86 ANNALS OF SCOTTISH NATURAL HISTORY 



from other stations, in the nests of the Common, or Arctic Terns, on 

 the Fame Islands, but I am not aware that the experiment has been 

 attended with success. 



SABINE'S GULL, Xema sabinii (Joseph Sabine). No record for 

 the district. A young bird, shot three miles off North Berwick, on 

 2nd October 1877, is recorded by the late Mr. Robert Gray, and is 

 in the possession of Dr. Crombie of that town. (" Hist. Berw. 

 Nat. Club," vol. viii. p. 355.) 



LITTLE GULL, Larus minutus, Pallas. Occurs as an occasional 

 visitant in autumn, or winter, upon the Northumberland coast, and 

 has frequently been obtained about Dunbar, and in the Firth of Forth. 



Two specimens are recorded from Coldingham Loch : one in 

 December 1869, and the other on i6th August 1877. 



BLACK-HEADED GULL, Larus ridibundus, Linnaeus. An abundant 

 resident, present about the harbour at all seasons, but of course 

 most numerous from autumn to spring. 



Notwithstanding all that has been written to the contrary, I have 

 not the slightest hesitation in saying that here, at any rate, the 

 assumption of the black head in spring is due to a regular moult, 

 and not to any actual change in the colour of the feathers them- 

 selves ; and a similar moult from black to white takes place in 

 autumn. I have examined many gulls with a view to establishing 

 this fact, and every specimen killed at the seasons of change has 

 shown unmistakable evidence of moulting. This renewal of the 

 feathers on the head is not even peculiar to the Black-headed Gull, 

 for several, indeed most, of the other common species undergo a partial 

 moult of those parts at the same seasons. While it is almost, if 

 indeed not altogether, impossible to suppose that many of the state- 

 ments, which have been published to the contrary, can have been 

 made upon anything short of absolute proof, it is yet very difficult 

 to believe that the change is brought about by a moult in some 

 cases, and by a change in the colour of the feathers themselves in 

 others. 



The black hood is assumed very early in the year by some 

 individuals. I have more than once seen it here apparently com- 

 pleted by the second week in January, and by the middle of 

 February it becomes quite common. I have also upon two or 

 three occasions seen specimens, which still retained the black band 

 upon the tail, and a few of the brown feathers of immaturity about 

 the scapulars, but which had attained perfect black heads. One 

 instance of this occurred at Barrow Lake, in Northumberland, in 

 May 1894, when many of the nests contained eggs, and the gull in 

 question was apparently a breeding bird. 



Several small examples of this species, corresponding in size to 

 the Masked Gull, Larus capistratus, of some authors, have been seen 

 or obtained here. 



