546 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



outer side, or these sometimes fused into a continuous piece; middle 

 toe, without claw, usually iiuich more than half as long as tarsus, its 

 basal phalanx miited to outer toe by nearly to quite the entire length, 

 to inner toe for about half its length; outer toe, without claw, reach- 

 ing to or slightly beyond middle (falling slightly short of middle in 

 E. wriglitii) of subtermmal phalanx of middle toe, the mner toe 

 slightly shorter; hallux about as long as inner toe, decidedly stouter, 

 its claws shorter than digit (sometimes nearly as long) ; all the claws 

 moderately curved, sharp, rather larger. 



Coloration. — Above plain gray, grayish brown, buffy brown, olive 

 or olive-green, the pileum sometimes black; wings dusky with paler 

 edgings and with two more or less distinct paler bands; under parts 

 yellowish or whitish, shaded on chest and sides with gray, olive or 

 brown (one species entirely buff or oclu-aceous below), 



Nidification. — Nest open above, more or less bulky or else very 

 compact, composed of various vegetable substances and lined with 

 softer materials, and placed in trees or bushes; sometimes composed 

 outwardly of soft green mosses and placed in rocky banks near water 

 or cavities among roots of trees or logs. Eggs creamy white or buff, 

 immaculate or speckled, chiefly round larger end, with brown of 

 various hues. 



Range. — Whole of America, except West Indies and parts of South 

 America. (About thirty species and subspecies.) 



KE\^ TO THE SPECIES AND SUBSPECIES OF EMPIDONAX. " 



a. Under parts not ochraceoiis-buff. 

 b. Pileum not black or sooty. 

 c. Under tail-coverts white or pale yellow (not buffy). 

 d. Tarsus not less than 15 mm. 



e. Tenth (outermost) primary equal to or longer than lifth (sometimes longer 



than sixth). 



/. Exposed culmen longer than middle toe without claw; bill broader, its 



width at anterior end of nostrils equal to not less than half the length 



of exposed culmen. 



g. Above olive-green; wing-bands pale yellow; under parts pale yellow, 



the chest shaded with olive-green. (Eastern North America, south 



in winter to Panama.) Empidonax fiaviventris (p. 549) 



gg. Above brownish olive to greenish or grayish olive; wing-bands pale 



olive, pale grayish brown, dull whitish, or buff; under parts white, 



the chest shaded with pale brownish gray or grayish olive, the 



lateral and posterior portions sometimes tinged with pale yellow. 



h. Above greenish olive; wing-bands buff; wing and tail longer, feet 



smaller (adult male averaging wing 74.3, tail 59.3, tarsus 15.5; 



female, 70.2, 56.3, 14.8). (Eastern United States, south in winter 



to western Ecuador.) Empidonax virescens (p. 552) 



hh. Above olive (brownish rather than greenish) ; wing-])ands pale gray- 

 ish brown, pale olive, or didl whitish; wing and tail shorter, 

 feet larger. 



o Based on adults only. 



