LARID.E — THE GULLS AND TERNS — HYLROCHELLDON. 323 



Hydrochelidon leucoptera. 



THE WHITE-WINGED BLACK TERN. 



Sterna leucoptera, Meisnkr & Schinz, Vog. Schweiz, 1815, 264. 



Hydrochelidon leucoptera, Boie, Isis, 1822, 563. — Saunders, P. Z. S. 1876, 641. — Ridgw. Nom. 



N. Am. B. 1881, no. 694. — Coues, 2d Check List, 1882, no. 807. 

 Hydrochelidon nigra, Gkay, Gen. B. III. 1849, 660 (not Sterna nigra, Linn.). — Coues, B. N. W. 



1874, 709. 

 Hydroclie/idon sublcucoptcra, Breiim, Vogelfang, 1855, 350. 



Hab. Palaaretic Region, Africa, Australia, and New Zealand. Casual or accidental in Eastern 

 North America (Wisconsin ; Kumlien). 



Sp. Char. Adult, in summer : Head, neck, and lower parts, except anal region and crissum, 

 uniform sooty black, deeper black on the head and neck ; back, scapulars, tertials, and upper part 

 of rump plumbeous ; wings silvery gray, becoming gradually white on the anterior lesser coverts. 

 Lower part of rump, and upper tail-coverts, white, sometimes tinged with bluish gray ; tail gray- 

 ish white or pale grayish, the feathers tinged with deeper grayish toward ends. Anal region and 

 lower tail-coverts pure white. Lining of the wing, and axillars, dark plumbeous. Bill dark 

 brownish ; iris dark brown ; legs and feet pale brownish, in the dried skin. 



Wing, 7.60-8.20 inches (average, 7.99) ; tail, 2.80-3.25 (3.06) ; culmen, .90-.95 (.94) ; depth of 

 bill through base, .20 ; tarsus, .70-.75 (.71) ; middle toe, .60-.65 (01). [Four specimens.] 



The single American specimen examined (the only one known — No. 66213, $> ad., Lake Kos- 

 konong, Wis. ; Th. Kumlien), has the wing and tail much shorter than either of the three 

 European specimens, measuring, respectively, only 7.60 and 2.80 inches against 8.00 and 3.00 — 

 the minimum of the same measurements in the European examples. 



The occurrence of a single specimen of this well-known European species within 

 the limits of the United States is an interesting incident of comparatively recent 

 occurrence. It was taken by Ludwig Kumlien, the son of the well-known ornitholo- 

 gist, Professor Thure Kumlien, on Black-hawk Island, Koskonong Lake, July .">. L873. 

 It was a female, apparently breeding, and flying in company with a flock of the common 

 Black Tern. The eggs in its ovaries were as large as No. 6 shot. 



In Europe this species is a common companion of H. nigra, ami rather a southern 

 species than a northern one. It is of only occasional occurrence in Great' Britain, 

 and is merely accidental in Sweden, in both of which countries the Black Tern is 

 comparatively common. Mr. Wheelwright states that only a single example of this 

 species has been seen in South Sweden. A solitary specimen was shot on the Shannon 

 River in 1841 ; this was supposed to be a form of the Black Tern, and was for 

 a while so labelled in the museum of the Dublin Natural History Society. Another 

 specimen was shot near Yarmouth, England, May 17. 1853. According to Temminck, 

 this Tern inhabits the bays and inlets of the shores of the Mediterranean, and is very 

 common about Gibraltar. It visits also the lakes, rivers, and marshes of the countries 

 in the vicinity of the Alps. It is said to be very common about the lakes of Lucamo, 

 Lugano, Como, Iseo, and Garda, and is occasionally seen on the Lake of Geneva. 

 It is included by Dr. Schinz among the birds of Switzerland, and has also been 

 procured in France and Belgium. Brehm includes it in his work on the Birds of 

 Germany, and Nilsson in his Fauna of Scandinavia, as a very rare straggler; and 

 Savi and Malherbe give it as a bird of Italy. Mr. Drummond met with it in Northern 

 Africa, near Tunis. It is said to be common in spring in Dalmatia. Its habits do 

 not appear to differ essentially from those of its near relative. If nigra. 



Its occurrence in the Transvaal, in Africa, renders it probable that this species 

 may be more or less generally distributed over the whole of that continent. Mr. T. 



