Birds of America
By John James Audubon, F. R. SS. L. & E.
GENUS I.--SEIURUS, Swains. WOOD-WAGTAILS.
Bill rather short, straight, slightly broader than deep at the base,
compressed toward the end, the edges a little inflected, the dorsal lines of
both mandibles slightly convex, the notches very slight, the tip acute.
Nostrils basal elliptical. General form slender; head ovato-oblong. Feet of
ordinary length; tarsus slender, compressed, covered anteriorly with a long
undivided piece and three inferior scutella; toes of moderate length, slender;
the first a little stouter than the third, the inner slightly shorter than the
outer, which is adherent at the base; claws of moderate length, very slender,
much compressed, moderately arched, acute. Plumage soft, blended. Bristles
very small. Wings of moderate length; the first or outer quill little shorter
than the third, which is longest. Tail of moderate length, even.