Vol. XXVI, pp. 9-12 January 18, 1913 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



ADDITIONAL NOTES ON THE DISTRIBUTION OF 

 COLORADO MAMMALS. 



BY EDWARD K. WARREN. 



Two collecting trips which I made in Colorado in l'.>12 yielded 

 some rather interesting data on the distribution of certain Colo- 

 rado mammals. The first of these expeditions was in April and 

 May, when I collected at Mack, Mesa County, about ten miles 

 east of the Utah line, at an altitude of 4540 feet, in an arid, desert 

 region; at Atehee, Garfield County, about thirty miles northerly 

 from Mack, on the Uintah Railway, on the southern slope of 

 the Book Plateau, at 6340 feet; at the Sieber Ranch on Little 

 Dolores Creek, Mesa County, some twenty miles westerly from 

 Grand Junction, and six miles east of the Utah line, at 5675 

 feet. This last point was selected because to some extent it 

 helped fill up the gap between the work done by Merritt Cary 

 on the Dolores River to the South, and that done on the Grand 

 River to the north. It was in a valley, sometimes quite narrow 

 and again opening out into quite wide level spaces, always with 

 rather high red sandstone walls on either side. 



My second expedition was to San Acaeio, in southern Costilla 

 County, in a part of the San Luis Valley where no collecting 

 had previously been done. This was a level prairie region, the 

 altitude of the town being 7740 feet. Culebra Creek is a little 

 south of the town and the northwesterly extension of the San 

 Luis Hills is about three miles west. The Culebra Range, with 

 some high, rugged peaks, is twenty miles to the eastward. I 

 made a week's trip to Culebra Canon in this range. I also did 

 a few days' work at Blanca, sixteen miles north of San Acaeio. 

 My Costilla County collecting was done the last of June and 

 first three weeks of July. 



3— PRQC. Bipj .. SOI V \W- Vo|.. XXVI. 1913. (9) 



