NATATORES. 381 



5. Larus glaucotes, Meyen. 



Larus glaucotes, Meyen, Nov. Act. 1834, p. 115. 

 Larus maculipenms, LiCHT. Verz. p. 83 (1823) ? 



" Xema cirrocephulum, Gr. R. Gray," Peale, Zool. U. S. Exp. Exp. Birds, p. 289 

 (1848). 



Nov. Act. Acad. Caes. Leop. 1844, Plate XXIV. 



Very probably Lichtenstein's species, as above cited, and a common 

 bird in collections from the coast of Chili. Our specimens measure, in 

 total length, about eighteen inches, being uniformly larger than those 

 of the preceding species. This species is stated by Mr. Peale to have 

 been obtained on the west coast of South America, as far north as 

 Peru. 



2. Genus STERNA, Linn. Syst. Nat. 1, p. 227 (1766). 

 1. Sterna frontalis, G. R. Gray. 



Sterna frontalis, Gray, Zool. Voy. Erebus and Terror, Birds, p. 19 (1845). 

 Sterna alhifrons, Peale, Zool. U. S. Exp. Exp. Birds, p. 279 (1st edition, 1848).* 

 Sterna striata, Gm. Syst. Nat. I, p. 609 (1788) ? 



Lath. Gen. Syn. Ill, Plate XCVIII? Zool. Voy. Erebus and 

 Terror, Birds, Plate XX. 



This species, so far as we can gather from the notes of the natu- 

 ralists of the Expedition, was observed only at New Zealand. In the 

 collection, we find adult specimens, presenting no peculiarities or 

 characters not mentioned in the description first above cited. 



* " Back and wings pearl-gray ; front, throat, neck, all the body, and tail, white ; 

 crown and occiput black ; bill black ; legs red ; claws black ; wings and tail equal ; 

 first primary longest, its outer web black ; tail forked ; all, excepting the two centre 

 feathers, pointed ; shafts white ; irides brown. 



"Total length fourteen and one-half inches; wings, from the carpal joint, eleven 

 inches ; tail six inches ; centre feathers two and six-tenths inches ; bill one and nine- 

 twentieths inches ; to the angle of the mouth two and one-tenth inches ; tarsi thirteen- 

 twentieths of an inch ; middle toe, including the nail, one inch ; nail three-tenths of an 

 inch." 



9C 



