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 fact they eat almost anything which they can glean in the insect line from the shrubbery and ground." Forbush (1929) says: "As the bird ranges from the ground to the tree-tops it takes most of the insects that any warbler will eat, among them flies, young grasshoppers and locusts, leaf-hoppers and many plant-lice, caterpillars both hairless and hairy, among them the gipsy, brown-tail and tent caterpillar, most of which are taken when young and small; also small wood-boring beetles are eaten, and other small insects of many species. The bird appears to be almost wholly insectivorous." _Behavior._--The eastern Nashville warbler is an active, sprightly, restless member of an active family, ranging in its foraging mainly in the lower story of the open woodlands and more often in the low trees and shrubbery around the borders of the forest. When thus engaged it is not particularly shy and often seems quite unconscious of the presence of an observer. On migrations it seems to be sociably inclined and may be seen associated with the mixed flocks of warblers that are drifting through the tree tops. At these seasons it often visits our orchards and the shrubbery in our gardens, giving us a glimpse of green and gold among the blossoms and opening leaves. J. W. Preston (1891) describes an interesting manner of foraging: "One will fly to the foot of a fir tree or other conifer and begin an upward search, hopping energetically from branch to branch until the very highest point is reached, when the bird drops lightly down to the foot of another tree, much as does the Brown Creeper. When an insect is discovered the bird secures it by a sudden bound, and, should the object be not easily dislodged, _Helminthophila_ sustains himself on flapping wings until his purpose is accomplished, which often requires several moments." _Voice._--Gerald Thayer gave Dr. Chapman (1907) a very good description of the songs and calls as follows: