_Perissoglossa_, BAIRD, Rev. Am. Birds, 1864, 181. (Type, _Motacilla
tigrina_, GM.)
[Line drawing: _Perissoglossa tigrina_, Baird.]
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.
Perissoglossa tigrina, BAIRD.