LARIDyE — THE GULLS AND TERNS — STERNA. 



275 





— one was certainly obtained in the Galapagos, and not within our limits ; and as 

 the expedition that procured the supposed Californian example visited the same 

 group, Jlr. Salvin is of the opinion that this was tlie locality from which both speci- 

 mens came, and that this bird does not belong to the faujia of the United [States. 



Genus STERNA, Linn.eus. 



Stcrm, Li\N. S. N. ed. 10, I. 1758, 137, eJ. 12, I. 17C6, 227 (type, by eliiii., SUrmi hirundo, Linn.). 



Stenudii, liciii:, Isis, 1822, 503 (type, Sterna minula, Lin;;.). 



Thalassms, BoiE, Isis, 1822, 503 (type, Stcriui caspiii, Pali..). 



Thalassca, KAur, Sk. Kiitw. Eur. Tliierw. 1829, 97 (type, Slcrna paradiscir, Bkunn.), 



Sijloclu'lidun, BiiiciiM, Viig. Deutschl. 1830, 767 (tj'pe, Sterna cu-tpia, Linn.). 



ActochclidoH, Kaup, .Sk. Eiit. Eur. Thienv. 1829, 31 (type, Sterna cant iitai, G.Mia,). 



GcloclicUdon, Biikii.m, Naturg. Vbg, Deutschl. 1831, 774 (type, O. mcridimalis, UiiEim, Sterna, 



anglica, Mont.). 

 Haliplana, Waol. Isis, 1832, 1224 (type, Sterna fulujinosa, Gmel. ). 



Char. Size exceedingly v.iriuLle, the form and colors less so ; tail alwaj's decidedly forked, 

 and toes almost fully webbed, but tlie webs concave, or " scalloped out," anteriorly. 



■II. 



Synopsis of North American Species. 



Ai Size medium (wing about 11.75-12.25 inches) ; tail eniarginate ; occipital fealliers .«oft and 

 blended ; inner webs of primaries bicolored (a blackish stripe ne.\t the shaft, the inner 

 border broadly white) ; bill wholly black, short and thick, its upper and lower outlines 

 strongly convex, the depth through tlie base about one third the length of the culnien ; 

 pileum entirely black in summer, uniform ashy white in winter. (GdochcUdim, Buehm.) 



1. S. anglica. Bill and feet black : above, pale pearl-blue, including the runiis upper tail- 



coverts, and tail ; beneath, entirely white. Wing, 11.75-12.25 inches ; tail, 5.50 ; culnien, 

 1.40 ; tai"su9, 1.30 ; middle toe, 1. 10. Hah. Eastern coast of North America, and various 

 parts of the Old World. 

 Bi Size very large (wing 15.(K) inches or more) ; tail emarginate ; occipital feathers soft and 

 blended, not forming a crest ; inner webs of primaries concolored (dusky grayish) ; adult, 

 above, pale pearl-gray, beneath, white ; hood wholly black in summer, wholly streaked or 

 speckled with white in winter. (Thalasseus, BoiE.) 



2. S. caspia. Bill very robust (the depth through the base a little less than one third the 



length of the culmen), deep red. Hah. North America in gimeral, and various pai'ts 

 of the Old World. 

 C Size large or medium (wing 12.50-15.00 inches) ; tail deeply forked ; occipital feathers pointed 

 and somewhat lengthened, forming a short but distinct cre.st ; inner webs of primaries 

 bicolored (dusky in a well-defined stripe next the shaft, the iuiier edge broadly and 

 abruptly white) ; adult, pale pearl-gray above, white beneath ; jiileum wholly black in 

 spring, the forehead, lores, and centre of the crown white in breeding-season, (^Adochel- 

 idon, Kaup.) 



3. S. maxima. Bill stout (depth through the base much less than one third the length of 



the culnien), deep orange ; wing, 14.00-15.00 inches. Hah. Coasts and inland waters 

 of Middle and Southern North America, north to about 40''. 



4. S. elegauB. Bill very slender (depth through the base about one fifth the length of the 



cidmeii), deep orange-red ; occipital feathers much elongated, and lower parts deeply 

 tinged with peach-iilossom pink. Wing, about 12.50 inches. Hub. Pacific coast of 

 Middle America, north to California. 



5. B. sandvloenais. Bill very slender, as in S. clegam, but deep black, tipped with yellow ; 



occipital feathers less elongated, and lower parts without jiink tinge. Wing, about 12.50 

 inches. Hab. Atlantic coast of North, and both coasts of Middle, America ; Paltearctic 

 Region. 



