2 University of Michigan 



again ascended in August to Kaltshak, from near which a portage 

 was made to Russian Mission-on-the- Yukon. Here, in September, 

 a river steamer was boarded, and from St. Michael passage was 

 secured to Seattle. 



The part of Alaska for which the land vertebrate associations 

 are here described includes the interior of the territory north of the 

 Alaska Range, south of the Endicott Mountains, and east of the 

 Bering Sea tundra. This area is the Alaskan-Canadian faunal 

 district of Nelson,^ and is part of the Hudsonian Yukon district 

 of Osgood.^ The timbered parts would be considered in the 

 Hudsonian life-zone, while the areas above timber-line are in the 

 Arctic-alpine life-zone. 



The land vertebrate associations of interior Alaska may be 

 listed as follows: 



Aquatic Black spruce 



Shore Timber-line willow-alder 



Cut-bank Blueberry-dwarf birch 



Cliff Bare-ridge 



Equisetum " Rocky-slope 



Sedge Aerial « 



Niggerhead Burn 



Valley willow-alder Cultivated-field 



Poplar Edificarian 



White spruce-paper birch 



The descriptions of the habitats and associations here given 

 are based mainly on the study of the regions near Fairbanks, near 

 Tanana, and along the Kuskokwim River. A brief preliminary 

 description of the region has already been given. ^ 



' E. W. Nelson, Report upon Natural History Collections Made in Alaska, 

 1887, p. 32. 



^ W. H. Osgood, North American Fauna, Xo. 19, 1900, 13-15. 



3H. J. Christoffers and L. R. Dice, U.S. Bur. Fish. Doc, Xo. 780, 191 2, 



lOO-III. 



