BUFF-BREASTED FLYCATCHER 257 



the branch with spider webs; tliey are smoothly lined with the finest 

 grasses, phmt down, horsehair, and more or fewer feathers. All five 

 of the nests are more or less profusely decorated with what look like 

 pale gray lichens or spider cocoons, but these are probably broken 

 bits of the small leaves of a low-growing weed referred to by Mr. 

 Willard. They are all about the same size, 2^^ to 3 inches in outside 

 diameter, li/o to 1% in inside diameter, ll^ to V^ deep inside, and 

 about 2 inches in outside height. 



Eggs. — The buff-breasted flycatcher lays ordinarily either three or 

 four eggs. Mr. Lusk (1901) says that, of the sets of which he has 

 records, 50 percent were sets of three, 30 percent sets of four, and 20 

 percent sets of two eggs each. All five sets in the Thayer collection 

 contain four eggs each ; and Mr. Willard found one set of five eggs. 

 What few eggs I have seen are ovate, without gloss, and plain creamy 

 white and uimiarked. The measurements of 30 eggs average 15.5 by 

 11.9 millimeters; the eggs showing the four extremes measure 16.0 

 by 12.4, 15.C by 12.7, 14.7 by 11.5, and 15.6 by 11.3 millimeters. 



Plumages. — Young birds in juvenal plumage are much like the 

 spring and summer adults, but they are browner above, and the 

 median and greater wing coverts are broadly tipped with dull buff 

 or "cinnamon-buff," instead of grayish or buffy white. 



Fall and winter adults are more richly colored than spring and 

 summer birds, the upper parts more buffy, instead of "hair brown," 

 the wing bands more suffused with light buff, the chest often tawny- 

 buff, and the throat and belly pale yellow and buff, but there is 

 much individual variation. Mr. Swarth (1904) says: "The darkest 

 colored one I have, a female, has the breast deep ochraceous buff, 

 w^ith the throat and abdomen but little paler; while a rather large 

 sized male in fresh unworn plumage, has the upper breast yellowish 

 buff, fading to pale yellowish on the throat and abdomen, almost 

 white along the median line." 



I have seen no specimens in actual molt, but adults in June, July, 

 and August are in more or less badly worn plumage. Probably, as 

 with certain other Empidonaces, the post juvenal and postnuptial 

 molts take place after the birds have retired to their wdnter homes. 

 There is probably a prenuptial molt of at least some of the body 

 plumage in the spring, for Mr. Swarth (1904) states that "specimens 

 taken in April frequently have a few new feathers scattered over the 

 back." 



Food. — The only published account of the food of the buff-breasted 

 flycatcher that I can find is the following recent report by Cottam 

 and Knappen (1939), which I quote in full: 



From the limited data available, it apparently like others of Its kin feeds on 

 Those insects that are most available. The contents of the single stomach 



