VIREOS 395 



7. Darker, wing bars narrower. California. 



huttoni. p. 399. 

 7'. Paler and grayer, wing bars broader. Texas and Arizona. 



stephensi, p. ;]99. 



6'. Wing bars tinged with yellow. Washington and Oregon, 



wintering in California obscurus, p. 899. 



Subgenus Vireosylva. 



Spurious primary if present decidedly shorter than tarsus ; wing without 

 light bauds. 



624. Vireo olivaceus (Linn.). Red-eyed Vireo. 



Adults. — Top of head gray, conspicuously bordered by white superciliary 

 and narrow black line ; blackish line through eye ; rest of 

 upper parts olive green ; wings without bands or spurious 

 primary ; under parts clear white. Young : similar, but back 

 brownish ash; sides washed with brown. Length: 5.50-6.50, 

 wing about 8.10-3.30, tail 2.15-2.80, exposed culmen, .50- 

 .55. 

 Distribution. — Breeds from the arctic regions south chiefly in the north- 

 eastern United States, but extending through Florida and to the Gulf of 

 Mexico ; west to Montana and Washington ; migrates to South America. 



Nest. — Hung ratlier low from a forked twig of a tree, made of strips 

 of birch and inner bark, dead leaves, and vegetable fibers, often patched 

 with bits of wasp nest and lined with pine needles, or stems and rootlets. 

 Eggs : 3 to 5, white, lightly specked with reddish brown, chiefly around 

 the larger end. 



Food. — Insects and small berries. 



The eastern red-eyed vireo is found occasionally in Colorado at the 

 base of the foothills, and has been recorded as far west as British 

 Columbia. 



625. Vireo flavoviridis (Coss.). Yellow-green Vireo. 



Like olivaceus, but sides and flanks bright olive green, axillars and 

 under tail coverts sulphur yellow. Length : 0.25-6.75, wing 2.v^0-3.20, tail 

 2.05-2.50. 



Distribution. — Valley of tlie Lower Rio Grande in Texas, south to South 

 America; accidental in Quebec and at Riverside. California. 



627. Vireo gilvus (VieilL). Warbling Vikeo. 



. {(/lilts. — Up])er jxirts olive gray, grayest on head and most olive on rump 

 and up])t'r tail coverts; irhite streak through eye: wings and 

 tail dusky brown, unmarked, wing with a well-developed spu- 

 rious primary ; sides of head pale brownish or huffy ; under 

 p;»rts white, shaded with olive yellow on sides. Young : top 

 Fig. 4'.«>. '>f h«'ad and hind neck pale grayish buff; rest of upjier parts 

 hutVy. wiu<;>! with huffy hai-s ; under parts jjure white, except 

 for Yellowish t.iil eoverts. Length: 5.»K)-5..")0, wing 2.(m-2.95, tail 2.10- 

 2.4(»," hill from nostril .80-. 82, depth at base .1.")-.1S. 



Distribution. — North America in general from Great Slave Lake to 

 northern Mexico ; breeds throughout the greater part of this range. In 

 winter to sotitheru Mexico. 



Xfst. — Similar to that of the red-eye, but smoother and more compact ; 

 hung in trees, usually at a considerable height, in open copses, along banks 



