VIREO, 473 
olive-green and yellow; length 5.00-6.00, wing 
2.90-3.00 (2.94), tail 2.10-2.20 (2.19), bill from 
nostril .28-.30 (.29), tarsus .70-.73 (.71). West in 
woods, in undergrowth or lower branches of small 
trees. Hggs .79 x 57. Hab. Eastern North 
America, north to Fort Simpson and Hudson’s 
Bay, breeding chiefly north of United States; 
south, in winter, through eastern Mexico to 
Guatemala. 
629. V. solitarius (Wizs.). Blue-headed Vireo. 
g°. Back, etc, more grayish olive-green, less abruptly 
Gif at all) contrasted with the duller ash-gray 
of head and neck; gray of cheeks less abruptly 
contrasted with white of throat; sides and flanks 
less strongly tinged, with olive-green and yellow. 
(Young in first winter much browner than cor- 
responding stage of V. solitarius.) Length 5.00- 
5.60, wing 2.85-3.00 (2.90), tail 2.10-2.30 (2.16), 
bill from nostril .28-.31 (.30), tarsus .70-.78 (74). 
figgs .79 x 55. Hab. Western United States, 
east to Rocky Mountains, but chiefly (if not ex- 
clusively) Pacific coast in summer; in winter, 
south through western Mexico..... 629a. V. soli- 
tarius cassinii (Xantus). Cassin’s Vireo. 
f?. Larger (wing decidedly more than 3.00, tail not less than 
2.20). 
ae in plumage to V. solitarius, but upper parts 
much darker (“nearly uniform blackish plum- 
beous, with only a faint tinge of greenish on the 
back, which is essentially concolor with the 
crown”); wing 3.03-3.30, tail 2.21-2.31, bill from 
nostril .30-.36, tarsus .72-.75. Hab. Higher 
southern Alleghanies (western North Carolina, 
CLC.) creseeeeee 629c. V. solitarius alticola Brewsr. 
Mountain Solitary Vireo.! 
é. Sides and flanks tinged with plumbeous-gray, but with little 
if any olivaceous or yellowish tinge; back, rump, and 
upper tail-coverts plumbeous-gray, very slightly, if at all, 
tinged with olive-green. 
Above plumbeous, or plumbeous-gray, with the usual 
white markings on wings and sides of head; lower 
parts white, the sides and flanks strongly tinged with 
plumbeous-gray; length 5.75-6.15, wing 3.05-3.30 
1 Vireo solitarius alticola Brewst., Auk, iii. Jan. 1866, 111, 
60 
