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 § Vizrtzt. ROTCHE. 
GENERIC CHARACTERS. 
Brut 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 antiz. 
Wings and tail short. 
Legs abdominal, short ; feet of three toes, all directed for- 
wards, and united by a membrane. 
In 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 Vie1t- 
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 FLemine, 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. 
