BIRDS OF NOKTH AND MIDDLE AMERICA. 129 



with hrig-ht g-reen and 3'ellow, rarely with blue on head: usually plain 

 olive, olive-g-reen, or gra}' above (sometimes relieved by whitish or 

 3'ellowish wing-bars), and plain whitish or yellowish beneath. 



Nidijicatkm. —Nest (so far as known) suspended from a forked 

 branch, composed of line vegetable libers, mosses, lichens, etc.: eggs 

 white, usually more or less spotted. 



Range. — Temperate and tropical America, except Galapagos Archi- 

 pelago. 



The Vireos (sometimes called Greenlets) are acti\'e arboreal l)irds, 

 mainly insectivorous though feeding also on fruits and berries. As a 

 rule they are fair songsters, although some species are distinguished 

 for the oddity rather than melody of their notes. So far as known 

 they all ])uild pensile nests, and lay white eggs with a few dark specks. 



The family is peculiar to America, but chiefly tropical, and is repre- 

 sented b}' about seventy known species, referable to eight genera. 



KEV TO THE (iENERA OF VIREONID.E. 



a. Lateral toes relatively shorter, the inner toe (without claw) shorter than the 

 hallux (without claw), its claw not reaching beyond bas^e of middle claw. 

 h. Bill more slender, relatively less deep and compressed, its depth at frontal 

 antiaj not' greater than its width at same point; sides of maxilla without 

 grooves. 

 c. Tail slightly rounded, even, or emarginate; throat and chest not slate-gray. 

 d. Tenth primary rudimentary and concealed or else very small and narrow, 

 less than one-third as long as ninth; the latter longer than fourth; wing- 

 tip longer than commissure, or else the latter longer than tarsus. 

 e. Bill relatively longer and more slender, its depth at frontal anti;c not 

 greater (usually much less) than half the distance from nostril to tip 

 of maxilla, the latter measurement at least equal to length of gonys; if 

 the tenth primary obvious the ninth shorter than tifth: wing without 



whitish l)ars or other markings Vireosylva ( p. l;>0) 



ee. liill relatively shorter and stouter, its depth at frontal antiic e(iual to 

 much more than half the distance from nostril to tip of maxilla, the 

 latter measurement decidedly less than length of gonys; if tiie tenth 

 primary obvious the ninth longer than sixth; wing with two consi)icu- 



Dus white l)ars Lanivireo ( p. IGl ) 



(/(/. Tenth primary well developed, more than one-third (frequently one-half) 

 as long as ninth, the latter shorter than fourth (sometimes shorter than 

 first or, rarely, shorter even than secondaries); wing-tip shorter than 



commissure, the latter shorter than tarsus Vireo (p. 176) 



cr. Tail nuich rounded, throat and chest slate-gray Neochloe (p. "IW) 



I'll. Bill stouter, relatively deeper and more compressed, its depth at fnmtal antia' 

 decidedly greater than its width at same point; sides of maxilla with tine 



longitudinal grooves " Laletes ( p. 212) 



"'(. Lateral toes relatively longer, the inner toe (without claw) as long as or longer 



than hallux (without claw), its claw reaching decidedly beyond base of 



middle claw. 



I). Bill smaller and more slender, the culmen slightly decurveil terminally: smaller 



(wing less than 6"> mm. ) Pachysylvia i p. 214 ) 



''This feature may not be constant, only one specimen having l)een <'xainined. 

 10384— VOL 3—03 9 



