532 ORNITHOLOGY AND OOLOGY. 



SUB^ORDER GAVI^. 



Family SULIDiE. The Gannets. 



Bill rather long, straight, sides compressed, very strong, tapering to the point, 

 which is a little decurved; nostrils hardly observable; wings very long; tail long 

 and cuneate; toes long, and all joined by full webs; gular sac moderate. 



SULA, Bp.issdN. 



Sula, Brisson, Ornith. (1760). (Type Pelecanus bai>sa7iu!;.) 



Bill rather longer than the head, straight, stout at the base, with the sides com- 

 pressed, grooved near the tip, which is a little curved, the cutting edges serrated 

 irregularly; nostrils basal and scarcely perceptible; wings lengthened; tail rather 

 long and much graduated; tarsi short and stout; toes long, and joined together by 

 full webs; claws moderate, the middle one serrated; gular sac ratlicr moderate. 



These birds usually frequent almost inaccessible rocky islands, where they con- 

 gregate in great numbers during the season of reproduction, at other times migrat- 

 ing along the coast. Their flight is rapid, powerful, and long-continued. 



SULA BASSANA. — Brisson. 



The Common Gannet ; Solan Goose. 



Pelecanus bassamis, Linnreus. Syst. Nat. (1766), 217. 



Sula bassana, Nuttall. Man., IL (1834) 495. Aud. Orn. Biog., IV. (18-38) 222. 

 lb., Birds Am., VII. (1844) 44. 



Description. 



General color of the plumage white; bill bluish-gray; bare space around the eye 

 anfl on the throat blackish-blue; primaries bro^vnish-black, first longest. 



Adult. — The color of the plumage generally is white, the head and hind neck 

 being of a fine buff-yellow; alula and primaries brownish-black; shafts white for 

 about two-thirds their length ft'om the base, thence gradually becoming dark-brown , 

 bill pale bluish-grav, greenish at the base, the lines on the upper mandible blackish- 

 blue: bare space in the region of the eye, and down the centre of the throat 

 blackish-blue; iris white; tarsi, toes, and their webs, blackish-brown; the lines of 

 scutelhu on the tarsi and toes green; claws bluish-white. The female resembles the 

 male, but is rather smaller. The young have the head, neck, and upper plumage 

 dark -brown, each feather terminating with a triangular white spot; under plumage 

 grayish-white, the feathers broadly margined with grayish-brown. 



