174 BULLETIN 179, UNITED STATES NATIONAL MUSEUM 



I can find no evidence that this phoebe differs in any respect in 

 its habits from its more northern relative. It evidently breeds in the 

 area indicated above, for A, W. Anthony told Major Bendire (1895) 

 that he found nests of this phoebe in that region in abandoned min- 

 ing shafts and prospect holes, as much as 25 feet below the surface of 

 the ground. How much farther south, east, or north it breeds does 

 not seem to be known. No form of Say's phoebe has been found 

 breeding in the Cape region of Lower California, where the species 

 seems to be only a winter visitor and rather rare at that. 



The subspecific status of the birds of this species that have been 

 taken in winter in the Cape San Lucas region evidently has not been 

 determined. 



Dr. Louis B. Bishop (1900a) described a northern race of this 

 species, which he named Sayornis saya yukonensis^ based on the 

 study of 15 specimens collected in the Yukon Valley, Alaska. He 

 characterized it as "similar to Sayoimis saya but darker, the gray 

 of the upper parts clearer — less scorched, with the pale edgings of 

 the wing-coverts and secondaries narrower; the tail longer; the bill 

 shorter and relatively broader." Mr. Eidgway (1907) relegated it 

 to synonymy ; and the A. O. U. Check-list has not yet admitted it. 



The measurements of eight eggs average 20.4 by 15.5 millimeters ; 

 the eggs showing the four extremes measure 22,1 by 16.3 and 19.0 by 

 15.3 millimeters. 



EMPIDONAX FLAVIVENTRIS (Baird and Baird) 



YELLOW-BELLIED FLYCATCHER 



Plates 21, 22 



HABITS 



To most of us this pretty little flycatcher is known only as a spring 

 and fall migrant. It is not often seen then, as it is a shy, retiring 

 bird, frequenting the low, wet, swampy thickets along streams or the 

 borders of swamps or ponds. Since it is mostly silent on migra- 

 tions, its characteristic notes do not tell us of its presence, and as 

 it generally succeeds in keeping out of sight it must be sought for 

 diligently. In its summer home its voice betrays it, but there, also, 

 the searcher must invade the moist, gloomy morass of some northern 

 forest bog, beneath the shade of spruces and firs, and endure the 

 attacks of hoards of black flies and mosquitoes, to get even a glimpse 

 of this woodland waif. 



Dr. Samuel S. Dickey, who has had considerable experience with 

 this flycatcher, says in his notes: "In the Northern States and in 

 Canada they are met with in the shadowy underwoods of evergreens. 



