LIFE HISTORIES OF NORTH AMERICAN DI\aNG BIRDS. 199 



pursuit. The presence of dead birds about the rookeries indicates 

 that deadly combnts may sometimes occur. 



Winter. — During mild winters the Pallas's murres often spend 

 the winter not far from their summer homes in the southern por- 

 tion of Bering Sea, but they ordinarily winter about the Aleutian 

 Islands, where the water is usually open, or on the North Pacific 

 Ocean. It is interesting to note in this connection that, whereas the 

 Briinnich's murre winters much farther south than the common 

 murre on the Atlantic coast, the Pallas's murre winters much farther 

 north and apparently not far from its breeding range. 



DISTRIBUTION. 



Breeding range. — Coasts and islands of the North Pacific, Bering 

 Sea, and western Arctic Ocean. From Kodiak, the Aleutian and 

 the Commander Islands northward throughout Bering Sea; and in 

 the Arctic Ocean from Wrangel and Herald Islands, and Koliut- 

 schin Island, Siberia, to Kotzebue Sound and Cape Lisburne, Alaska. 

 Recorded in summer from Kamtschatka, Kurile Islands, and Japan 

 (Yezzo), where they probably breed. 



Winter range. — The open sea about the Aleutian and the Com- 

 mander Islands, and probably along part of the coast of southern 

 Alaska to Seymour Narrows and to southern Japan. In favorable 

 seasons birds occur north to the Pribilof Islands. 



Spring migration. — Birds arrive on their breeding grounds, Bo- 

 goslof Island. April 26; Pribilof Islands, April 1 (first taken) ; St. 

 Michael, last of May (sometimes earlier) ; Kotzebue Sound. Cha- 

 misso Island, June 6; Point Hope, April 14 (earliest). 



Fall migration. — Birds leave their nesting places in Bering Sea, 

 beginning in August, but the colonies are not deserted until the mid- 

 dle of September or later. 



Egg dates. — Bering Sea Islands: 25 records. June 2 to September 

 1 ; 13 records, June 18 to July 12. North of Bering Strait: 7 records, 

 July 3 to August 8; 4 records, July 6 to August 1. South of Alaska 

 Peninsula : 6 records. June 10 to 26; 3 records. June 18 to 24. 



ALGA TORDA Linnaeus. 



RAZOR-BILLED ATJK. 



HABITS. 



Far oif to the southward of Grand Manan Island an outlying 

 group of rocky islands, the Murre Ledges, mark the entrance to the 

 Bay of Fundy. The outermost and southernmost of these is known 

 as Yellow Ledge ; it is a low, flat rocky island, about half an acre in 

 extent at high tide, and is covered with a mass of loose rocks and 

 bowlders. Here on June 17, 1891, I first made the acquaintance of 



