NATATORES. PUFFINUS. 527 
coverts, and secondary quills fine bluish-grey. Quill 
feathers blackish-grey. Legs yellow, tinged with grey. 
Tail rounded. 
Fig. 2. The bird before having acquired maturity. 
Head, neck, rump, tail, and under plumage ash-grey. A 
spot of blackish-grey at the anterior angle of the eye. 
Upper plumage deep ash-grey, with a slight tinge of 
brown. Bill and legs yellow, tinged with grey. 
Genus PUFFINUS, Ray. SHEARWATER. 
GENERIC CHARACTERS. 
Bitt as long as, or longer than, the head, straight, slender, 
subeylindrical, with the tip of the upper mandible arched 
and hooked, that of the lower one bent downwards, and fit- 
ting into the upper without any angle at the symphasis. 
Nostrils basal, tubular, with two distinct truncated openings 
in front. 
Wings long, acuminate, with the first quill-feather the 
longest. ‘Tail rounded. Legs having the tarsi of mean 
length, laterally compressed. Feet of three toes, entirely 
webbed ; hind toe represented by a straight nail or claw. 
General contour rather long. 
The Shearwaters are distinguished from the birds of the 
preceding genus by the comparative slenderness and weak- 
ness of the bill, and the peculiar modification of its tip, both 
mandibles being bent downwards. As also in the nostrils, 
which are formed (as it were) of two tubes cemented sideways 
together, and opening outwardly by two separate truncated 
apertures instead of one, as in the Fulmar. Their legs are 
placed farther backwards, and the tarsi are longer in propor- 
tion and very much compressed, a formation which, without 
Young. 
