BLACK-THROATED GREEN WARBLER. 
279 
extends over the eye ; the rose colour also reaches to the 
base of the bill, where it is speckled with black and white. 
The female is of a light yellowish flaxen colour, streaked with 
dark olive, and whitish ; the breast is streaked with olive, 
pale flaxen, and white ; the lining of the wings is pale yellow ; 
the bill, more dusky than in the male, and the white on the 
wing less. 
BLACK-THROATED GREEN WARBLER SYLVIA 
VIRENS — Plats XVII. Fig. 3. 
Motacilla virens, Gmel. Syst. i. p. 985 Le Figuier & cravate noii’e, Buff. v. p. 
298. — Black-throated Green Flycatcher, Edw. t. 300. — Green Warbler, Arct. 
Zool. ii. No. 297 Lath. Syn. iv. p. 484, 108 Turton, Syst. p. 607. — 
Parus viridis gutture nigro, The Green Black-throated Flycatcher, Bartram , p. 292. 
S YL VICO LA VIRENS. — Swainson. 
Sylvia virens, Bonap. Synop. p. 80. 
This is one of those transient visitors that pass through 
Pennsylvania, in the latter part of April and beginning of 
May, on their way to the north to breed. It generally fre- 
quents the high branches and tops of trees, in the woods, in 
search of the larva of insects that prey on the opening buds. 
It has a few singular chirruping notes ; and is very lively and 
active. About the 10th of May it disappears. It is rarely 
observed on its return in the fall, which may probably be 
owing to the scarcity of its proper food at that season obliging 
it to pass with greater haste ; or to the foliage, which prevents 
it and other passengers from being so easily observed. Some 
few of these birds, however, remain all summer in Pennsyl- 
vania, having myself shot three this season, (1809,) in the 
month of June ; but I have never yet seen their nest. 
This species is four inches and three quarters long, and 
seven broad ; the whole back, crown, and hind head, is of a 
rich yellowish green ; front, cheeks, sides of the breast, and 
line over the eye, yellow ; chin and throat, black ; sides, 
