246 BULLETIN 179, UNITED STATES NATIONAL MUSEUM 



For the present, therefore, the breeding range of the present species 

 may be provisionally outlined as follows : North to Oregon (Paulina 

 Mountains and Malheur Lake) ; and northern Colorado (Majors 

 Sandwash and Mount Zirkel). East to Colorado (Mount Zirkel, 

 Hot Sulphur Spring, probably Fountain, and Bondad) ; and north- 

 eastern Arizona (Segi Canyon). South to northern Arizona (Segi 

 Canyon, Navajo County, and Grand Canyon) ; central Nevada (Arc 

 Dome and Cloverdale) ; and east-central California (Inyo County). 

 West to northeastern California (Inyo County, Mono County, Red- 

 rock, and Alturas) and central Oregon (Paulina Mountains). 



Winter range. — During winter the gray flycatcher is found north 

 to southern California (Pasadena and Furnace Creek Eanch) ; Ari- 

 zona (Rillito Creek); and Chihuahua (Chihuahua City). East to 

 Chihuahua (Chihuahua City) ; western Durango (Villa Ocampo and 

 Tamazula) ; western San Luis Potosi (San Luis Potosi) ; Guanajuato 

 (Irapuato) ; Hidalgo (Tulancingo and Irolo) ; and Puebla (Chalchi- 

 comula). South to Puebla (Chalchicomula) ; Mexico (Mexicalcingo, 

 Coapa, and Chimpalpa) ; and Jalisco (Bolanos and La Barca). West 

 to Jalisco (La Barca) ; Baja California (San Jose del Cabo, Triunfo, 

 and La Paz) ; and California (Potholes, Salton Sea, El Monte, and 

 Pasadena) . 



Spring migration. — Early dates of spring arrival are : Colorado — 

 Mack, April 24; Two Bar Ranch, April 27; Fountain, May 3. 

 Nevada — Smoky Valley, April 26. Oregon — Harney County, April 

 28. 



Fall migration. — Late dates of fall departure are : Oregon — Harney 

 County, August 29. Nevada — Toyabe Mountains, September 4 ; Santa 

 Rosa Mountains, September 9; Smoky Valley, September 11. Col- 

 orado — Escalente Hills, September 5. 



Egg dates. — Arizona: 2 records, May 29 and July 4. 



California: 46 records, June 4 to July 10; 23 records, June 7 to 

 18, indicating the height of the season. 



Colorado; 3 records. May 31 to June 4. 



Oregon: 2 records, June 7 and 15. 



EMPIDONAX DIFFICILIS DIFFICILIS Baird 



WESTERN FLYCATCHER 



PlATB 35 



HABITS 



This flycatcher was formerly called the western yellow-bellied fly- 

 catcher and was at one time treated as a subspecies of our eastern 

 flaviventris I but it is now recognized as a distinct species, as it be- 



