PEOCELLARIIDTE, PETRELS. GEN. 298-300. 327 



the wings extremely long; the feet large. The elegant little "Mother Carc}''s 

 chickens" or "stormy petrels" (genus Thalassidroma oi authors; gen. 303-8, 

 beyond) are a fourth group, marked bj' their small size, slight build, aud 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 ^ if^^HB^^SW ^s*^ 

 vessels at sea, often following their course for manj' ^ .^ ("r ^' >^ 



miles, to pick up the refuse of the cook's galley. 

 Some of them, like gen. 307, have remarkably long ^^ =s^--^E-^-- ""^ 



legs, with fused scutella, flat obtuse claws, and the ^ — ==— 



. ,, T , . , . ,, , „ rio. 209. stormy Pelrel (Leacli'd). 



hallux exceedingl}^ 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 lamime, like a 

 duck's ; the colors are bluish and white. 



298-300. Genus FULMAHtTS Leach. 



*Tail 16-feathered ; bill longer than the tarsus. (Ossifraga.) 

 jtf / 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 ; "comnion off Monterey " 

 {Cooper). NuTT., ii, 329 ; Aud., vii, 202 ; Laave. in Bd., 825. giganteus. 



** Tail 12-14-feathered ; bill not longer than the tarsus. {Fulmarns and Priocella.) 

 ^"^2- Fulmar. Bill obviously shorter than the tarsus. Adult white, the mantle 

 pale pearly blue, frequently extending on the neck aud tail ; quills blackish- 

 browu ; usually a dark spot before the eye ; bill yellow, feet the same tinged 

 with greenish. Young : smok}'' gray, paler below, the feathers of the back 

 and wings dark-edged ; colors of bill and feet obscured. Length usually 

 about IGJ, but fi-om 15 to 18 ; wing 11-13 ; tail 4-5 ; tarsus about 2 ; bill 

 l|--lf , about f deep and almost as wide at base ; nasal tubes f . Extraor- 

 dinarily abundant in the North Atlantic; S. to IT. S. in winter. Nutt., ii. 

 331 ; Aud., vii, 204, pi. 455; Lawr. in Bd., 825 glacialis. 



"^ Var. PACiFicus will probably average considerably darker on tlie mantle, with a 

 weaker bill. N. Pacific Coast. Aud., vii, 208 ; Lawk, in Bd., 826 ; Coues, Proc. 



1 Phila. Acad. 1866, 28. 



fy~ Var. EODGERSii. 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 ; Coues, ibid. 1866, 29 ; Bd., Trans. 

 Chicago Acad, i, 323, pi. 34, f. 1. 



^'^^ '> Slender-billed Fidmar. 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 gull ; usually a small 

 dark spot before the eye ; feet yellow ; bill j'ellow, oljscured on the tube, at 



