Birds of America
By John James Audubon, F. R. SS. L. & E.
GENUS IV.--PUFFINUS, Briss. SHEARWATER.
Bill of the length of the head, rather slender, nearly as deep as broad at
the base, much compressed toward the end, nearly straight, being slightly
recurved, with the tips decurved; upper mandible with a cere at the base,
extending narrow to the nostrils, which are dorsal, each covered with a lateral
convex plate, and opening anteriorly, with an elliptical aperture, dorsal line
as far as the nostrils nearly straight; then suddenly deflected, afterwards
slightly concave, towards the end decurved, the ridge very broad and convex at
the base, narrower beyond the nostrils, from which a groove runs obliquely on
each side, sides convex, nearly erect, edges sharp, tip or unguis strong,
decurved, much compressed, very acute; lower mandible with the angle very long
and narrow, the dorsal line beyond it decurved, the sides sloping outwards, the
edges sharp and inflected, the unguis decurved, acute. Head rather large,
oblong; neck rather short; body moderate. Feet rather large; tibia bare for a
short space below; tarsus of moderate length, compressed, reticulated with
angular-scales; hind toe obsolete, but with a small conical deflected claw; fore
toes long, slender, connected by webs; outer toe slightly longer than third.
Claws arched, compressed, acute. Plumage full, close, elastic, rather compact
above. Wings very long, narrow, the first quill longest. Tail of moderate
length, graduated, of twelve rounded feathers.