504 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



U. Throat and chest only partly black. 



Deudroica virens, adult female (p. 562) 

 kk. Pileum and back plain black or streaked olive-green and 

 black; breast and abdomen pure white. 



I. Pileum and back uniform black; throat and chest uniform 



black. (Texas to Guatemala. ) 



Dendroica chrysoparia, adult male (p. 565) 



II. Pileum and back streaked olive-green and black; throat 



and chest (usually) only partly black. 



Dendroica chrysoparia, adult female 

 and immature male (p. 566) 

 jj. No black, dusky, or olive postocular streak, the sides of head 

 entirely yellow; back and rump gray, the former streaked 

 or spotted with black; black of chest with convex posterior 

 outline; pileum at least partly yellow. (Western United 

 States and British Columbia, south to Guatemala in winter.) 

 Dendroica occidentalis, adult male (p. 567) 

 hh. Throat without any black. 

 i. Wing with two distinct bands (across tips of middle and greater 

 coverts, respectively) of white, yellowish, or pale gray — or else 

 with these coalesced into a single large patch. 

 j. Upper parts light grayish blue. (Eastern United States; south 

 in winter to northern South America. ) 



Dendroica rara, adult male (p. 570) 

 jj. Upper parts not light grayish blue. 



k. A superciliary stripe of white, yellow, or buff. 



I. Throat white or pale olive-yellowish; sides of head without 



yellow.' 

 m. Back and auricular region greenish or bluish; no yellow 

 supraloral spot. 



Dendroica rara, adult female and 

 immature male (p. 570) 

 7nm. Back and auricular region brownish gray or grayish 

 brown; a small yellow supraloral spot. 



Dendroica nigrescens, immature female (p. 557) 



II. Throat yellow, orange, or buff, or else sides of head mostly 



yellow. 

 m. Sides of head mostly yellow; throat not wholly yellow, 

 orange, or buff. 

 n. Back olive-green; feathers of pileum dusky basally. 



Dendroica virens, immature female (p. 562) 

 nn. Back grayish; feathers of pileum yellow basally. 



Dendroica occidentalis, immature female (p. 568) 

 mm. Sides of head not mostly yellow; throat wholly yel- 

 low, orange, or buff. 

 n. Back neither gray nor plain grayish brown. 

 0. Back olive-green. 



Dendroica townsendi, immature female (p. 560) 

 00. Back not olive-green. 

 p. Back black with a whitish or yellowish stripe along 

 each side; throat orange. 



Dendroica blackburnise, adult male (p. 574) 

 pp. Back not black ; throat not orange. 



' Except, in D. nigrescens, a small supraloral spot. 



