308 MR. II. SEEBOUM ON THE BIRDS NORTH OF ALASKA. 
Larus ROSSI. The expedition was fortunate enough to obtain 
more examples of Boss’s Gull than were previously known to exist 
in all the museums of the world put together. They were 
very abundant, on migration, from the last week of September to 
the last week of October, principally young birds flying north-east. 
Larus kumlieni. This was probably a young Larus affinis, as 
it is described as small, dark, and immature. 
Larus glaucus. The Glaucous Gull arrived early in May, but 
its eggs were not found, though it was seen during the summer. 
Larus eburneus. A few examples only of the Ivory Gull were 
seen, but none secured. 
Stercorarius pomarinus. The Pomarine Skua was the least 
common of the three species, but a regular summer visitor. 
Stercorarius richardsoni. Eichardson’s Skua was commoner 
than the last mentioned species. 
Stercorarius buffoni. Buffon’s Skua was by far the most 
abundant of the three species, and arrived late in May. They 
leave late in August. 
CoLYMBus SEPTENTRiONALis. The Eed-tlii’oated Diver was very 
common, and its eggs were procured. 
CoLYMBUS ARCTicus PACiFicus. The Pacific form of the Black- 
throated Diver arrived early in June, and was common. 
CoLYMBUs ADAMSi. The White-billed Diver arrived about the 
end of May, and remained during the summer. 
Alca grylle. The Black Guillemot was a resident as long as 
any open water was to be found. 
Alca troile arra. This Guillemot is an intermediate form 
between the Common and Briinnich’s Guillemots. It was a 
somewhat rare straggler. 
Grus canadensis. The Little Crane was a rare straggler. 
Cygnus AMERiCANUS. Swans were occasionally seen, but none 
secured. 
Anser iiyperboreus. The Lesser Snow Goose was occasionally 
seen from the middle of May to the end of June. 
Anser albifrons gambeli. TheAmericanWhite-frontedGoo.se 
was first seen May IGth, and were very abundant. Great numbers 
are secured by the Eskimo when they are moulting and are unable 
to fly. The nest is always placed on the “ black tundra,” and 
lined with moss and down. 
