NATATORES. MERGULUS. 429 



on the wing, spotted with brownish-black. Bill black. 

 Legs and toes red. 



In winter, the old birds have the cheeks, throat, and all 

 the under plumage, pure white. The crown of the head 

 and the dorsal plumage black. 



GENUS MERGULUS, RAY $ VIEILL. ROTCHE. 



GENERIC CHARACTERS. 



BILL shorter than the head, thick, broader than high 

 at the base; culmen arched; upper mandible indistinctly 

 grooved; under one with the symphasis very short and 

 oblique ; tips of both mandibles notched. Commissure arched. 



Nostrils lateral, round, situated at the base of the bill, and 

 partly covered by the small feathers of the antise. 



Wings and tail short. 



Legs abdominal, short ; feet of three toes, all directed for- 

 wards, and united by a membrane. 



tn consequence of the distinct character exhibited in the 

 form of the bill of the only known species of this genus 

 (intermediate between the genera Guillemot and Auk, and 

 with both of which it has been at different times classed, ac- 

 cording to the views taken of its prevailing affinities by dif- 

 ferent systematists), it has latterly been established by VIEIL- 

 LOT as a type, and he has given to the genus the title of 

 Mergulus, the name it before had from our countryman 

 RAY, and which has also been adopted by Dr FLEMING, Mr 

 STEPHENS, and others. It is a bird of the ocean, and a na- 

 tive of the Arctic Regions ; and its habits in many respects 

 resemble those of the Guillemots, Auks, and Starikis. 



