500 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



i. Smaller (wing averaging 63.3, tail 47.8). (Southwestern border 

 of Ignited States, from western Texas to Arizona, and south- 

 ward into northwestern INIexii-o.) 



Dendroica aestiva sonorana, adult niale (]>. 512) 

 //. Larger ( wing averaging (iS, tail 5;!). (Central ^lexico. ) 



Dendroica aestiva dugesi, adult male (j). 5115) 

 gg. Smaller (wing averaging less than 62, tail averaging less than 4i>) 

 and duller colored; pileum alway.s olive-green, like baek, rarely 

 becoming yellowish on forehead; wing-coverts and tertials nar- 

 rowly edged with yellowish olive-gveen or olive-yellow; back, etc., 

 darker olive-green. (Vancouver Island to Alaska in summer, south 

 to southern California, central Texas, and Nicaragua in Avinter. ) 

 Dendroica aestiva rnbiginosa, adult male (p. 514) 

 ee. Wing more rounded, the outermost (ninth) primary decidedly shorter 

 than sixth; tarsus longer, very rarely less than 20, averaging 20.9; 

 tail relatively longer, averaging al)out 48.5; West Indian.' 

 /. Larger (wing of adult male usually more than 60, averaging more than 

 61); pileum without a distinct patch of tawny, chestnut-tawny, or 

 chestnut, or else wing 62 or more, averaging 65.4. {Dendroica 

 petechia.) 

 g. Pileum without a distinct patch of orange-ochraceous or tawny, or 

 if pronouncedly thus colored the color not sharply defined nor 

 strongly contrasted laterally against the yellow of the supen-iliary 

 region; wing averaging not more than 65, usually much less. 

 /(. Lighter, brighter, more yellowish olive-green alwve; the pileum 

 usually more or less tinged with yellow, ochraceous, or tawny, 

 sometimes mostly thus colored; yellowish wing-markings more 

 distinct, more decidedly yellow; yellow of under parts deeper. 

 i. Yellow of under parts less intense and chestnut streaks on chest 

 and sides narrower or fewer. 

 j. Wing longer (averaging 65) and bill smaller (exposed culmen 

 averaging 10.6). (Island of Jamaica; Haiti?). 



Dendroica petechia petechia, adult male (p. 515) 

 jj. Wing shorter (averaging 61.4) and bill larger (exposed culmen 

 averaging 11.1). (Island of Grand Cayman.) 



Dendroica petechia auricapilla, adult male (p. 517) 

 ii. Yellow of under parts more intense, and chestnut streaks on 

 chest and sides heavier or more numerous. 

 j. Smaller (wing averaging 61, tail 47.9, exposed culmen 11, tarsus 

 20.5) ; chestnut streaks on chest and sides averaging narrower; 

 crown more rarely tinged with ochracef)US or tawny. (Baha- 

 mas.) Dendroica petechia flaviceps, adult male (p. 517) 



jj. Larger (wing averaging 62.3, tail 49.1, exposed culmen 11.3, 

 tarsus 21.3); chestnut streaks on chest and sides averaging 

 heavier; crown more often tinged with ochraceous ortawiiy. 

 (Islands of Porto Rico, Vieques, St. Thomas, Virgin Gorda, 

 Anegada, St. Croix, Anguilla, St. Bartholomew, St. Eustatius, 

 St. Christopher?, Barbuda, and Antigua. ) 



Dendroica petechia bartholemica, adult male (}>. 518) 



hh. Darker and duller olive-green above, the pileum usually concolor 



with back, or nearly so (rarely distinctly tinged with yellow. 



' Except one form on Cozumel Island, Yucatan, and one from the Galapagos Archi- 

 pelago, Cocos Island, and contiguous coast of South America. 



