XXXVI. SYNOPSIS. 



C. arcticus, Linn. -v. 2, p. 381-383 



C. septentrionalis, Linn. - \. 2, p. 385-387 



Gen. gi. URIA. Bill moderate, strong, straight, point- 

 ed, compressed; upper mandible slightly curved towards the 

 point: nostrils basal, lateral, linear, pervious, placed longi- 

 tudinally, and partly closed by a membrane covered with 

 feathers: legs placed far backwards, tarsi short; three toes 

 in front, none behind: wings short; first quill longest: tail 

 short. 



U. Troile, Lath. -v. 2, p. 390-392 



U. Grylle, Lath. - \. 2, p. 394 



Gen. 92. MERGULUS. Bill shorter than the head, 

 thick, convex, conical, slightly curved, covered at the base 

 with feathers; both mandibles notched at the tip: nostrils 

 basal, lateral, round, partly concealed by a plumose mem- 

 brane: wings rather short; first and second quills longest: 

 tail short. 



M. Alle, Selbj. v. 2, p. 396 



Gen. 93.' MORMON. Bill shorter than the head, higher 

 than long, much compressed anteriorly; both mandibles 

 arched, transversely furrowed, and notched at the tip; cul- 

 men more elevated than the crown of the head: nostrils 

 basal, marginal, linear, almost entirely closed by a large 

 naked membrane: legs short, placed far backwards; three 

 toes in front, no hind toe; claws curved: wings short; first 

 and second quills longest: tail short. 



M. Fratercula, Temm. - v. 2, p. 398 



Gen. g4> ALCA. Bill straight, large, compressed, much 

 curved towards the point; both mandibles with four trans- 

 verse grooves, and covered with feathers at the basal portion: 

 nostrils lateral, marginal, linear, placed near the middle of 

 the bill, almost entirely closed by a membrane covered with 

 feathers: legs short, abdominal; three toes in front, no hind 

 toe; claws slightly curved : wings short: tail pointed. 



A. Torda, Linn. - v. 2, p. 402-404 



A. impennis, Linn v. 2, p. 405 



