PROCELLARIIDH, PETRELS.— GEN. 298-300. 327 
the wings extremely long; the feet large. The elegant little “‘ Mother Carey’s 
chickens” or ‘‘stormy petrels” (genus Thalassidroma of authors; gen. 303-8, 
beyond) are a fourth group, marked by their small size, slight build, and other 
characters ; their flight is peculiarly airy and flick- 
ering, more like that of a butterfly than of ordinary 
birds ; they are almost always seen on wing, appear 
to swim little if any, and some, if not all, breed in 
holes in the ground, apparently like bank-swallows. 
Like other petrels they gather in troops about 
vessels at sea, often following their course for many ‘ 
miles, to pick up the refuse of the cook’s galley. 
Some of them, like gen. 307, have remarkably long 
legs, with fused scutella, flat obtuse claws, and the 
hallux exceedingly minute ; in the rest, the feet are 
of an ordinary character. The exotic genus Prion typifies a fifth group, of five 
or six species; here the bill is expanded, and furnished with strong laminz, like a 
duck’s; the colors are bluish and white. 
Fic. 209. Stormy Petrel (Leach’s). 
298-300. Genus FULMARUS Leach. 
* Tail 16-feathered ; bill longer than the tarsus. (Ossifraga.) 
Giant Fulmar. The largest of the petrels, equalling most of the alba- 
trosses in size; length 3 feet; extent 7; wing 20 inches; tail 8; bill 4, the 
nasal case nearly 2. Plumage dark dingy gray, paler below, often whitening 
in places; bill and feet yellow. Pacific Coast; “common off Monterey” 
(Cooper). Nutr., ii, 329; Aun., vii, 202; Lawr. in Bp., 825. GIGANTEUs. 
** Tail 12=14-feathered ; bill not longer than the tarsus. (/ulmarus and Priocella.) 
Fulmar. Bill obviously shorter than the tarsus. Adult white, the mantle 
pale pearly blue, frequently extending on the neck and tail; quills blackish- 
brown; usually a dark spot before the eye; bill yellow, feet the same tinged 
with greenish. Young: smoky gray, paler below, the feathers of the back 
and wings dark-edged; colors of bill and feet obscured. Length usually 
about 164, but from 15 to 18; wing 11-13; tail 4-5; tarsus about 2; bill 
14-13, about ? deep and almost as wide at base; nasal tubes 3. Extraor- 
dinarily abundant in the North Atlantic; S. to U.S. in winter. Nurrv., ii. 
331; Aup., vil, 204, pl. 455; Lawr. in Bp., 825. . . - . GLACIALIS. 
Var. pactricus will probably average considerably darker on the mantle, with a 
weaker bill. N. Pacific Coast. Avp., vii, 208; Lawr. in Bp., 826; Cousrs, Proc. 
Phila. Acad. 1866, 28. 
Var. nopGErsi. The mantle dark, as in pacificus, but much restricted, most of 
the wing coverts and inner quills being white ; primaries mostly white on the inner 
webs, their shafts yellow. A particular condition of the last variety? N. Pacific 
Coast. Cass., Proc. Phila. Acad. 1862, 290; Couns, ibid. 1866, 29; Bp., Trans. 
Chicago Acad. i, 323, pl. 34, f. 1. 
Slender-billed Fulmar. Bill little if any shorter than the tarsus. Adult 
white, with pearly blue mantle; primaries pearly whitish basally, white- 
tipped, crossed with definite black, much as in a herring cull; usually a small 
dark spot before the eye; feet yellow; bill yellow, obscured on the tube, at 
