette, at junction of Payette ami Snake River, Idaho. 

 NO. 168,290 9 ad., I'. S. Nat. Museum, Biol. Survey Coll. Collected 

 April 23, 1910, by S. <;. Jewett. Original No. 17. 



Characters. — Largest of the mollis group. Similar in general to mollis 

 bul larger, with much stronger tendency to dappling, especially in young; 

 tail longer, broader, and darker; eyelids white; anterior rim of ear 

 usually white. Skull large and massive, with outstanding and outbowed 

 zygomata. 



Color.— Gray pelage: pale hoary grayish, faintly suffused with pale 

 buffy and more or less dappled on back and rum]); end of nose dull ful- 

 vous, contrasting strongly with grizzled gray of top of head; feet soiled 

 whitish. Buffy pelage: very much darker throughout and strongly suf- 



;:;-Pkoc. Biol. Soc. Wash., Vol. XXVI. 1913. (135) 



