28 NATUEAL HISTOEY COLLECTIONS IN ALASKA. 



ance, and tbeir climate is much more severe thau on the neighboring mainland. In winter they 

 are surrounded by the pack ice, and the summers are short and cold. Their general characteris- 

 tics, climate, and bird fauna really belong rather with the adjacent Siberian shore than the Amer- 

 ican. 



The belt bordering the Alaskan coast of Bering Sea belonging to this district is mainly low, and 

 much of it consists of broad marshy tracts but little above sea level. At intervals rise low mount- 

 ainous masses a few hundred feet high, producing bald headlands when they occur on the 

 coast. Near Bering Straits the coast becomes more uniformly hilly. The country between the 

 mouths of the Yukon and Kuskosquim Eivers is the breeding resort of great numbers of water- 

 fowl. 



All of this district bordering on Bering Sea is barren of trees, bat along the courses of the 

 rivers and in sheltered spots on southern slopes of hills a more or less abundant growth of willows 

 and alders is found, which reach 8 or 10 feet in height in the Yukon delta. Bushes are also 

 large and plentiful about the head of Kotzebue Sound, but are more and more dwarfed and scat- 

 tering north of this point. 



The coast country south of Bering Straits is mainly rolling and covered with a mat of vege- 

 tation consisting of a bed of sphagnum mosses, interspersed and overgrown with various grasses 

 and flowering plants. The low country near the Yukon mouth is cut up by tide creeks, lagoons, 

 ponds, and small water-courses. 



The bottom of the sea all along this part of the coast slopes very gradually from the shore, 

 and is constantly being brought nearer the surface by the vast deposit of mud brought down 

 each year by the Yukon and Kuskoquim Eivei-s. In consequence of the shallow sea and the enor- 

 mous amount of warm fresh water poured from the rivers during the summer, the climate of the 

 Bering Sea coast and Kotzebue Sound portions of this district is rendered much milder at this season 

 than it would be otherwise. The shallow water, its warmth, and the amount of sedimentary mat- 

 ter contained in it, render these portions of Bering Sea and the Arctic Ocean unfitted for the 

 swarms of small marine Crustacea and other animals which fill the water of the clear, cold, and 

 deep parts of the Arctic basins. This reacts upon the animal life, and various auks, fulmars, and 

 whales that abound in the deep cold water of the Siberian coast of Bering Sea, and thence north 

 in the Arctic Ocean, are rarely seen on the American coast of Bering Sea or Kotzebue Sound. 

 The portion of this district lying north of Bering Straits, excepting the country about the head ol 

 Kotzebue Sound, is essentially Arctic in all of its features. 



South of Bering Straits the coast country is more sub- Arctic in its general character, but to 

 the north the results of a rigorous Arctic climate appear in both plant and animal life. The surface 

 of the country in this part of the district is low and broken over much of its extent by rounded 

 hills rising into low mountains in parts. The immediate coast line is low and barren, broken in 

 places by bluffs and rocky promontories, the shingly beaches are backed in many places by lagoons, 

 the rolling tundra extending inland and covered with a layer of, moss and other Arctic vegetation. 

 From 50 to 100 miles inland, low, straggling belts of spruces commence to appear along the water- 

 courses. 



South of Cape Lisburne the summer climate is mild and rather pleasant, but north of this 

 raw, cold storms of rain, sleet, or fog are common. Along the coast of Bering Sea and Kotzebue 

 Sound the sea is free of ice from June until October, but north of this it is subject to being covered 

 at any time with drifting pack-ice, or it is open according to the force and direction of the pre- 

 vailing wind. In winter, however, open water is rarely found along shore. 



This entire district is underlaid by a layer of permanently frozen soil commencing near the 

 surface and becoming deeper the higher the latitude. At Saint Michaels a shaft 30 feet deep 

 failed to penetrate below this frozen soil. Over much of this district, except along the most ex- 

 posed parts of the northern coast, a plentiful Arctic vegetation is found, and about the coast of 

 Norton and Kotzebue Sounds grasses grow rankly — waist-high in places. Of course various mosses 

 and other cryptogamic plants common to Arctic latitudes are found in abundance everywhere. 



Saint Michaels, on the shore of Norton Sound, has a climate typical of this district, and below 

 I give the results of four years' observations taken by myself at that point. During the seven years 



