FAMILY VIKEOJSID^. VIKEOS. 



271 



FAMILY VIREONID/G. 



Vireos. 



Upper mandible, with very smalt hook at tip ; first primary, very short 

 in some species, in others nearly as long as second; toes, joined at base. 

 Plain colored birds, usually greenish or grayish, but often showing a faint 

 wash of yellow on underparts; tail, always without white spots. 



Group 1. Wing, less than 2.37 inches long. 



f'rowQ, grayish; orbital ring and lores, dull white. Rarely occurs east of 

 Illinois. 



Bell's Vireo. 



Vireo hellii. 

 See No. 480. 



Crovvu, grayish, often tinged with olive; orbital ring and lores, 

 yellow. 



White=eyed Vireo. 



Vireo noveborarensis, and races. 

 See No. 478. 



