PYGOPODES. 363 



which Steller observed on the coasts of the Kurile Islands (Pallas, 

 Zoogr. Rosso-Asiat. ii. p. 341) belonged to the species with a large 

 white bill, and not to the perfectly distinct species with a much 

 smaller black bill. It is to the white-billed species that the Kamt- 

 schatkan birds must be referred (Stejneger, Orn. Exp. Comm. Isl. & 

 Kamtschatka, p. 14) ; and it is the White-billed Diver that has 

 occurred on the Japanese coasts. The occurrence of this species in 

 Japan was first ascertained from an example procured by Captain 

 Blakiston at Hakodadi in January (Swinhoe, Ibis, 1877, p. 146) ; 

 and I have a fine example collected by Mr. Henson at Hakodadi 

 (Seebohm, Ibis, 1884, p. 32). It has also occurred as far south as 

 Nagasaki (Saunders, Ibis, 1883, p. 348). 



The White-biUed Diver is probably a circumpolar species, and 

 breeds in Siberia and Arctic America; it occasionally visits the 

 British Islands in winter. 



369. COLYMBUS ARCTICUS. 

 (BLACK-THROATED DIVER.) 



Coh/mbus arctieus, Linneus, Syst. Nat. i. p. 221 (1766). 



In this species the forehead and crown are uniform unmottled grey 

 at all ages and seasons ; and the height of the bill at the nostrils 

 never reaches f of an inch. 



Figures : Gould, Birds of Great Britain, v. pi. 44 ; Dresser, Birds 

 of Europe, viii. pi. 627. 



The Black-throated Diver is a common winter visitor to the coasts 

 of Yezzo (Whitely, Ibis, 1867, p. 208), and probably of all the other 

 Japanese Islands. In the Pryer collection there are five examples in 

 winter plumage from Yokohama, and I have an example in summer 

 dress collected by Captain Blakiston in May (Seebohm, Ibis, 1879, 

 p. 22). Mr. Ringer has also procured it near Nagasaki, where the 

 examples obtained by tlie Siebold Expedition were probably also 

 procured (Temminck and Schlegel, Fauna Japonica, Aves, p. 123). 



The range of the Black-throated Diver extends from the British 

 Islands, across North Europe and Siberia to Japan, and across 

 Bering Straits into Alaska and Arctic America as far east as 

 Hudson^s Bay. 



It is impossible to say whether any of the examples belong to the 

 form which American ornithologists call Colymbus arcticus pacificus. 



