94 The Ohio Journal of Science [Vol. XVIII, No. 3, 



Type locality. — Cloverdale, Nye County, Nevada. 



Geographic distribution. — Western United States and extreme 

 southwestern British Columbia, south to Mexico, Central 

 America, and northwestern South America. Breeds chiefly 

 in the Lower Austral, Upper Austral, and Transition zones of 

 North America and Mexico; north to central Wyoming, central 

 Idaho, northern Washington, and southwestern British Colum- 

 bia; west to southwestern British Columbia, western Washington, 

 western Oregon,^ and western California; south to the extreme 

 northern edge of Lower California, northern Sonora, Durango, 

 southern New Mexico, and central Texas; and east to north- 

 eastern Texas, eastern Oklahoma, southeastern and central 

 Colorado. Winters from northern Colombia to Panama, 

 Costa Rica, and Nicaragua. Migrates east to eastern Nebraska, 

 Tamaulipas, and Oaxaca; west to Sinaloa and Guerrero. 



Remarks. — There is surprisingly little geographic variation 

 within the range of this race, but birds from northern Wash- 

 ington and extreme southwestern British Columbia are some- 

 what intermediate, though not sufficiently so to cause doubt 

 about their proper reference to this form. Birds from eastern 

 Colorado and Texas likewise verge somewhat toward Empidonax 

 trail Hi trailUi. 



There is, as in Empidonax traillii traiUii, a large amount of 

 individual variation in the present subspecies, including counter- 

 parts of the same six more or less well-defined color phases. 

 The two patterns of coloration on the upper parts are even 

 better indicated. In one of them the upper surface is nearly 

 or quite uniform; in the other the pileum and cervix are m^uch 

 more grayish or brownish, and distinctly, even trenchantly, 

 different from the back. The type of Empidonax traillii 

 brewsteri is of the nearly uniform style. In specimens of each 

 of these two patterns there are three definable phases of colora- 

 tion. The upper parts may in color be either (1) normally 

 dark and brownish; (2) yellowish brown on all but the pileum; or 

 (3) distinctly gray. The yellowish brown phase is not so 

 greenish as the corresponding plumage in Empidonax traillii 

 traillii, and the gray phase is very much more purely grayish, 

 less greenish. Furthermore, the lower parts are sometimes very 

 strongly tinged with yellowish, particularly on the posterior 

 portion; in other specimens this yellowish tinge is scarcely 

 noticeable, except on the crissum. 



