FAMILY TYRANNIDAE 361 



51. Crest more prominent, pointed, with a definite white stripe in center; 



abdomen somewhat brighter yellow. 



Yellow-bellied elaenia, Elaenia flavogaster, p. 555 



Crest less evident, with white restricted in amount or absent ; somewhat 



duller yellow on the abdomen 52 



52. Slightly larger (average male, wing 80.9, tail 71.2 ; female, wing 75.1, tail 



66.1 mm.); white on tertials somewhat more extensive; no white in 

 crown, or if present, much reduced. 



Mountain elaenia, Elaenia jrantzii frantsii, p. 549 

 Slightly smaller, more slender (average male, wing 74.2, tail 62.3 ; female, 

 wing 67.8, tail 56.6 mm.); white in tertials less in amount; white in 

 crown reduced, usually completely hidden. 



Lesser elaenia, Elaenia chiriquensis chiriquensis, p. 552 



53. Darker, dusky above, with crown and tail averaging blacker than back ; 



throat and abdomen white, somewhat grayish white to faintly yellowish 



white, or slightly buffy 54 



Slightly brownish to faintly greenish olive above, with crown and tail 

 generally similar, but in some these areas slightly darker than the back ; 

 throat and abdomen white to grayish white, or in some yellowish 57 



54. Averaging larger, length 135-145 mm; dorsal surface less blackish, with 



crown, back, and tail more uniform in hue 55 



Averaging smaller, more slender, length 120-135 mm, with crown and 

 tail distinctly blacker than back 56 



55. Above more greenish olive; axillars and under wing coverts white to 



pale grayish brown edged with white; longest upper tail covert shorter, 

 with distance from its tip to end of tail greater, in males 33.9-36.8; in 

 females 32.0-35.5 mm ; mandible dull white to pale buff, with only the tip 



darker Eastern wood pewee, Contopus virens, p. 452 



Above darker, more olive ; axillars and under wing coverts gray to brown, 

 varying in shade but without white ; distance from tip of longest upper 

 tail coverts to end of tail less, in males 29.9-32.6, in females 27.8-32.6 mm ; 

 most of mandible darker, blacker. 



Western wood pewee, Contopus sordiduhis, p. 455 



56. Loral area grayish white ; white eye-ring indistinct ; throat and abdomen 



white to very pale yellowish ; larger, length 120-135 mm. 



Tropical pewee, Contopus cinereus, p. 459 

 Loral area indistinctly grayish ; white eye-ring wider, especially around back 

 of eye ; much smaller, length 105-115 mm. 



Black-capped flycatcher, Empidonax atriceps, p. 466 



57. Axillars and under wing coverts distinctly buff to cinnamon-buff.-* 58 



Axillars and under wing coverts white to pale yellow, not buff 59 



58. Distinctly reddish brown to buffy brown above; breast and sides heavily 



streaked with dusky. 



Bran-colored flycatcher, Myiophobus jasciatus furfurosus. p. 494 

 Olive-brown above ; breast and sides not heavily streaked. 



White-throated flycatcher, Empidonax albigiilaris australis, p. 471 



• Some juvenile Empidonax minimus have the carpal edge of the wing and the 

 axillars pale buff, in addition to this color on the wing bands. 



