SULID^E. CXXXI. 225 



c. Tarsus moderate, much longer than hind toe with claw. 

 d. Bill compressed; gular sac small. . . PHALACROCORACID^E, 133. 

 dd. Bill much flattened; gular sac very large. . PELECANID^E, 134. 

 cc. Tarsus extremely short, not longer than hind toe with claw; wings 

 and tail excessively long, the latter deeply forked. 



FREGATID^E, 135. 



FAMILY CXXXI. SULID^E. (THE GANNETS.) 



Bill long, cleft to beyond eyes, very stout at base, the tip not 

 hooked, the tomia irregularly serrate ; a nasal groove, but the nos- 

 tril abortive ; gular sac small, naked ; wings long, pointed ; tail 

 long and stiff, with pointed feathers ; feet stout. Body heavy, 

 similar to that of a goose, the tissues under the skin with air- 

 chambers as in the Pelicans. One genus with 5 or 6 species. 

 Gregarious sea-birds, found in most regions. 



344. SULA Brisson. (French, Sule.) 



a. Lower jaw, chin and throat densely feathered. (Dysporus.) 



678. S. bassana L. GANNET. White, black on wings ; yellow- 

 ish on head ; young dark brown, spotted. L. 36. W. 20. T. 10. 

 B. 6. N. Atl., S. to Florida, common N. (Eu.) (From Bass 

 Rock, Eng., where Gannets breed.) 



FAMILY CXXXII. ANHINGID^E- (THE DARTERS.) 



Bill very long, straight, slender, sharp, the tomia finely serrate ; 

 gular sac small, naked ; nostrils minute, becoming obsolete ; tail long, 

 stiff, fan-shaped, when spread, the feathers broad, the middle pair 

 in the adult transversely corrugated. Neck long, very slender, the 

 vertebrae (20 in number) of peculiar structure; feet short, far 

 back. A single genus, with 3 or 4 species ; swift, wary birds, their 

 movements in the water resembling those of a snake. 



345. ANHINGA Brisson. (Port., anhina ; Lat., anguina, snaky.) 



679. A. anhinga (L.). DARTER. SNAKE-BIRD. WATER TUR- 

 KEY. Chiefly black, with greenish lustre above ; neck with hair- 

 like plumes ; 9 largely buffy, back with pale streaks. L. 35. W. 

 14. T. 11. B. 3. Tropical Am., K to S. 111. 



FAMILY CXXXIII. PHALACROCORACID^E. (THE 



CORMORANTS.) 



Bill slender, about as long as head, nearly terete, but compressed, 

 strongly hooked, the cutting edges uneven ; gular pouch small. 

 Wings short ; tail very large, almost scansorial, of very stiff feath- 

 ers, often used as a support for the body ; legs set far back ; a 

 nasal groove with abortive nostrils. Colors in both sexes lustrous, 

 iridescent black ; in the breeding season usually with long, white, 



15 



