EASTERN NASHVILLE WARBLER 109 



Young. — The period of incubation is said to be from 11 to 12 days, 

 and probably the female does most of it, though Mr. Ejiight (1908) 

 says: "One bird relieves the other on the nest and at times when 

 the eggs are very near the hatching point I have seen the male bring 

 insects to its mate on the nest. Possibly he may feed the female at 

 earlier stages of incubation but I have not seen him do so. Both 

 birds feed the young, giving them at first soft grubs and caterpillars, 

 later on small beetles, flies and similar insects. * * * The young 

 leave about the eleventh day after hatching." 



For a further study of the nesting behavior of the Nashville war- 

 bler, the reader is referred, to an excellent paper on the subject by 

 Louise de Kiriline Lawrence (1948). 



Plumages. — Dr. D wight (1900) calls the natal down "sepia-brovsm," 

 and describes the juvenal plumage of the Nashville warbler as follows : 



"Pileum hair-brown, back darker, olive tinged, and rump olive- 

 green. Below, pale yellowish wood-brown, straw-yellow on abdomen 

 and crissum. Wings and tail olive-brown broadly edged with bright 

 olive-green, the median and greater coverts tipped with pale buflf- 

 yellow forming two wing bands. Lores and auriculars mouse-gray, 

 the orbital ring pale buff." 



The sexes are alike in juvenal plumage. A postjuvenal molt occurs 

 in July and August that involves the contour plumage and the wing 

 coverts but not the rest of the wings or the tail. This produces a 

 first winter plumage in which young birds become practically indis- 

 tinguishable from adults in many cases, but the chestnut crown patch 

 is generally smaller and more veiled in the younger male and is often 

 lacking in the young female. 



Dr. D wight (1900) says that the first nuptial plumage is "acquired 

 by a partial prenuptial moult which involves chiefly the crown, sides 

 of head and throat, but not the rest of the body plumage nor the wings 

 and tail. The head becomes plumbeous gray, the edgings only half 

 concealing the rich chestnut of the crown. The orbital ring is white 

 and conspicuous. Wear is marked, bringing the gray of the nape into 

 contrast with the greenish back, later exposing the chestnut of the 

 crown." 



A complete postnuptial molt in July and August produces the fully 

 adult plumage. In fresh fall plumage the head is browner than in 

 spring, the back is grayer, the crown patch is more veiled with gray 

 tips, and the breast is tinged with brownish. The females are paler 

 than the males, with less chestnut in the crown. Adults probably 

 have a partial prenuptial molt similar to that of young birds. 



Food. — ^Very little has been published on the food of the Nashville 

 warbler. Knight (1908) says that "the food of the adults consists of 

 beetles, larvae of various insects and the eggs of various insects. In 



