JTor Ceact)er£ anti J^tutients 



How to Name the Birds 



STUDIES OF THE FAMILIES OF PASSERES 



BY FRANK M. CHAPMAN 



FIFTH PAPER 



Family ii. Vireos. Vireonida. 



Range. — An exclusively American family containing some fifty species, 

 which are distributed from Hudson Bay to Argentina. Twelve of the 

 number, all members of the genus Vireo, reach the United States, and 

 eight of these are found east of the Mississippi. 



Season. — North of the sub-tropics Vireos are migratory birds, the 

 White-eyed and Blue-headed Vireos alone, of our eastern species, win- 

 tering as far north as Florida. In the Middle States they are first rep- 

 resented by the Blue -headed Vireo, which comes in the latter half of 

 April. The remaining species appear in May, and the Red -eyed and 

 Blue-headed Vireos are with us until the middle of October. 



Color. — Olive-green, without streaks or spots, is so characteristic a 

 color among Vireos that they were formerly often spoken of as " Green - 

 lets." This color is confined to the upper surface, the under parts in 

 most species being white or whitish, with often a yellow tinge, or some- 

 times strong, clear yellow. 



External Structure. — Our Vireos are small birds averaging somewhat 

 less than six inches in length, with the bill rather slender, but cylin- 

 drical, not tapering to a point, and distinctly hooked. The outer primary 

 is usually very small or 'spurious,' and in some cases is apparently absent. 

 The base of the bill is beset with bristles, a fact which, in connection 

 with its hooked tip, might lead to the confusion of Vireos and Fly- 

 catchers, but in the latter family the bill is wider than deep at the base, 

 and in the former as deep as or deeper than wide. 



Appearance and Habits. — With the exception of the White-eyed and 

 Bell's Vireos, which are thicket-haunters, our Vireos are tree-inhabitants, 

 lawn, garden, orchard and woodland rarely being without some member 

 of this group at the proper season. While, like the Flycatchers and 

 Warblers, the Vireos are insect-eaters, they differ from the members of 

 both these groups in their manner of securing food. They are not 

 wing-feeders like the Flycatchers, nor nervous, active flutterers like the 

 Warblers. Comparatively deliberate in actions, they hop from limb to 

 limb, carefully examining the bark and leaves in search of prey as they 

 progress. 



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