BIRDS OF PENNSYLVANIA. 153 



said that these notes in the latter part of the summer are almost the 

 only ones heard in the woods. The thin-bottomed, thick-walled and 

 somewhat saucer-shaped nest, built usually on a thick, horizontal tree 

 limb, is composed, internally, of grass stems, fine fibres of roots or 

 other soft substances, and covered externally with lichens, which are 

 held in place by cobwebs or " glued to the other materials by the bird's 

 saliva." The eggs, four or five in number, are yellowish -white, with 

 reddish -brown and lilac spots, generally in a ring about the larger end. 

 They measure about .75 of inch in length, and a little over .50 of an 

 inch in width. I have never found Wood Pewees feeding on small 

 fruits, but have always observed that they feed exclusively on insects. 

 Audubon, however, states during the winter months he has observed 

 these birds in Florida, Louisiana and other of the Southern States, 

 feeding on " different berries, as well as insects." 



GENUS EMPIDONAX. OABANIS. 

 463. Empidonax flaviventris. BAIRD. 



Yellow-bellied Flycatcher. 



DESCRIPTION. 



Above olive-green (very similar to the back of Vireo noveboracensis) ; crown 

 rather darker ; a broad yellow ring around the eye ; the sides of the head, breast and 

 body, and a band across the breast like the back, but lighter ; the rest of the lower 

 parts bright sulphur yellow ; no white or ashy anywhere on the body ; quills dark 

 brown ; two bands on the wing formed by tips of the primary and secondary 

 coverts, the outer edge of the first primary and of the secondaries and tertials pale 

 yellow, or greenish yellow. Tail feathers brown, with the exterior edges like the 

 back ; upper mandible dark brown ; lower mandible yellow ; legs and feet black ; 

 iris brown. In the autumn the colors are purer, the yellow is deeper, and the mark- 

 ings on the wings of an ochry tint. 



Dimensions of a female : Length, 5| inches ; extent, 8 ; wing, 2| inches. 



Hab. Eastern North America to the plains, and from southern Labrador south 

 through eastern Mexico to Panama, breeding from the northern States northward. 



The Yellow-bellied Flycatcher, according to my observation, is 

 found in eastern Pennsylvania as a rather rare spring and autumnal 

 visitant. It arrives, in this locality, from its southern winter resorts 

 about the last of April, and after remaining a few days, frequenting 

 chiefly wooded districts, passes northward to breed. This Flycatcher, 

 about the 20th of September, as:ain makes its appearance in our 



