The White-Winged Black Tern — Hydrochelidon Leucoptera (Schinz)
This species, which is nearly allied to the preceding, breeds in the marshes of Central and South-eastern Europe. It is a very scarce and irregular visitor to our eastern and south-eastern shores, especially in spring.
In habits it resembles the Black Tern, from which it may be distinguished in summer by its red bill, white tail and tail coverts, and whitish wing coverts. The young may be distinguished from those of H. nigra by their longer toes and much paler rump and tail. Length 9·5 in.; wing 8·25 in.