26 PETRELS. 



varying size on under side of wing, white. North Atlantic, 

 south to the Newfoundland Banks and west coast of Africa. 

 Rare in summer. 

 f. Forked-tailed Sooty Petrels. Oceanodroma. 



Small Petrels ; bill, about two-thirds as long as head, 

 nasal tubes, about half its length, Fig. 22. 



fig 22 ; tips of toes of outstreached 

 feet not reaching tip of tail, fig. 23 ; 

 tarsus, shorter than toes ; wings, 

 folding beyond the deeply forked 

 tail; the bill and feet are wholly X>, B, f, 1. 



black. 



1. LEACH'S PETREL, O. LEUCORHOA. 8,00; sooty- 

 black, lighter beneath, and with a decidedly palish brown 

 space on middle of wing ; spot on Fig. 23. 



rump, white. North Atlantic and 

 north Pacific Oceans ; breeds on our 

 coast from Me. northward in June, 

 nesting usually in burrows, dug by 

 the birds in the surface of peaty 

 soil on islands, but occasionally on 

 the face of earthy or sandy cliffs, 

 like Bank Swallows. Common from 

 June until Oct. 



g. Long-legged Petrels. 

 Oceanites. 



Small; bill, weak, not half as 33, B, f, 1. 1-5. 

 long as head, fig. 24 ; tips of outstreached toes reaching be- 

 yond tail, fig. 25 ; tarsus, much longer than toes ; wings, 

 Fig. 24. long, folding beyond the nearly 



square tail. 



1. WILSON'S PETREL, O. 

 OCEANICUS. 7.00; sooty-black 

 throughout, a little lighter be- 

 ll), B, g, 1. neath; wings and tail, wholly 

 black ; webs of toes, mostly yellow. North and South At- 



