370 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



green; under tail-coverts grayish centrally. (Northern and western Mexico 



and southern Arizona.) Cynanthus latirostris, adult male (p. 370). 



cc. Smaller, with relatively shorter bill (wing averaging 51.7, culmen 18.2), 

 back and rump bronze; chin and throat emerald green or slightly bluish 

 green; under tail-coverts dusky centrally. (Tres Marias Islands.) 



Cynanthus lawrencei (p. 373). 

 bh. Tail forked for more than one-third its length; wing, 46-51; exposed culmen, 

 16.5-19.5; forehead and crown brilliant metallic blue or bluish green. (South- 

 western Mexico.) Cynanthus doubledayi (p. 375). 



aa. Under parts brownish gray; rectrices metallic green basally, blue-black subter- 

 minally, the lateral ones tipjjed with brownish gray. (Adult females .) 

 b. Wing 49.5-54, averaging much more than 50; culmen 19-23.5, averaging much 

 more than 20; tail slightly emarginate. 

 c. Lateral under parts with little of green; basal portion of rectrices brighter 



green Cynanthus latirostris, adult female (p. 370). 



cc. Lateral imder parts conspicuously spotted or washed with metallic green; 

 basal portion of rectrices darker and duller green. 



Cynanthus lawrencei, adult female (p. 374). 

 bb. Wing 45-49, averaging 47.2; culmen 18-19.5, averaging 18.5; tail deeply emar- 

 ginate Cynanthus doubledayi, adult female (p. 375). 



CYNANTHUS LATIROSTRIS Swainson. 



BROAD-BILLED HUMMING BIRD. 



Adult male. — Above metallic bronze-green, usually duller on 

 pileiim, where sometimes passing into dull grayish brown on forehead; 

 tail glossy blue-black or dark steel blue, the four middle rectrices 

 tipped (more or less broadly) with deep brownish gray, the remaining 

 rectrices sometimes narrowly margined with the same; remiges 

 dusky brownish gray or dull slate color, faintly glossed with purplish, 

 the outermost primary narrowly edged with pale gray or grayish 

 white; chin and throat bright metallic greenisli blue or bluish green 

 (the color more blue anteriorly, more green posteriorly), passing into 

 metallic bronze-green on breast, sides, flanks, and abdomen; under 

 tail-coverts dull white, usually more or less distinctly grayish cen- 

 trally, the shorter ones sometimes with dusky, slightly metallic, spots; 

 anal tufts and tuft on each side of rump white; bill brownish (pur- 

 plish red or carmine in life), dusky terminally; iris dark brown; feet 

 dusky; length (skins), 88-105 (92); wing, 49-57 (51.6); tail, 28-36 

 (32.3), the middle rectrices 23-29.5; culmen, 18.5-22 (20.4).« 



Adult female. — Above similar in color to adult male but duller, 

 especially on pileum, which is usually dull grayish brown or brownish 

 gray anteriorly; remiges paler grayish brown; middle pair of rec- 

 trices bronze-green passing into blue-black or greenish black termi- 

 nally (the extreme tip sometimes green or bronzy); other rectrices 

 with basal half (more or less) bronze-green, the remaining portion 

 blue-black tipped with brownish gray (most broadly on lateral pair); 

 under parts sooty gray or dark drab-gray (browner than mouse gray), 



a Thirty-one specimens. 



