Cardenilla pusilla
Order Passeriformes
Family Parulidae
♂ Male.– Upper parts bright olive-green in a strong light; crown black; forehead and under parts bright yellow.
♀ Female.– Black crown generally wanting.
Nest, on the ground in wet woods.
Eggs, white, speckled with reddish-brown, and with lavender.
The Wilson’s Warbler is a rather uncommon migrant through New England and New York, occurring in the latter half of May and in September. It breeds rarely in the extreme northern and eastern portions of Maine. Generally found in trees or bushes near water, along the edges of swamps or in the bushy borders of streams, though, like most migrants, it may appear, when Warbler more than usually common, in any suitable cover. Its song suggests to most observers the song of the Yellow Warbler; it is briefer, less lively, and ends in some rapidly delivered notes. It is a restless little bird, difficult to observe. The yellow of the under parts first attracts attention; then a glimpse of its dark back distinguishes it from the female Yellow Warbler, but a sight of the black crown bordered by the yellow forehead is necessary for an absolute identification.
Hoffmann – A Guide to the Birds of New England and Eastern New York (1904)