222 AVES: TUBINAKES. — XXXIII. 



664. S. paradisaea Briinnieh. Arctic Tbkn. Bill carmine 

 throughout; plumage as in hirundo, but darker below. L. 14 to 

 17. W. 10 to 11. T. 7 to 8. B. 1^. Smaller than hirundo, but 

 tail proportionally much longer. Arctic, S. to N. Y. (_Eu.) 



eee. Outer tail-feather with both webs white. 



665. S. dougalli Montagu. Roseate Tern. Bill black, usu- 

 ally orange at base below ; mantle very pale ; rosy-tinted below in 

 breeding season. L, 14 to 17. W. % T. 5 to 8. B. 1^. Atlan- 

 tic coast. (Eu.) (To Dr. McDougaU, of Scotland.) 



aa. Wing less than 7; tail deeply forked, about half wing. {Stemula Boie.) 



666. S. antillarum Lesson. Least Tern. Bill yellow, usually 

 tipped with black ; a white frontal crescent between cap and bill ; 

 shafts of two or more outer primaries black above ; mantle pale 

 gray; very small. L. 8 or 9. W. 6^. T. 3^. B. If E. U. S., 

 chiefly abundant coastwise. 



336. HYDROCHELIDON Boie. (iSap, water ; xeXiSmi', swallow.) 



667. H. nigra (L.). Black Tern. Head, neck and under parts 

 black (in full plumage) ; wings and tail above dark like the back ; 

 crissum white. L. 10. W. 8. T. 3^. B. 1^^. N. Am., chiefly 

 inland. (Eu.) The American var. surinamensis (Gmelin) is 

 darker than the European form. 



Family CXXIX. RHYNCHOPID^. (The Skimmers.) 



Gulls with the lower mandible much longer than the upper, com- 

 pressed like a knife-blade ; its two sides completely soldered to- 

 gether ; the upper edge as sharp as the lower, and fitting in a 

 groove in upper mandible; tip of bill obtuse; upper jaw com- 

 pressed, movable at base ; tongue very short, stumpy. Wino-s very 

 long. Otherwise similar to the terns. One genus, with 3 species. 



337. RHYNCHOPS Linnjeus. {piyxos, beak; &-<^, face.) 



668. R. nigra L. Black Swimmer. Cutwater. Glossy 

 black ; white below ; lower mandible about an inch longer than 

 upper. L. 1 7 to 20. W. 15. T. 5, sharply forked. ° B. 2|. 

 Tropical Amer., N. to N. J., abundant southward. 



Order XXXIII. TUBrN"ARES. (The Tube-nosed 



Swimmers.) 



Nostrils tubular; bill with the upper mandible hooked, its cover- 

 ing composed of several pieces separated by deep grooves. Other- 

 wise essentially like the Longipennes so far as external characters 

 are concerned. 

 a. Nostrils united in a double tube, placed horizontally on the cnlmen. 



PUOCELLAKUD.E, 130. 



