BiCKNKLL 0)1 the SingiiiiT oj Birds. 215 



Siurus motacilla. Large-hillhi) Water-Tiiuush. 



My notes on this species, although incomplete, seem to indicate 

 two song-periods ; the first ending in June or early in July ; the 

 later confined to a brief period of late July or early August. I 

 do not regularly hear its song after June has well advanced, but as 

 the birds are not common near me, I have not had opportunity 

 for full observation. Before the end of July the birds seem to 

 feel the migrating impulse and begin to grow restless. They ma\' 

 then be found in places which have not known them through the 

 breeding season, and songs, often of full continuance and power, 

 ma}' again be heard. My record gives July 33 and August 4 as 



limiting dates for the brief second song-period. 



« 



Geothlypis trichas. Maryland Yellow-throat. 



There is probabl}^ a dual season of song with this species, 

 which is obscured by variation in the singing-time with individ- 

 uals. Though it usually remains in song all through the sum- 

 mer, in the last weeks of July and the first of August singing is 

 less general and less spirited than either before or after. Often 

 after the middle of August songs will be louder and more fre- 

 quent than for weeks previously. Singing may cease at anv time 

 from about the middle of August to the end of the month, or first 

 part of September (August 13 and 19, to September 3, 4, 11 and 

 13) ; but September singing is unusual. The moult takes place 

 in August, and is completed in September, when the birds 

 become fat. 



With this species the habit of song-flight is well developed. 

 The little black-masked bird seems to believe it necessary 

 that singing should continue through the whole course of the 

 flight, and as the ordinary song, with which it begins, comes 

 to an end while yet the bird is in the air, the time is filled 

 out bv a disarranged medley of notes verv different from its 

 usual utterance. I have not often seen these performances before 

 mid-summer, and the August songs of the species are most fre- 

 quently those which accompany these flights, which are oftenest 

 indulged in the late afternoon or towards evening. This species, 

 and the Oven-bird, and Yellow-breasted Chat appear to be the 



