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THE LESSER BLACK-BACKED GULL OF THE 



BRITISH ISLES. 



Larus fuscus hritannicus, subsp. nov. 



BY 



PERCY R, LOWE, b.a., m.b., m.b.o.u. 

 [Plate 1.] 



It is, I think, safe to say that most British ornithologists 

 would not have hesitated to assert that the Lesser Black- 

 backed Gull of our islands was the Larus fuscus of Linnaeus. 

 Yet the fact remains that the Lesser Black-backed Gull 

 of the British Isles is perfectly distinct from the gull 

 described by Linnaeus under the name of Larus fuscus ; 

 and no ornithologist could have the least difhculty in 

 recognizing the fact were he to compare a series of speci- 

 mens from the type-locality with a series of our own 

 native bird. 



The fact that the difference has never been noted before 

 can only be due, I presume, to " taking things for granted," 

 and to that frequent cause of the perpetuation of inac- 

 curate information which may be summed up in the phrase 

 " never looking." 



Linnaeus in his Systema Naturae, ed. X., 1758, p. 136, 

 first described the Lesser Black-backed Gull from Sweden. 

 The mantle, scapulars, and wing-coverts of breeding 

 birds from Sweden or Norway are characterized by a 

 coloration which varies from a dark, slaty-black in the 

 freshly-moulted spring-feathers, to a sooty or deep 

 brownish-black with the advance of summer and conse- 

 quent fading. If now we examine a series of breeding 

 birds from the British Isles in corresponding summer- 

 plumage, we find that the same parts are of a clear, slaty- 

 grey colour, and nothing like so dark as the above ; and 

 this difference in both depth and character of coloration 

 is so constant and well marked, that it can be recognized 

 at the merest glance and without a moment's hesitation 

 (c/. Plate 1). 



