62 BULLETIN 203, UNITED STATES NATIONAL MUSEUM 



the streak through the eye, and having less yellow on the crown. Dr. 

 D wight (1900) describes the first winter male as "above, bright olive- 

 green, lemon-yellow on the crown veiled by greenish tips. Below, 

 bright lemon-yellow, the crissum white or merely tinged with yellow. 

 Transocular streak black. Wing coverts plumbeous gray, edged with 

 olive-green, the greater and median tipped with white, yellow tinged, 

 forming two broad wing-bands." 



The birds are now practically adult in plumage. The first and sub- 

 sequent nuptial plumages are acquired by wear, which produces little 

 change beyond removal of the greenish tips. Subsequent winter 

 plumages are acquired by a complete postnuptial molt each July. 



The interesting hybrids between this and the golden-winged warbler 

 are discussed on pages 3 and 4. Kumlien and Hollister (1903) men- 

 tion a probable mating of this with the Nashville warbler. 



Food. — Nothing seems to have been published on the food of the 

 blue- winged warbler beyond that mentioned above as food given to the 

 young, which is doubtless eaten by the adults as well. It is apparently 

 wholly insectivorous, seeking its food near the ground in the weed 

 patches and underbrush where it lives and among the lower branches 

 of the trees in its haunts. Probably any small insects that it can find 

 in such places, as well as their larvae and eggs, including many small 

 caterpillars, are eaten. Small grasshoppers and spiders are probably 

 included. Prof. Aughey (1878) observed it catching small locusts 

 in Nebraska. It is evidently a harmless and a very useful bird in 

 destroying insects that are injurious to foliage. 



Behavior. — ^Dr. Chapman (1907) writes: "It is rather deliberate 

 in movements for a Warbler, and is less of a flutterer than the average 

 member of the genus Dendroica. Some of its motions suggest those 

 of the tree-inhabiting Vireos, while at times, as the bird hangs down- 

 ward from some cocoon it is investigating, one is reminded of a Chicka- 

 dee." And he quotes Burns as follows : 



Perched inconspicuously near the top and well out on the branchlets of a tree 

 or sapling, preferably facing an opening, if in a thicket ; it is in itself so minute 

 an object as to be passed unseen by many, more especially as it is much less 

 active than most of our Warblers. With body feathers puffed out to a delightful 

 plumpness, except for the backward sweep of the head while in the act of singing, 

 it remains motionless for quite a while. When it moves it is with a combination 

 of nervous haste and deliberation, and its song may be heard from quite another 

 part of the landscape with no apparent reason for the change. While it has its 

 favorite song perches, it is quite a wanderer and not infrequently sings beyond 

 possible hearing of its brooding mate, but of tener within fifty to two hundred feet 

 of the nest. 



Voice. — Aretas A. Saunders contributes the following study of the 

 songs of this warbler : "The territory song of the blue- winged warbler 

 consists of two long, buzz-like notes, the second usually lower in pitch 

 than the first and rougher in sound, hzzzzzzsr-'brrrrrrrr. The pitch in- 



