BLACK- THROATED BLUE WARBLEK. 



19 



Male. Above, dusky blue, occasionally spotted with black. White 

 beneath, with throat and line along sides, black. Wings and tail very dark 

 brown, with each feather margined externally with bluish. Base of all but 

 outer and inner primaries white, forming a conspicvious patch, and all the 

 secondaries are margined with white. The outer tail feathers are spotted on 

 inner webs with white, each feather being surrounded by a smaller spot, 

 the form of the spot on outer being given at Fig. 24, C 



Female. Grayish green above, often showing bluish in some lights. 

 The wing spots, although always present, (See Fig. 24, B ) is frequently very 

 small. Beneath, buffy yellow, tinged with grayish green on sides. The 

 spot on the outer tail feather is either very faint or replaced by a little 

 white on the inner web near the termination of the feather. 



There is frequently a superciliary stripe, and ring around the eye, of yel- 

 lowish. 



Fig. 24. 



C B A 



Black-tliroated Blue Warbler. A, head : B, outer taU feather, both of male ; C, spot at base of 

 wing of female. 



Adults in Autumn. Scarcely different from the spring dress. Young 

 males at this season have the head above overwashed with oliveaceous. Beneath 

 the black and yellow is faintly obscured with whitish. 



Nestlings. Male. Olive brown above ; sides of head very dark, with 

 lores black ; throat, lower eyelids, and line over eye, pale buff. x\bdomen, 

 bright sulphur yellow : white spot at base of primaries prominent. Female. 

 AVings and throat as in the same sex in autumn, but brownish above and more 

 buffy below. 



Dimensions. Length, 5.00; stretch, 7.96; wing, 2.24 ; tail, 2.02 ; 

 bill, .40 ; tarsus, .73. 



Comparisons. This is the only New England Warbler which is 

 blue, black and white : thus the male is distinguished. The female is quite 

 different, but may be recognized by the white patch on wing, but this is 

 not always readily seen, then she may be known by the peculiar, grayish 

 ^reen back, no other of our warblers being of just this color, and the fact that 

 there is no wing band. Young males always have tlie wing spot prominent 

 and this will serve for their identification. 



