212 Proceedings of the Biological Society of Washington. 



Measurements. — Type: Total length, 337; tail vertebrae, 100; hind foot, 

 47. Average of 9 adults from Ruby Valley and Skelton, Nevada, and 

 McDermitt, Oregon: Total length, 291.1 (270-307); tail vertebrae, 88.1 

 (76-100); hind foot, 46.1 (42-48). Sfcuii.— Average of 5 adults (3 males, 

 2 females) from Paradise and Metropolis, Nevada: Greatest length, 47.6 

 (44.7-48.6); zygomatic breadth, 31.5 (29.9-32.4); breadth of cranium, 

 21.1 (19.8-21.7); least interorbital breadth, 10.1 (9.2-11.6); least postorbi- 

 tal breadth, 10.8 (10.4-11.5); length of nasals, 17.7 (17-18.6); maxillary 



tooth row, 9.7 (9.3-10.3). Skvll of type: 48.6; 32.2; 21.4; ; 10.5; 



18.6; 10.3. 



Range. — Northeastern Nevada and southeastern Oregon; specimen 

 examined from McDermitt and head of Quinn River, Oregon; Paradise 

 Valley, Mountain City, Metropolis, Elko, Skelton, and Ruby Valley, 

 Nevada. 



Citellus columbianus ruflcaudus, subsp. nov. 



BLUE MOUNTAINS GROUND SQUIRREL. 



Type. — Female adult, skin and skull. No. 231,942, U. S. National 

 Museum (Biological Survey collection); collected at Wallowa Lake, 

 WaUowa County, Oregon; by George G. CantweU; original number 1093. 



Svhspeeific characters. — Similar to Citellus c. columbianus, but sides of face 

 and usually the throat a deeper shade of tawny; legs and feet darker; upper 

 side of tail tawny (instead of gray) ; hind feet and skull larger. 



Measurements. — -Average of 10 adults (8 males, 2 females) from Wallowa 

 Mountains, Enterprise, Elgin, and Bourne, Oregon: Total length, 369.6 

 (340-410); tail vertebrae, 100.7 (80-115); hind foot, 54.2 (51-58). Skull. 

 — ^Average of 8 males from same locaHties: Greatest length, 54.2 (51.5-57); 

 palatal length, 26.6 (24.5-28); zygomatic breadth, 34.1 (33.2-35.6); 

 breadth of cranium, 21.9 (21.6-22.4); least interorbital breadth, 12.4 

 (11.1-14.3); least postorbital breadth, 11.9 (10.5-12.6); length of nasals 

 19.8 (18.8-20.3); maxillary tooth row, 11.4 (10.5-12.4). Skulloftype (9) 

 52.8; 25.5; 34.1; 21.7; 13; 12.2; 19.1; 11. 



Range. — The Blue Mountain region of northeastern Oregon and south- 

 eastern Washington. Specimens have been examined from the following 

 localities: 



Washington: Anatone; Blue Mountains, 20-30 miles southeast of Dajrton. 

 Oregon: Austin; Anthony; Bourne; Cornucopia; Dixie Butte; Elgin; 

 Enterprise; Meacham; Wallowa Lake. 



Citellus spilosoma pallescens, subsp. nov. 



Type.— Male adult, skin and skuU, No. 79,535, U. S. National Museum 

 (Biological Survey collection); collected at La Ventura, Coahuila, Mexico, 

 August 10, 1896, by E. W. Nelson and E. A. Goldman; original number, 

 10,016. 



Subspecific characters. — Similar to Citellus s. spilosoma (as represented by 

 specimens from Durango), but paler; skull smaller, with shorter, broader 

 rostrum. Compared with Citellus s. canescens, of Arizona; Size larger; tail 



