370 
Synopsis of the Birds 
by a narrow membrane ; webs full, entire ; bind toe merely 
a sharp nail: nails long, compressed, curved, acute. Wings 
long, slender, rather acute ; first primary longest. Tail 
moderate, rounded, of twelve feathers. 
Female similar to the male. Young but little different 
from the adult. Moult twice a year without changing their 
colors. Colors more or less grayish. Species of middling 
size. 
Chiefly nocturnal : chasing at twilight, or in stormy days, 
and hiding from the sun in clefts of rocks, or in the bur- 
rows of small quadrupeds, which they dislodge. Much 
more aquatic than any bird of their family ; combine the 
powers of flying and diving. Keep on the wing for several 
days, and dive even for their food, escaping from danger by 
either means. Constantly at sea, residing among breakers, 
hardly ever seen on shore. Feed almost exclusively on fishes. 
Breed socially : dig with their sharp nails deep holes in the 
ground, where they lay but one egg. Young born with long 
down. Furnish the wretched inhabitants of the Frozen 
Zone with food and clothing. 
Spread all over the world. A natural genus, eminently 
distinguished by its power of diving, much less allied than it 
appears to Procellaria. Forms the link between the Longi- 
pennes, and the diving web-footed birds. 
311 . Puffinus cinereus, Cuv. Bill more than two inches 
long, depressed at base, compressed where the point swells ; 
tail cuneiform ; tarsus two inches long. 
Adult light cinereous, wings and tail blackish-ash ; be- 
neath white ; bill and feet yellowish. 
Young slate-color, beneath varied with cinereous ; bill 
blackish. 
Cinereous Petrel , Lath. LePuffinjBuff.pl. enl . 962 . young. 
Shear-water Petrel oj Wilson's list ? Procellaria pvffinus and 
cinerea, L. 
