YELLOW WAEBLER 211 



The Warbler is often victimized by the Cowbird. On 

 examining this nest, after the birds had left it, I found 

 that the rightful owners had evaded the responsibilities 

 of foster-parents to a slacker's young by building an 

 extra floor in the nest, snugly walling off the intruded 

 egg. Thanks to the wisdom of this pair of Yellow War- 

 blers, there is one less Cowbird. (Fig. 122.) 



What changes in the appearance of Yellow Warbler 

 babies, a few days brings ! At the end of a week, they are 

 partly feathered and have multiplied several times in 

 bodily weight. In two weeks, they are feathered and 

 some of the golden yellow tints are to be seen ; the colors 

 that aid us in distinguishing the species take their places 

 on breast and back. Much ado and excitement mark the 

 time for home-tie breaking. With vibrating wings and 

 encouraging words the devoted parents seem to say : 



''Do you see us? Don't be afraid, but please be 

 careful. ' ' 



One's bird affections are made stronger by sights 

 like these, and his enmity is increased toward all things 

 that destroy these innocent and beneficial friends of man. 



