VOL. VI.] BRITISH LESSER BLACK-BACKED GULL. 3 



Moreover, the difference can be as easily appreciated 

 when individual specimens of the two races are com- 

 pared as when the two races are examined in series. 



Other distinctive features are by no means so marked 

 as the above ; but as far as the few measurements which 

 I have been able to make would seem to indicate, males 

 of the light-backed or British race have rather shorter 

 wings and longer and stouter bills than the dark-backed 

 or Scandinavian race (c/. measurements in list at end). 

 I make this statement, however, with reserve, for a good 

 many birds examined were not sexed, and the bills may 

 vary considerably with age, so that a very much larger 

 series is necessary before any very definite conclusion on 

 this point can be arrived at. 



The same relative proportions seem to obtain in female 

 specimens, whose bills are considerably smaller than in 

 the male. 



Apart from these latter considerations, however, I 

 have no hesitation in separating the British Lesser Black- 

 backed Gull under the name of 



Larus fuscus britannicus.* 



The types, both male and female, are preserved in the 



British Museum collection at South Kensington : — 



Type <? Caithness (86.7.9.1). Summer plumage. Coll. Col. 



Irby. Measurements : Wing, 17 in. (432 mm.) ; 



exposed culmen, 2,10 in. (54 mm). 



* Under the name of Lams graellsii, Brehm in 1857 described (Allge- 

 meine Deutsche Naturh. Zeitung, 1857, p. 483) an example of the 

 Lesser Black-backed Gull which was taken in Malaga harbour (Spain) ; 

 and as the British light-backed race may wander in winter to the 

 western Mediterranean (c/. text below) the question of course arises, 

 should it be known under the name of Larus graellsii. My opinion is 

 that this name cannot stand. Brehm' s diagnosis is as follows : " Laro 

 fusco similis, sed multo major, rostro multo crassiori et colori valde 

 clariore." This description may possibly stand for a race which 

 breeds on the Moroccan coast (e.g. Island of Alboran) or along the shores 

 of the Mediterranean, but it certainly cannot stand for the British race, 

 which is characterized by having the wings smaller than in L. fuscus 

 fuscus, not " much larger " as in Brehm's diagnosis of L. graellsii. We 

 are also left in doubt as to whether it is the colour of the bill which is 

 " valde clariore," or whether it is the Gull itself. The type, too, is 

 missing, so that with such uncertainty as to the particular race which 

 Brehm was describing, 1 think there is nothing for it but to find a new 

 name for the light-backed British race. 



