BIRDS OF PENNSYLVANIA. 
265 
forest, but in groves, along the borders of streams, in orchards, parks 
and gardens he is common. Its nest is usually built at a considerable 
height in trees. 
Vireo flavifrons Vieill. 
Yellow-throated Vireo. 
Description (Plate 19). 
Length about ; extent about 9£ ; wing 3 ; tail 2| ; bill about .50 long and rather 
stout. Dusky spot in front of eye, a yellowish loral streak ; ring around eye, chin, 
throat and breast bright yellow; top of head, back and sides of neck, and upper 
part of back decided olive-green ; tertials edged with white; lower parts of back, 
rump, tail-coverts (above) and lesser wing-coverts ashy; belly to end of lower tail- 
coverts pure white ; sides a little grayish ; no spurious quill ; first and fourth quills 
equal in length. 
Habitat. —Eastern United States, south in winter to Costa Rica. 
This species is most common as a spring and fall migrant, arriving 
here late in April and departing in September. It breeds sparingly or 
irregularly in nearly all sections of the state, but is, apparently, much 
more frequently met with in the mountainous and elevated woodland 
regions, particularly in the northern counties, than elsewhere as a sum¬ 
mer resident. During migrations I have observed these bright yellow- 
throated songsters, which, although smaller, resemble somewhat the 
noisy Chat, in orchards, in trees along sidewalks and in lawns. Usually, 
however, this vireo is to be found high in trees of forests in the vicinity 
of streams. In the Eastern states this species is said to build in orchards, 
about buildings, as well as in woodland. In Pennsylvania the Yellow- 
throated Yireo always, I have found, breeds in woods, and commonly 
builds its lichen-covered abode twenty-five, thirty or forty feet above the 
ground. In the late summer, fall and winter months this bird feeds fre¬ 
quently on small berries. 
Vireo solitarius (Wils.). 
Blue-headed Vireo. 
Description. 
Length about inches ; extent 9 ; wing 2.90; tail 2£. Top of head, portion of neck 
behind, and sides of head leaden-gray ; rest of upper parts, including rump and tail- 
coverts, olive-green ; edges of some wing feathers and lateral tail feathers edged 
with greenish-white and whitish ; below white ; sides, flanks and crissum greenish- 
yellow and yellow, the latter paler on axillars and about crissum; spurious quill 
well developed, being about one-third as long as second; white ring around eye, 
white loral line, and a dusky spot below the latter. 
Habitat. —Eastern United States to the plains. In winter south to Mexico and 
Guatemala. 
The Blue-headed Yireo, like the species last described, is an inhabitant 
of woodland. It arrives here usually a few days before the Yellow- 
