WHITE-WINGED GULL, 571 



precision, but only in its summer plumage. A detailed 

 description of the bird in its mature and young states, in 

 winter plumage, was afterwards given, in the fourth volume 

 of the Memoirs of the Wernerian Society, by Dr. Edmondston, 

 in two separate papers, in the first of which, read on the 

 24th March, 1821, he introduces it as a new species, and in 

 the other, read on the 23d March, 1822, remarks definitively, 

 that although it might have previously been obscurely known, 

 it was now for the first time described as a British species, 

 and might be named Larus Islandicus, that name being both 

 designative of its " arctic haunts " and commemorative of the 

 " vulgar appellation by which it is known in the Zetland 

 Islands." In a paper read on the 8th March, 1823, in which 

 he alludes to an opinion long before adopted by him of there 

 being two species in Shetland to which the name of Iceland 

 is applied by the natives, " the one having to the other a 

 relation analogous to that which exists between the Greater 

 and Lesser Black-backed Gulls," he describes the Larus 

 leucopterus of the present article, and proposes transferring 

 to it from the larger species the name of Larus islandicus. 

 This species I afterwards described under the name of Larus 

 arcticus, which I conceived to be more appropriate, the bird 

 not being, in fact, known to breed in Iceland. Most authors, 

 unless when it suits a special purpose, take priority of name 

 as an established rule ; and if Dr. Edmondston first described 

 the bird in question, they would call it, as he has done, the 

 Iceland Gull. Others, discarding priority, would hold that 

 a naturalist, in naming an object, must describe it intelligibly, 

 otherwise his name cannot be adopted. Now, it is maintained 

 by M. Temminck that Faber made mention of it in 1820, 

 and gave a correct description of it in his Prodromus of the 

 Birds of Iceland, under the name of Larus leucopterus ; so 

 that, on the principles of both priority and intelligibility, 

 Faber's name ought to be adopted. Unless we were to give 

 the bird a more appropriate name than either islandicus or 

 leucopterus, I do not see how we can with propriety reject 

 the latter, even although the bird was unknown to the orni- 

 thologists of Great Britain and Ireland until they were 

 favoured Avith Dr. Edmondston's description of it. That 



