278 OAVi.K. 



breed in some numbers on tlie clifls of Kodushima, one of the Seven 

 Islands (Stcjncger, Proc. United States Nat. Mus. 1887, p. 482). 



It is a very rare bird, and has only occurred elsewhere on the 

 opposite shore of the Pacific south of Vancouver Island. 



273. ALCA MARMORATA. 



(MARBLED GUILLEMOT.) 



Colymhus mannoratwi, Gmelin, Syst. Nat. i. p. 583 (1788). 



The Marbled Guillemot may be distinguished from all its Japanese 

 congeners by its combination of the two characters — scapulars streaked 

 uit/i while (winter) or huff (summer), and no ivhite on Ihe upper 

 surface of the unnys (wing-covcrts, or tips of secondaries) . 



Figures : Latham, Gen. Syn. iii. pt. ii. pi. 90 ; Audubon, Orni- 

 thological Biography, v. pi. 430 ; Audubon, Birds of America, vii. 

 pi. 175. 



Although the Marbled Guillemot was known both to Pallas and 

 Latham, I can find no record of its occurrence cither in the Kurilc 

 Islands or in Japan earlier than that of the female in the Swinhoe 

 collection, which was procured in May by Captain Blakiston at 

 Hakodadi (Swinhoe, Ibis, 1874, p. IGG). There is a male in the 

 Swinhoe collection apparently procured at the same time, but it is 

 in full summer plumage, whilst the female is only beginning to lose 

 its winter dress. I liavc another male collected by Mr. Henson at 

 Hakodadi on the 23rd of March, which has half completed its spring 

 moult, and a female collected by Captain Blakiston at Hakodadi in 

 November in full winter plumage. I have a female collected by 

 Mr. Snow on the Kurilc Islands in which the feathers of the upper 

 parts arc tipped with greyish white instead of dark buff, and the 

 under wing-coverts are mottled with grey instead of being all grey. 

 Mr. Owston has collected this species at Yokohama (Hlakiston and 

 Prycr, Trans. As. Soc. Japan, 1882, p. 90). 



The breeding-range of the Marbled Guillemot extends eastwards 

 from the Kurilc Islands across the Aleutian chain and the islands on 

 tlie south coast of Alaska as far south as Vancouver Island. It is 

 not known to occur north of the Aleutian Islands. 



Hr. Stejnegcr divides the ^Marbled Guillemot into tM'o species, 

 which he calls Brachijrhaniphus murmoratiis and B. ])erdix ; the former 

 is probably the male and the latter the i'emale or immature male. 



