° ■ 1916 J Fry, Seasonal Decline in Bird Song. 35 



last record for one is the fifteenth. The single note whistles did 

 not diminish till the seventeenth, and from that date they gradu- 

 ally decreased, but were heard occasionally throughout the re- 

 mainder of the period. 



Data on the Cowbird {Molothrus ater aier) are very scant for 

 they were few in number. Their Starling-like calls were heard at 

 intervals up to about July 17. Whether or not any diminution 

 had begun before the first covild not be determined, but probably 

 not. After the seventeenth they were rarely heard and the last 

 record is on the twenty-third. 



The first song of the Goldfinch (Astragalinus tristis trisUs) 

 was not noted till the seventeenth of July, though in all probability 

 it could have been heard occasionally prior to that. By the 

 twenty-third it was singing quite frecpently though at no time 

 did it become common, and this condition continued throughout 

 the remainder of the period. Since the decline set in some time 

 after August 10, there are no data concerning the matter. The 

 flight calls were heard occasionally from the beginning, and when 

 the period of song began, they increased in frequency. 



The Yellow-throated Vireo (Lanivireo flavifrons) remained in 

 full song till about the nineteenth, when the diminution began 

 which continued to the middle of the first week of August. The 

 song did not cease altogether, however, and throughout the rest 

 of the period it was heard almost every day, though infrequently. 



The decline of the House Wren's song (Troglodytes aedon aedon) 

 is about the same as that of the Yellow-throated Vireo. The dimi- 

 nution began about the nineteenth and continued till the thirtieth. 

 The low ebb of song reached then about held its own through the 

 rest of the period, and it was heard only once or twice each day 

 after the last week of July. 



The W'ood Pewee (Myiochanes virens) began its decline almost 

 imperceptibly around July 20, and from that day it gradually 

 became less and less, though the daily diminution was scarcely 

 evident. August 10, when the studies came to an end, it could 

 still be heard quite frequently in sunny spots in the woods. 



The story of the Red-eyed Vireo (Vireosylva olivacea) is almost 

 identical with that of the Pewee, though perhaps its diminution 

 is a trifle more marked. It too, gradually began to lessen in volume 



