_Oporornis_, BAIRD, Birds N. Am. 1858, 246. (Type, _Sylvia agilis_,
WILS.)
[Line drawing: _Oporornis formosus._
517]
GEN. CHAR. Bill sylvicoline, rather compressed; distinctly notched at
tip; rictal bristles very much reduced. Wings elongated, pointed, much
longer than the tail; the first quill nearly or quite the longest.
Tail very slightly rounded; tail-feathers acuminate, pointed; the
under coverts reaching to within less than half an inch of their tip.
Tarsi elongated, longer than the head; claws large, the hinder one as
long as its digit, and longer than the lateral toes. Above
olive-green; beneath yellow; tail and wings immaculate. Legs yellow.
This group of American Warblers is very distinct from any other. The
typical species is quite similar in color to _Geothlypis
philadelphia_, but is at once to be distinguished by much longer
wings, more even tail, and larger toes and claws. It is also very
similar to _Seiurus_, differing chiefly in the longer wings, larger
claws, and absence of spots beneath.
Throat and crown ash-color; a white ring round the eye. No
black on the side of the head … _O. agilis._
Throat and superciliary stripe yellow; top of the head and a
streak beneath the eye black … _O. formosus._
Oporornis agilis, BAIRD.