484 THE BIRDS OF MAINE 



d'. Pale yellowish white on under parts. Black-poll 



Warbler, (immature), 

 d". Pale cream buff below, especially on flanks. Bay- 

 breasted Warbler, (immature). 

 ??. No white bars on wing, 

 a^ Tail with white spots, blotches, or patches. 

 b\ Wings, rump and tail bluish gray. Prothonotary Warbler, 

 b*. Wings, rump and tail not bluish gray, 

 c'. Under parts decided yellow, no white patch at base of 



primaries. Hooded Warbler, (female and immature), 

 c**. Under parts pale yellowish, a white spot at base of 

 primaries. Black-throated Blue Warbler, (female). 

 a?. Tail without white spots, blotches or patches, 

 b'. Crown different color from back, 

 c'. Crown or forehead black. 

 d'. Crown black, forehead yellow. Wilson's Warbler, (adult), 

 d". Crown not black, forehead black. Northern Yellow- 

 throat, (male). 

 c". Crown or forehead neither of them black, 

 d'. Crown ashy with concealed chestnut patch in center, 



eye ring white. Nashville Warbler, 

 d'^. Crown feathers orange at base ; eye ring yellow. 

 Orange-crowned Warbler. (Hypothetical List). 

 b". Crown same color as back, 

 c' Belly white or whitish and distinctly contrasted with the 

 yellow throat and breast, 

 d'. Black spot before the eye. Yellow-breasted Chat, 

 d^. No black spot before the eye. 

 e'. Outer tail feathers shortest. Northern Yellow-throat, 



(female), 

 e". Outer tail feathers same length as others; white eye 

 ring. Nashville Warbler, (immature). 

 c*. Belly yellow or yellowish. 



d'. White spot on wing at base of primaries. Black- 

 throated Blue Warbler, (female), 

 d''. No white spot on wing at base of primaries, 

 e'. Inner web of tail feathers yellow. Yellow Warbler, 



(female). 

 e''. Inner web of tail feathers not yellow, 

 f. Forehead yellowish. Wilson's Warbler, (immature), 

 f*. Forehead not yellowish, 

 g'. Under tail coverts white, Tennessee Warbler, (imma- 



t\u-e). 

 g''. Under tail coverts not white, 

 h'. No eye ring; outer tail feathers shortest. Northern 

 Yellow-throat, (female). 



