8 NORTH AMERICAN FAUNA. [no. 19. 



rent we were :i))le to make easy and rapid progress. Thus we con- 

 tinued until an unfortunate capsize between Fort Yukon and Fort 

 Hamlin prevented further detailed work on the river, and we were 

 obliged to proceed direct to St. Michael, where a month was spent in 

 collecting on the coast and tundra. Finally, late in September, our 

 work was brought to a close ])y the approach of the long arctic winter. 

 We returned to Seattle on the U. S. revenue cutter Cortrhi^ which 

 stopped on her way for a few hours art St. George Island and at 

 Unalaska, at each of which places we collected a few l)irds. 



A relatively large part of our time was spent in the White Pass 

 region and about the headwaters of the Yukon, as this was an ahso- 

 lutel}^ virgin lield, whereas part of the lower river had })een previously 

 visited l)v naturalists. We were unable to do any collecting in the 

 mountains which lie back from the river, owing to the great distance 

 to be covered and the shortness of the season. Legions of mosquitoes 

 were attendant upon us almost constantly. At first they seemed posi- 

 tivel}' unbearable and were a real hindrance to the work, but we grad- 

 ually became accustomed to them, and Mj the use of gloves, head nets, 

 and canopies to sleep under, managed to exist in comparative comfort. 

 Aside from insect pests, however, outdoor life on the Yukon in June 

 and Jul}' is very enjoyable; good camping places are abundant, and 

 the weather is mild and beautiful. During the latter part of August 

 and in September strong winds sweep up the river and frequent rains 

 occur. 



FAUN AT. DISTRICTS. 



The country traversed mav l>e divided for convenience into five dis- 

 tricts: (1) The Lynn Canal district, (2) the White Pass district, (3) 

 the Canadian Yukon district, (i) the Hudsonian Yukon district, and 

 (5) the Alaska Tundra district. These districts are limited in a 

 general way by their respective life zones, but they^ are not of equal 

 extent or importance, and the names applied to them are used not to 

 specially designate restricted parts of zones alread}' recognized, but 

 purel}^ as a matter of convenience. They are longitudinal districts — 

 that is, they are very much longer than wide, and each is merely a nar- 

 row tract covered by our route through some larger fauna! region. 



Lynn Ccmul dlst/'ict. — Skagway and the country bordering Lynn 

 Canal are in the northern part of that faunal area which Nelson has 

 called the 'Sitkan district' and which has often been included in the 

 Northwest Coast district. The trees and shrubs are much the same as 

 those at Juneau, Wrangell, and other points farther south, but the vege- 

 tation is not quite so dense and luxuriant. The shores of Lynn Canal 

 are steep, rocky, and comparatively sparsely timbered, but in some 

 places, as at Haines, low, swampy ground and heavy saturated forests 

 are found. At Skagway, poplars {Populus treviulmdes and Pojndus 



