Western Flycatcher 273 



a. Tail even; size larger; wing about 2-70. 



a^ Above duller and more brownish ; culmen longer, about -5 ; 



lower mandible dusky. E. trailli, p. 274. 



b^ Above brighter and more greenish ; culmen shorter, about -4 ; 



lower mandible whitish. E. t. alnorum, p. 275. 



b. Tail slightly emarginate ; size much smaller ; wing about 2-55 • 



E. minimus, p. 275. 



C. Yellow wash of under-side overlaid by the extended area of the 



grey of the breast ; throat more or less grey ; tail emarginate. 



a. Tenth (outer) primary longer than the fifth ; biU small and 



narrow ; culmen about -40. E. hammondi, p. 276. 



b. Tenth (outer) primary shorter than the fifth. 



a^ Smaller; wing about 2-75; bill large; culmen -52, lower 

 mandible dark, E. wrighti, p. 277. 



b^ Larger ; wing 2-85 ; bill smaller ; culmen -50 ; lower 

 mandible pale, tipped dusky. E. griseus, p. 278. 



Western Flycatcher. Empidonax difjicilis. 



A.O.U. Checklist no 464— Colorado Records— Ridgway 73, p. 184 

 Trippe 74, p. 258 ; Henshaw 75, p. 359 ; Minot 80 ; p. 231 ; Drew 81 

 p. 140 ; Tresz 81, p. 183 ; Allen & Brewster 83, p. 195 ; Drew 85, p. 17 

 Morrison 89, p. 146 ; Kellogg 90, p. 90 ; Bendire 92, p. 298 ; Cooke 

 97, pp. 88, 209 ; Henderson 03, p. 107 ; 09, p. 233. 



Description. — Above dull oUve-brown ; wings and tail dusky brown, 

 the outer webs edged with yellowish-ohve, the middle- and greater- 

 coverts strongly tipped with greenish-brown, forming a conspicuous 

 double wing-band ; below pale primrose, soUed with buffy-olive on the 

 breast and neck, paling slightly on the throat, which is distinctly 

 yellow ; a pale yellow orbital ring ; outer (tenth) primary distinctly 

 shorter than the fifth ; tail emarginate ; iris brown, upper mandible 

 dark brown, lower pale yellowish ; legs dusky brown. Length 5-10 

 wings 2-85; tail 2-40; culmen -45; tarsus -62. 



The sexes are alike ; the young are browner above and the wing-band 

 more ochraceous. 



Distribution. — Breeding throughout the western half of North 

 America, from Alaska and western Manitoba southwards to western 

 Texas, northern Mexico and California ; in winter, south to Oaxaca 

 and Guererro in southern Mexico. 



In Colorado the AVestern Flycatcher is a regular summer resident 

 in the mountains and neighbouring foothills, breeding up to 10,000 

 feet, but not apparently in the plains. It has been recorded from Estes 

 Park, 8,000 feet (Kellogg) ; Gold Hill, breeding from 8,500 feet to 10,000 



