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FAMILY XLIV.— ALCIN^. AUKS.
Bill not longer than the head, much compressed, generally very high, in the species approaching the next family rather slender. Nostrils small, linear, basal, and sub-marginal. Head large, broadly ovate, anteriorly narrowed; neck short and thick; body full, compact, ovate, or somewhat elongated. Feet short, rather stout, placed far behind; tibia bare for a short space; tarsus very short, compressed, anteriorly scutellate; toes three, of moderate length, scutellate, webbed. Claws strong, arched, acute. Plumage dense, blended, soft. Wings small, narrow, pointed. Tail very short.
Tongue slender, trigonal; oesophagus very wide, within the thorax extremely dilated; stomach rather large, muscular, with the epithelium dense and longi- tudinally rugous; intestine long and wide; cceca of moderate size. Trachea simple, with a single pair of inferior laryngeal muscles. Egg generally single.
Genus I.— MORMON, Illiger. PUFFIN.
Bill about the length of the head, nearly as high as long, exceedingly compressed, at the base as high as the head, obliquely furrowed on the sides; upper mandible with a horny dotted rim along the basal margin; its dorsal line decurved from the base, the ridge narrow, at the base rounded, the sides rapidly sloped, with three or four curved oblique grooves, the edges sharp, their outline nearly straight, the tip deflected, very narrow, but obtuse; lower mandible with the angle very narrow, and so placed that the base of the bill is inflected beyond the perpendicular, the dorsal line a little convex at first, towards the end ascending, and nearly straight, the sides perpen- dicular, the edges sharp; the tip very narrow, obliquely truncate; gap-line extending downwards a little beyond the base of the bill, and furnished with a soft corrugated extensile membrane. Nostrils marginal, linear, direct, in the horny part of the bill. Head large, roundish-ovate; neck short and thick; body full and rounded. Feet short, rather stout, placed far behind;
