BIRDS OF NEW YORK 



167 



Yellow-billed Tropic-bird. Phaethon americanus Grant. 



5 nat. size 



New York specimen (immature) in State Museum. 



describes its capture in Our Birds and tlicir Haunts, page 615 [see also Coues, 

 N. O. C. Bui. 5 :63 ; compare also, Maynard's Birds of Eastern North America, 

 p. 474]. 



Family SULIDAE 



Gannets 



Bill long, very stout at base, tapering and slightl}' decurved toward 

 the tip, somewhat serrate and very deeply clef t ; nostrils abortive ; gular pouch 

 naked but small; wings long and pointed; tail long and wedge-shaped of 12 

 to 18 feathers; legs short and stout, placed nearl)- at the center of bod>-; 

 head large; neck rather long; plumage compact; two carotids; ambicns 

 femorocaudal and semitendinosiis muscles present but the accessories 

 absent ; stenium long and narrow ; coracoids directed forward ; a remarkable 

 development of the pneumatic cells extending beneath the skin and among 

 the muscles. 



