away in full flight, pursued for a time by the victor. He quickly re- 

 turns, however, and springing into the air from the original knoll 

 again sends out his cry of defiance to all comers. During the last 

 half of May along the coast of Bering Sea these ptarmigan are notice- 

 able everywhere, and the air is filled with their loud insistent notes. 

 A little later, when the mating is over and the females are hidden 

 away on nests, the males completely lose their boisterous pugnacity, 

 and are almost as quiet and inconspicuous as their mates. 



Additional Notes by the Editor 



A few explanatory notes, largely derived from Mr. Nelson's valu- 

 able and interesting Report, may be added to the foregoing lively ac- 

 count of the bird-life of the Alaskan tundras. 



The loons of this district are of five different species, namely, 

 the widely distributed "common loon," or great northern diver ; the 

 yellow-billed ; the black-throated ; the Pacific ; and the red-throated 

 loon. They are distinguished chiefly by their varying colors about 

 the head and neck. In the common loon the black head and neck are 

 in summer deep black, crossed on the throat by a bar or by transverse 

 streaks of white; in the Pacific species the top of the head and the 

 hind neck are pale, smoky gray, the throat and fore neck glossed with 

 bronzy green or purple; in the black-throated loon the head and 

 neck are deep leaden gray above, and are glossed beneath with velvety 

 purple ; and in the red-throated the fore neck in summer is rich chest- 

 nut in color. This last is the smallest of the lot. The largest of the 

 loons is the yellow-billed, whose head and neck are glossed with 

 violet-blue. The habits, nests, and eggs of all are similar. The eggs 

 number two, and are of an elongated oval form, deep brown or olive 

 in tint, and sparsely speckled. 



The black guillemot mentioned is a circumpolar species belong- 

 ing to the Arctic sea-front and islands, and rarely seen south of 

 Kotzebue Sound. 



The jaegers, or skuas, as they are more often termed in the North- 

 Atlantic region, are wide-wandering oceanic gulls of predatory habits, 

 that get their living mainly by robbing their smaller brethren. They 

 are large, and exceedingly swift and powerful on the wing. The 

 Eskimos attribute to the parasitic jaeger remarkable prowess, and call 

 it "the cannibal" because, as they say, it formerly captured and ate 

 men. This jaeger is far more agile and bold than the pomarine, which 

 it will drive from its neighborhood ; but it is not so graceful in flight 

 as the long-tailed one. They harry the gulls and terns to make them 

 disgorge fish just caught, and then swoop down beneath the falling 



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