ee ha Dwicut, The Philadelphia Vireo. 263 
been so timed that I have really studied the birds from the middle 
of June to the first of September. The male Vireos are in full 
voice during June, but toward the end of the month the song 
period rapidly wanes, and after the first days of July their notes 
are not very often heard save as a subdued warble at rare intervals. 
Now the birds ramble about in the bushes almost exclusively, 
instead of resorting, as has been their wont, to favorite perches 
high in the trees. Early in July, in the second week, the young 
begin to leave the nests (which, I regret to say, I have not been 
fortunate enough to find) and betray their presence like all incon- 
siderate fledglings by importunate demands for food; and no 
sooner are they able to shift a little for themselves than the 
parents have still further trouble thrust upon them in the shape of 
the autumn moult. This begins as early as the 2oth of July and 
seems to be pretty well completed during the second week of 
August. By this time the young have also acquired their fall 
plumage, which is not appreciably different from that of the adult. 
Young and old are now found associating with small restless 
bands of would-be migrants, perhaps a couple of Magnolia or 
Black-throated Green Warblers, a Red-eyed Vireo, a stray Red- 
start, in fact almost any of the summer sojourners, not forgetting 
a Chickadee or two ever ready with their irrepressible remarks. 
After the middle of August, the Philadelphia Vireos seem to dis- 
appear for good —at least I have not found them later than this 
—and the summer cycle of their life is completed. 
The birds are far less abundant than the Red-eyed Vireos over 
the same area, which outnumber them perhaps ten to one, and 
frequently the whole day passes without my seeing or hearing a 
single bird. Each summer I am able to locate upwards of a 
dozen pairs, but unless the males are singing they may give no 
token of their presence. The device of squeaking on the back of 
the hand sometimes has charms for them while at others, par- 
ticularly when they are moulting, it has no effect whatever. 
Usually the device does not fail to stir up the nearest White- 
throated Sparrows, who storm with untiring vigor until all the 
other birds in the vicinity have come to see what the row is about. 
The Olive-backed Thrushes, the Magnolia Warblers, the Canadian 
Warblers, the Redstarts, the Red-eyed Vireos, yes, all the birds 
