WHITE-WINGED BLACK TERN. 533 



remained there undistinguished till the present time. As 

 I believe this to be the first record of the occurrence of thi^ 

 bird in Britain, I subjoin a short description of the speci- 

 men and a sketch half the natural size, to assist in draw- 

 ing the attention of British naturalists to it, as it will 

 probably be found not unfrequent. 



"Measurement. Total length, to extremity of tail, 

 about eight inches ; bill from base ten lines and a half, 

 from rictus one inch five lines ; greatest depth of both 

 mandibles two lines and a half ; middle toe, including the 

 claw, eleven lines in length ; tarsus eight lines ; naked 

 portion of the tibia four lines. Colours. Legs and feet in 

 the preserved specimen pale yellow, probably red in the 

 living bird, claws darker ; bill dark blackish-brown ; head, 

 neck, breast, abdomen, under wing-coverts, and back deep 

 glossy black ; small wing-coverts, tail, and upper and 

 under tail-coverts pure white; first three quill -feathers 

 black, with a broad longitudinal band of white on the 

 inner webs ; remainder of the wings ash grey, becoming 

 darker towards the body." A second example has occurred 

 in Ireland. 



"The form, proportions, and size of this species are very 

 nearly those of the Black Tern, S. nigra ; like that species, 

 too, the webs of the toes are very deeply indented, being 

 reduced to a mere rudiment between the middle and inner 

 toes. The two species are, however, easily distinguished, 

 the under wing-coverts of the 8. nigra are white, of the 

 S. leucoptera black ; the tail of the former is dark grey, 

 of the latter pure white ; in the S. nigra the throat is 

 white, breast and abdomen dark grey, and the back lead 

 colour, while in the S. leucoptera all those parts are black. 

 I speak of both species in their perfect plumage." 



An example of this Tern, very rare as British, was 

 killed on the 17th of May, 1853, by Mr. Robert Risings, 



