542 Dwight, Larus fuscus and Larus affinis. [q^ 



THE RELATIONSHIP OF THE GULLS KNOWN AS LARUS 

 FUSCUS AND LARUS AFFIX IS. 



BY JONATHAN DWIGHT, M. D. 



Plates XX and XXI. 



\n approaching many of the problems in modern systemic 

 ornithology, one is confronted with the necessity of steering a 

 middle course between the Scylla of imperfect knowledge on the 

 one hand and the Charybdis of nomenclature on the other. Either 

 may bring us to shipwreck; but mindful of those who have pre- 

 ceded me in writing about the Lesser Black-backed Gull (Larus 

 fuscus), and the Siberian Gull (Larus affinis), I venture with some 

 hesitancy to take up the tangled question of the relationship of 

 these birds and make another endeavor to fix the proper names 

 upon them. 



Larus fuscus, an abundant European species, was described in 

 1758 by Linnaeus, and has never been taken on the American side 

 of the Atlantic. L. affinis, however, has stood as a North American 

 species in the A. O. U. ' Check-Lists ' on the strength of a single 

 specimen, the type taken in southern Greenland and described 

 by Reinhardt in 1853 (Videnskab-Meddel, p. 78). 



Until 1912 these two gulls were recognized as two full species, 

 and then Lowe (Brit. Birds, VI, no. 1, June 1, 1912, pp. 2-7, pi. 1) 

 started the ball rolling by restricting the name fuscus to Scandi- 

 navian birds and describing the paler bird of the British Isles 

 subspecifically as brittanicus. A few months later Iredale (Brit. 

 Birds, VI, no. 12, May 1, 1913, pp. 360-364, with pi.), borrowing the 

 type of affinis from the Copenhagen Museum, where it had rested 

 for half a century, and comparing it with British specimens, found 

 it to be identical with them; but not content with synonymyzing 

 brittanicus with affin is, he reached the conclusion that the Siberian 

 bird was larger and therefore required a new name — antelius. 

 In 1915 Buturlin (Mess. Orn. VI, no. 12, 1915, p. 149) scored 

 Iredale for not providing either type or type locality for antelius, 

 and went on to say that he himself had given the name Larus 



