284 
BIRDS OF PENNSYLVANIA. 
way, * writing of this species, very aptly says, “it is one of the most 
agile of its tribe, its quick and restless movements being more like 
those of thevRedstart than those of its nearest kindred.” Food consists 
largely of various small winged insects; plant-lice, ants and spiders are 
also fed upon to a considerable extent. 
Dendroica cserulea (Wils.). 
Cerulean Warbler. 
Description. 
Length 4\ to 5; extent about 8g inches. 
Male, in spring. —Above bright blue, streaked with black; the crown somewhat 
brighter and darkest; below white; the breast and sides with blue or bluish-black 
streaks ; two white wing bars ; tail-feathers, except central pair, with white patches 
on inner webs, near the end. 
“ Female. —Greenish-blue above, brightest on the crown ; beneath white, tinged 
with greenish-yellow, obsoletely streaked on the sides; eyelids and a superciliary 
line greenish-white.” {Hist. N. Am. B.) 
Habitat .—Eastern United States and southern Canada to the plains. Rare or 
casual east of central New York and the Alleghanies. Cuba (rare) and Central 
America in winter. 
The Cerulean or Blue Warbler I have found in eastern Pennsylvania 
only as a very rare spring and fall migrant. During the last ten years 
1 have seen but five of these birds, one was observed in an apple orchard 
in May, the others were all seen in the tops of tall forest trees. In the 
western counties of the state this species is reported to be tolerably 
frequent during migrations, and Dr. Yan Fleet says it breeds in Clinton 
county; and in Somerset county Dr. H. D. Moore has noted it as a rare 
summer visitor. The viscera of two individuals which I have examined 
contained spiders and small beetles, etc.; the stomach of one bird was 
destitute of all food except portions of a wasp-like insect. 
/ 5 
Dendroica pensylvanicaf (Linn.). 
Chestnut-sided Warbler. 
Description {Plate 73, Fig. 3, Male). 
Length about 5 ; extent about 7| inches. 
Male, in spring .—Above greenish-olive and pale bluish-gray (the latter especially 
on back of neck) streaked with black ; top of head yellow, with black border (in 
some specimens feathers of forehead and those above the black lores and eyes are 
whitish) ; broad triangular patch below eye from base of mandible black, and from 
this a narrow black line joins the showy chestnut stripe which extends back along 
sides to flanks ; ear-coverts and portion of sides of neck, and rest of under parts pure 
white, two yellowish wing-bands; three outer pairs of tail-feathers white on inner 
webs towards end. 
* Ornithology of Illinois. — Ridgw. 
tThe bill in this species, and also in D. castanca. is broader, and the bristles are longer than in others 
of the genus. 
