Perching Birds Chiefly Dull Colored. 
629. Blue-headed Vireo (Virco solitarius). L. 5.5; 
W. 2.9; B. .4. Ads. Lores and eye-ring white; crown 
and cheeks bluish slate-color; back olive-green; below 
white, sides washed with greenish yellow; two whitish 
wing-bars. Notes. Resembling in form those of Red- 
eyed or Yellow-throated Vireos but more varied, some- 
times acontinuous warble; a musical chatter, like that of 
the Yellow-throated and a trilled whistle. (Torrey. ) 
Range.—Eastern North Amerlea; breeds from Connecticut (and 
south along Alleghanies) north to New Brunswick and Manitoba; 
winters from Florida to Central America. 
629a. Cassin Vireo (V. s. cassint). Above wholly 
plumbeous-gray with scarcely, if any, olive tinge; 
below white, the sides gray faitly tinged with green- 
ish yellow; size of No. 629c. 
Range.—" Breeds from British Columbia and Idaho south along Pa- 
cific coast region end Nevada to Lower California; migrates to Arizo— 
na, New Mexico, and northern Mexico.’’ (Bailey.) 
629b. Plumbeous Vireo (V.s. plumbeus). Like 
No. 629, but back washed with the color of the head; 
white on breast and throat less pure. 
Range.—Rocky Moun:ain region; breeds from northern Mexico 
north to southwestern Dakota and Wyoming; winters south to south- 
ern Mexico, 
629c. Mountain Solitary Vireo (/. s. alticola). 
Larger than No. 629, W. 3.15, B. .46; head darker, its 
color extending over most of the back. 
Range.—Breeds in Alleghanies from North Carolina to Georgia; 
winters in Florida. P . 
629d. St. Lucas Solitary Vireo (V7. s. Jucasanus). 
Smaller than No. 629a, but bill longer and stouter, 
sides and flanks much yellower; young without 
brownish below, and resembling young of No. 629. 
Range.—Cape Region of Lower California. 
633. Bell Vireo (Vireo belli’). L.5. Above olive- 
green, crown grayer; lores and eye-ring white; two in- 
conspicuous whitish wing-bars; below white, sides 
tinged with yellowish. Most like, No. 627, but back 
greener, no white line back of eye. Notes. Resemble 
those of the White-eyed Vireo, but less harsh, song 
less emphatic. (Goss.) 
Range. Interior states from Illinois west to Plains; breeds from 
Texas to Minnesota; winters in Mexico. 
633.1. Least Vireo (Vireo pusillus). L. 4.8. Ads. 
Above gray, slightly tinged with greenish toward rump; 
below white, sides with little if any greenish tinge; 
one inconspicuous whitish wing-bar; lores and eye- 
ring inconspicuously grayish. 
Range.—Northwestern Mexico and northern Lower California; 
breeds north to Arizona and middle California. a 
634. Gray Vireo (Vireo vicintor). L. 5.5. Above 
slaty gray; below white tinged with grayish; one in- 
conspicuous wing-bar; lores and eye-ring gray; bill 
short. Notes. Song may be compared with the finest 
efforts of the Blue-headed Vireo with the added charm 
and mellowness of the song of the Yellow-throated 
Vireo. (Henshaw. ) 
Range.—Northern Mexico, north to western Texas, southeastern 
California, and southern Nevada; winters in Mexico. 
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