BLUE YELLOW-BACK WARBLER. 79 



hangs like a Titmouse, and searches the cups of even the smallest flowers 

 for its favourite insects. 



I am inclined to think that it raises two broods in a season, having 

 seen and shot the young on the trees, in Louisiana, early in May, and 

 again in the beginning of July. The nest is small, formed of lichens, 

 beautifully arranged on the outside, and lined with the cottony sub- 

 stances found on the edges of different mosses. It is placed in the 

 fork of a small twig, and so far towards the extremity of the branches 

 as to have forced me to cut them ten or fifteen feet from it, to pro- 

 cure one. On drawing in the branch carefully to secure the nest, the 

 male and female always flew toward me, exhibiting all the rage and ani- 

 mosity befitting the occasion. The eggs are pure white, with a few red- 

 dish dots at the larger end, and were in two instances four in number. 

 It was several years before I discovered one of these nests, so small are 

 they, and so difficult to be seen from the ground. 



This species is found throughout the United States, and may be con- 

 sidered as one of the most beautiful of the birds of those countries. It 

 has no song, but merely a soft, greatly prolonged twitter, repeated at 

 short intervals. It returns southward, out of the Union, in the beginning 

 of October. 



Sylvia americana, Lath. Ind. Ornith. vol. ii. p. 520. — Ch. Bonaparte, Synops. of 



Birds of the United States, p. 33. 

 Yellow-backed Wahbler, Lath. Synops. vol. iv. p. 440. 

 Blue Yellow-back "Warbler, Sylvia pusilla, Wils. Americ. Ornith. vol. iv. 



p. 17. PI. 28. fig. 3. Male. 



Adult Male. Plate XV. Fig. 1. 



Bill longish, depressed at the base, nearly straight, tapering to a 

 point. Nostrils basal, oval, half concealed by the feathers. Feet of or- 

 dinary length, slender ; tarsus compressed, covered anteriorly with a few 

 long scutella, acute behind, longer than the middle toe ; toes scutellate 

 above, free ; claws arched, slender, compressed, acute. 



Plumage blended, glossy. Wings longish, little curved, the first quill 

 longest. Tail slightly forked, of ordinary length, the twelve feathers ra- 

 ther narrow and obtuse. A few longish bristles at the base of the upper 

 mandible. 



