This handsome bird is wholly unlike any others of the Vireos, having a bright yellow throat and breast; the upper parts are greenish and the wings and tail gray, the latter with two white bars. They are fairly common breeding birds in northern United States, placing their handsome basket-like structures in forks of branches and at any elevation from the ground; the nests are like those of the preceding Vireos but are frequently adorned on the outside with lichens, thereby adding materially to their natural beauty. The four or five eggs are pinkish or creamy white, speckled about the large end with reddish brown. Size .80 × .60. 629. BLUE-HEADED VIREO. _Lanivireo solitarius solitarius._ Range.--Eastern United States, breeding from southern New England and the northern states north to Hudson Bay; winters in the Gulf States and southward. A beautiful Vireo with a slaty blue crown and nape, greenish back, white wing bars and underparts, the flanks being washed with greenish yellow; a conspicuous mark is the white eye ring and loral spot. They build firm, pensile, basket-like nests of strips of birch and grapevine bark, lined with fine grasses and hair, suspended from forks, usually at low elevation and often in pine or fir trees (of some twenty nests that I have found in New England all have been in low branches of conifers). Their three or four white eggs are specked with reddish brown. Size .80 × .60. 629a. CASSIN'S VIREO. _Lanivireo solitarius cassini._ Range.--United States west of the Rockies; north to British Columbia. Similar to the last but with the back grayish. 629b. PLUMBEOUS VIREO. _Lanivireo solitarius plumbeus._ Range.--Rocky Mountain region, breeding from Mexico to Dakota and Wyoming. Like the Blue-headed Vireo but with the yellowish wholly replaced by leaden gray. [Illustration: Yellow-throated Vireo.] [Illustration 384: Creamy white.] [Illustration: White.] [Illustration: Blue-headed Vireo.] [Illustration: left hand margin.] Page 383 629c. MOUNTAIN VIREO. _Lanivireo solitarius alticola._ Range.--Mountains of Carolina and Georgia; winters in Florida. Said to be larger and darker than _solitarius_ proper. From all accounts, the habits, nests or eggs of this species differ in no wise from many of those of the northern Solitary Vireo, whose nests show great variations in size and material. 629d. SAN LUCAS VIREO. _Lanivireo solitarius lucasanus._ Range.--Southern Lower California. Similar to cassini but with the flanks more yellow. Their nesting habits or eggs will not differ from the others. 630. BLACK-CAPPED VIREO. _Vireo atricapillus._ Range.--Central Texas north to Kansas; winters in Mexico.