WOOD WARBLERS 453 
ment of this trill is broken or divided into syllables, like zee, zee, zee, 
ze-ee-ee-eep. This latter variation is the one used by D. cerulea, and I 
could detect little or no difference in the songs of dozens of individuals. 
At best it is a modest little strain and far from deserving the encomium 
bestowed upon it by Audubon, who describes it as ‘extremely sweet and 
mellow;’ decidedly it is neither of these, and he must have confounded 
with it some other species. In addition to the song they utter the almost 
universal Dendroicine lisp and also the characteristic tchep of D. cor- 
onata, which I had previously supposed entirely peculiar to that bird.” 
659. Dendroica pensylvanica (Linn.). CHESTNUT-SIDED WAR- 
BLER. (Fig. 121.) Ad. #.—Crown bright yellow, a black line behind the 
eye; front part of the cheeks black; ear-coverts white; back streaked with 
black and margined with bright olive-green; wing-bars yellowish white; 
tail black, the outer feathers with white patches on their inner vanes at the 
tip; underparts white, the sides chestnut. Ad. ¢.—Similar, but somewhat 
duller in color. Ad. in fall and im.—Very different; upperparts bright yellow- 
ish olive-green, back sometimes streaked with black; wing-bars yellowish 
white; underparts pure, silky white, the sides in ads. with spots or patches of 
chestnut. L., 5°14; W., 2°45; T., 2°00; B. from N., °29. 
Range.—E. N. Am. Breeds mainly in the Transition zone from cen. 
Sask., nw. Man., cen. Ont., and N. F., s. to e. Nebr., Ills., Ind., n. Ohio, 
n. N. J., and R. I., and s. in the Alleghanies to Tenn., and S. C., and cas- 
ually in s. Mo. and the Wabash Valley; winters from Guatemala to Panama; 
in migration casual in Fla., the Bahamas, and s. Mex. 
Washington, abundant T. V., Apl. 19-May 30; Aug. 10-Oct. 14. Ossin- 
ing, tolerably common 8S. R., May 2-Sept. 24. Cambridge, abundant S. R.., 
May 5-Sept. 10. N. Ohio, T. V., May 2-25. Glen Ellyn, rare 8. R., com- 
mon T. V., May 1-Sept. 26. SE. Minn., common 8. R., May 3-Sept. 15. 
Nest, of strips of bark, leaf stems, etc., lined with tendrils and rootlets, in 
bushes, about 3 feet up. Eggs, 4-5, white, with numerous distinct and 
obscure cinnamon- and olive-brown markings, chiefly in a wreath about 
the larger end, ‘69 x ‘50. Date, New Haven, Conn., May 23; Cambridge, 
May 26; Ann Arbor, Mich., May 20; se. Minn., May 29. 
When settled for the summer, Chestnut-sided Warblers may be 
found in second growths, scrubby clearings, or the bushy borders of 
woodlands. There is a suggestion in their movements of the restless 
activity of the Redstart, as with drooped wings and slightly raised 
tail they flit among the lower growth. They have two songs, both of 
which closely resemble those of the Yellow Warbler, though a practiced 
ear can at once recognize the song of either. 
Adults of this species are too conspicuously marked to be mistaken 
for any other Warbler, but in the fall have a care in identifying the 
very differently colored young. 
660. Dendroica castanea (Wils.). Bay-BREASTED Wans.er. Ad. 2. 
—Forehead and cheeks black, a cream-buff patch on the sides of the neck; 
crown chestnut; throat, wpper breast, and sides chestnut-rufous; back brownish 
ashy, streaked with black; two white wing-bars, inner vanes of (ee tail- 
feathers with white patches at their tips; lower breast and belly buffy white. 
Ad. ¢.—Crown olive-green, streaked with black and with generally some 
chestnut; rest of upperparts as in the 7; underparts buffy white; breast and 
sides more or less stained with rufous. Ad. in fall and im.—Upperparts 
bright olive-green, indistinctly streaked with black; wings and tail much as 
