233 



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 nar- 

 rowed; 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; 



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