THE CHESTNUT-SIDED WARBLER. 231 



and woods, and seem to be as much on the ground as in 

 the trees. They depart for the South by the 10th or 

 15th of October. 



DENDROICA PENNSYLVANIA. Baird. 

 The Chestnut-sided Warbler. 



Motacilla Pennsylvanica, Linnaeus. Syst. Nat., I. (1766) 333. 

 Sylvia Pennsylvanica, Wilson. Am. Orn., I. (1808) 99. 



Sylvia icterocephala, Audubon. Orn. Biog., I. (1832) 306. Nutt. Man., I. 

 (1832) 380. 



DESCRIPTION. 



Male. Upper parts streaked with black and pale bluish-gray, which becomes 

 nearly white on the forepart of the back; the middle of the back glossed with 

 greenish-yellow; the crown is continuous yellow, bordered by a frontal and super- 

 ciliary band, and behind by a square spot of white ; loral region black, sending off 

 a line over the eye, and another below it; ear coverts and lower eyelid and entire 

 under parts pure-white, a purplish-chestnut stripe starting on each side in a line 

 with the black moustache, and extending back to the thighs ; wing and tail feathers 

 dark-brown, edged with bluish-gray, except the secondaries and tertials, which are 

 bordered with light yellowish-green ; the shoulders with two greenish-white bands ; 

 three outer tail feathers with white patches near the end of the inner webs. 



Female like the male, except that the upper parts are yellowish-green, streaked 

 with black ; the black moustache scarcely appreciable. 



Length, five inches; wing, two and fifty one-hundredths inches; tail, two and 

 twenty one-hundredths inches. 



This bird is a rather common summer inhabitant of all 

 New England, being most plentiful in Massachusetts and 

 the States south, and gradually growing more rare as we 

 advance north. It makes its appearance from the South 

 about the first to the middle of May, according to latitude, 

 and commences to build about the last week in this month 

 or the first in June. The nest is usually built in a small 

 fork of a low tree, often in bushes, but a few feet from the 

 ground. It is constructed of thin strips of pliable bark and 

 fine grasses : these materials are bent and intwined together, 

 and over the outside are pieces of caterpillar silk and cob- 

 webs, which are plastered on, seemingly to give the fabric 

 compactness and consistency. The nest is deeply hollowed, 

 and lined with horsehairs and slender strips of the bark of 



