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The Singing of Birds. E. P.Bieknell. 
Vireo gilvus. Warbling Vireo. 
In favorable seasons this Vireo sings through May, June, July, 
and the first half of August. But, whether it be because of un- 
favorable conditions or from scarcity of birds, in some years its 
song is so interrupted in July that during most of the month 
singing is the exception rather than the rule. 
Singing may cease at any time during the first two weeks of 
August : later in the month the species is not often heard from, 
although I have a few dates of song in the third and fourth weeks. 
The true second song-period seems not to begin before the last 
days of the month, or September, when for a week or more the 
species may be generally in song. Latest dates for singing are 
September 14 and 18. 
Auk, I, July, 1884. p. 
