IS84-] BiCKNELL OH the Singing of Birds. ^37 



Thryothorus ludovicianus. Carolina Wren. 



This species is of too irregular occurrence to afford the requi- 

 site data for a knowledge of its habits of song during the entire 

 3'ear. I have, however, heard its full song in April, May (June 

 24?) and August. 



Troglodytes aedon. House Wren. 



From its arrival late in April until after midsummer the full 

 song of the House Wren is to be heard, and, though sometimes 

 ending with July, it is often continued through the tirst week of 

 August. August 15 is my latest date for the true nuptial song. 

 Usual!}" before this time, when singing continues so late, the song 

 begins to change, and, becoming increasingly weaker and less 

 defined, may be extended beyond the middle of the month. With 

 the change of song a change of habits begins, and likewise 

 gradually progresses. The birds forsake the vicinity of dwell- 

 ings and their accessory buildings, of which for more than three 

 months they have been familiar and self-assertive occupants. To 

 the lay observer they have disajDpeared, but the experienced eve 

 will detect them inhabiting the rocks and shrubbery of wild and 

 unfrequented localities, often remote from human habitation. In 

 such places the autumn song is to be heard, though to one famil- 

 iar only with the characteristic song of the earlier season its 

 authorship would hardly be susj^ected. It has none of the spon- 

 taneity and vigor of the spring song, but is a low, rambling wai"- 

 ble. I have listened certainly a full minute wdiile it continued 

 without interruption. An approach to this song may sometimes 

 be heard when the species is becoming silent in August, as I 

 have already stated ; while in September a decided reversion 

 towards the spring song is sometimes noticeable. 



Although the bird regularly sings in the autumn, at this season 

 its subdued song and retiring disposition render it easily over- 

 looked ; so'that absence of records of song in the autumn at a 

 time when observation in other years has showm the bird to sing, 

 cannot be taken as a guarantee of silence, as it could be in the 

 case of a more conspicuous species. The precise limits of the 

 autumn song-period I have not yet been able clearly to define, 

 but It may be said in general terms that singing begins early in 

 September, continuing through this month and sometimes into 



