Perissoglossa tigrina, Baird.
962
Gen. Char. Form of Dendroica, but bill slender, acute, with very obsolete notch; the commissure gently arched or curved from the base; the gonys also straight, or even slightly concave. Tongue lengthened, narrow, deeply bifid (for one third), and deeply lacerated or fringed externally at the end; the edge along the median portion folded over on the upper surface, but not adherent.
The curvature of the bill in Perissoglossa tigrina is quite peculiar among the Sylvicolidæ with notched bills. Some Helminthophagas (without notch) approximate this character, though in none, excepting H. bachmani, is it in equal amount,—all the others having the gonys very slightly convex, instead of straight, or even slightly concave.
It is most probable that the Helinaia carbonata of Audubon belongs here, as it appears very closely allied to the type of this genus. The two species may be distinguished as follows:—
Common Characters. Male. Top of head black. Above olive, becoming yellowish on rump. Head, neck, and lower parts bright yellow, becoming whitish posteriorly. Dorsal feathers with black centres; breast and sides streaked with black. A black streak through the eye.
P. tigrina. Large white patches on inner webs of tail-feathers.
Sides of head and middle of throat tinged with chestnut. One large white patch on wing, covering both rows of coverts. Outer web of lateral tail-feather blackish.
P. carbonata. No white patches on tail-feathers.
No chestnut about head. Two bands on the wing, the anterior one white, the posterior yellow. Outer web of lateral tail-feather whitish.