164 MR. H. SAUNDERS ON THE LARIN.S. [Feb. 5, 



Larus torquatus et Larus gavia, Pallas, Zoogr. Rosso-As. ii. pp. 

 328, 329 (1811). 



Gavia tridactylus, Boie, Isis, 1822, p. 563. 



Rissa brunnichii, Stephens, ex Leach, in Shaw's Gen. Zool. xhi. 

 pt. i. p. 181, pi. 21 (182")), type of genus Rissa. 



Ckeimonea tridactylus, Kaup, Nat. Syst. eur. Th. pp. 84, 196 

 (1829), type of genus Cheimonea. 



Laroides tridactylus, Brehm, Vog. Deutschl. p. 754 (1831). 



Laroides rissa, id., op. cit. p. 755 (1831). 



Laroides minor, id., op. cit. p. 756 (1831). 



Rissa cinerea, Eyton, Cat. Brit. B. p. 52 (1836). 



Rissa tridactyla, Macgill. Man. Brit. B. ii. p. 249 (1842) ; Hist. 

 Brit. B. v. p. 515 ; Gray, Gen. Birds, iii. p. 655 (1849); Bruch, J. 

 f. Orn. p. 103 (1853) ; Bp. Consp. Av. ii. p. 225 (1857). 



"Rissa brachyrhynchus (Gould)," Bruch, J. f. Orn. 1853, p. 103, 

 nee Gould. 



Rissa borealis et gregaria, Brehm, Naum. 1855, p. 294. 



"Rissa niveus (Pall.)," Bruch, J. f. Orn. 1855, p. 285, nee Pallas. 



Rissa kotzebui, Bp. Consp. Av. ii. p. 226 (1857). 



Larus (Rissa) tridactylus, Coues, B. N.W. Am. p. 644 (1874). 



Larus tridactylus, var. kotzebui (Bp.), ibid. p. 646 (1874). 



Hab. Arctic region, and along the sea-coasts of the subarctic 

 region, down to about 40° N. lat., breeding perhaps even in the 

 Canaries (Godman) ; in winter it is abundant about the Azores, 

 Canaries, and opposite coast of Africa. In America it is found on 

 both Atlantic and Pacific coasts, but does not seem to extend far 

 down the latter, nor to Japan or China even in winter. 



In treating of the genus, I have already noticed that examples 

 are occasionally found about Alaska and the Aleutian Islands with 

 a minute but tolerably developed hind toe, and, at times, with a 

 visible nail, a variation which is rare and not always equal in extent, 

 even on both feet of the same individual. I have therefore treated 

 var. kotzebui as a synonym, there being no other difference between 

 this and the ordinary Kittiwake, and a gradation between them 

 existing. 



3. Rissa brevirostris, Brandt. 



Larus brachyrhynchus, Gould, P. Z. S. 1843, p. 106; Zool. Voy. 

 of "Sulphur," p. 50, pi. 34 (1844), nee Richardson (1831). 



"Rissa nivea (Pall.)," Gray, Gen. Birds, iii. p. 655 (1849), nee 

 Pallas ; Lawr. B. N. Am. p. 855 ; Elliot, B. N. Am. pi. 54. 



"Rissa brevirostris, Brandt," Bruch, J. f. Orn. 1853, p. 103; 

 id. 1855, p. 285: Dall and Bann. Tr. Chic. Ac. i. 1869, p. 305. 



"Gavina citrirostris, Schimper," Bruch, J. f. Orn. 1855, p. 284 

 (Kamtschatka). 



Rissa brachyrhyncha, Bp. Consp. Av. ii. p. 226 (1857); Coues, 

 P. Ac. N. Sc. Philad. 1862, p. 306. 



Larus warnecki, Coinde, Rev. et M. Zool. 1860, p. 401 (Aleutian 

 Islands). 



