414 NORTH AMERICAN BIRDS. 



Above light ash. Upper tail-coverts and forehead much paler th»n the 

 back, the former vs^ithout waved lines. Axillars whitish. 



Inner webs of secondaries paler towards edges, but not of well- 

 defined white. Concealed bases of tail-feathers, except sixth, white. 

 Tarsus shorter than the gape of mouth. Length, 10.00 ; extent, 

 14.50 ; wing, 4.70 ; tail, 4.70 ; bill above, .85 ; tarsus, .93 . . horealis. 

 B. Black cheek-stripes not involving upper border of eye or ujjper eyelid, 

 which is whitish, and not meeting across the forehead, its upper edge be- 

 hind the eye with scarcely a lighter border. No jDatch of white on lower • 

 eyelid. Under parts unvaried white ; in female obscui'ely waved. Base of 

 under mandible whitish. Length about 9 inches. 



Above light ash. Upper tail-coverts and forehead decidedly paler than 

 the back. Axillars whitish. 



Inner webs of all secondaries (except innermost) white to shaft, 

 except for less than terminal half, which is black along the shaft. 

 Concealed base of tail white, except on sixth feather. Tarsus equal 

 to the gape .......... excubitor. 



C Black cheek-stripes involving upper eyelid, as in A, but without patch 

 of white below the eye ; meeting in a narrow, sometimes inconspicuous, line 

 across the forehead, its upper edge behind the eye not bordered by lighter. 

 Beneath plain white, or very obscurely waved in ludovicianus (the female ?). 

 Bill, when mature, entirely black. Length about 8.50 inches. 



Above dark plumbeous-ash. Upper tail-coverts and forehead scarcely 

 paler than the back. Sides and breast tinged with bluish-gray. 



Black of loral space rather hoary along upper border. Frontal 

 dark line inappreciable or wanting. Inner webs of secondaries 

 paler only along tlie marginal half, and not abruptly white. Axil- 

 lars plumbeous. Tail-feathers, except the innermost, with a con- 

 cealed well-defined white patch at base, .largest on the more ex- 

 terior one. Bill from nostril, .50. Under parts often with very 

 obscure faint waved lines (in the female?). White patch on wing 

 reaching aljout to middle of Oi'st primary. Tarsus equal to the 

 gape. Length, 8.50; wing, 3.72; tail, 4.10; bill al)ove, .82 ; tar- 

 sus, 1.00 .......... ludovicianus. 



Black of loral space without any lightening above it. Frontal 

 black band well marked. Inner webs of secondaries (except in- 

 nermost) pure white to shaft, except along rather more than ter- 

 minal half, where the shaft is bordered by black. Axillars whitish. 

 Tail-feathers black to base, except the loose fibres, which are gray- 

 ish. Bill from nostril, .GO. Under parts without waved lines. 

 White patch on wing reaching nearly opposite to end of first 

 primary. Tarsus about equal to the gape. Length. 8.75 ; wing, 

 4.20; tail, 4.40; bill above, 1.00; tarsus, 1.20 .... elegans. 



Above light asli-color. LTpper tail-coverts and forehead much lighter 

 than the back, the former sometimes almost white. Sides and breast 

 generally nearly pure white. 



Black of loral space with conspicuous hoary margin above it. 

 Inner web of secondaries much as in C. ludovicianus. Axillars 

 whitish. Tail-feathers with concealed white patch at bases of all 

 the feathers. Bill from nostril about .50. No waved lines beneath. 

 White patch on wing reaching nearly opposite to end of first pri- 

 mary. Tarsus longer than the gape. Length, 8.50 ; wing, 4.05 ; 

 tail, 4.25; bill above, .83 ; tarsus, 1.12 .... excubitoroides. 



