208 ) 



ON BIRDS REPRESENTED IN THE BRITISH 

 ISLES BY PECULIAR FORMS. 



BY 



EENST HARTERT, Ph.D. 



As late as 1892, A. R. Wallace accepted only three birds 

 as peculiar to the British Isles {Island Life, second ed., 

 p. 840) ; the same number was admitted by Howard 

 Saunders in 1899 (^III. Manual of Brit. Birds, second 

 ed.). The former author quoted " Parus ater, suh.sp. 

 britannicus,'^ " Acredula caudata, suh.sp. rosea,'^ and 

 " Lagopus scoticus" while Mr. Saunders only distinguished 

 by special names " Motacilla lugubris, Motacilla raii, 

 Lagopus scoticus," not even separating' the Long-tailed 

 Titmouse. 



Mr. Dresser, in his "Manual of Palsearctic Birds," 

 1902, added to the three allowed by Mr. Saunders, 

 " Acredula rosea " (though he partially united it with the 

 continental em'opcea — cf. "Vog. pal. Fauna," I., p. 384 — and 

 consequently gave it too wide a range) and " Parus 

 hritaymicus.^'' This was undoubtedly a step forward, but 

 recent investigations have shown that over twenty British 

 breeding birds are separable from their continental allies. 



In the following article I have given short notes on 

 twenty-one forms more or less strictly peculiar to 

 the British Islands. It may be that the characters of 

 one or two of these will not be found constant enough 

 to recognize them as different, but all the others are easily 

 separable, and must undoubtedly be considered as 

 geographical representatives of continental forms. There 

 can hardly be any doubt that one or two more will be 

 found to differ, when carefully compared, so that the 



