86 Proceedings of the Biological Society of Washington. 



would indicate that the 4,500 foot contour marks their extreme western 

 limits, the center of abundance being the sandhill country of northern 

 Yuma and Phillips Counties. Their present range in Colorado may be 

 given as : — west from the Nebraska line to a point about twenty miles east 

 of Sterling, Logan Co., extending from there southeast to the Republican 

 River in Yuma County. The species seems, however, to be gradually 

 pushing westward along the river bottoms, and there is, of course, the 

 possibility of its ultimate meeting with jarnesi along the foothills, al- 

 though the great differences in their respective environments make it 

 seem decidedly improbable. It is the present writer's opinion that 

 neither Professor Cooke nor Mr. Sclater actually saw specimens of this 

 subspecies, as none of their records are from the regions it is now known 

 to inhabit, the original error of Professor Cooke (merely followed by Mr. 

 Sclater) probably being based purely upon conjecture and lack of inves- 

 tigation. 



Pedioecetes p. jamesi has evidently been the immediate cause of this 

 confusion, as many of the records already published in reality belong to 

 this form. Thus, a specimen from near the type locality at Castle Rock 

 was identified several years ago as subspecies columbianus by the Biologi- 

 cal Survey, a probable error as the separation previously outlined would 

 indicate. In addition to this separation from the western form, a long 

 stretch of totally dissimilar country lies between its easternmost records and 

 the western limits of campestris, the typical habitat of jamesi being the 

 rough, broken scrub-oak country that immediately adjoins the foothills 

 in many places on the eastern slope. 



In the northern part of the State, principally in Larimer County, sharp- 

 tailed grouse were formerly fairly numerous, as stated by Professor Cooke, 

 who assigned them to campestris. The significant fact that these birds 

 had no geographic connection with the birds of the region to the east, 

 however, was apparently passed unnoticed. Since that time the species 

 has been almost totally exterminated in Larimer County, but from the 

 scant material at hand I would unhesitatingly refer it to jamesi. 



Summarizing: columbianus occupies suitable localities west of the Con- 

 tinental Divide ; jamesi the broken country adjoining the eastern foot- 

 hills; and campestris a limited area in the prairie or sandhill country of 

 the northeast quadrant. 



