242 Geology and Botany of Northern Pacific Railroad. 



XL — Notes on the Geology and Botany of the Country bordering 

 the Northern Pacific Railroad. 



BY J. S. DEWBERRY. 

 Read February 4th, 1884. 



Having been several times over the line of the Northern 

 Pacific E. K., and through the country bordering the lower 

 Columbia and Puget's Sound, and having found some things 

 that were of interest to me, I venture to offer a few notes upon 

 them to the members of the Academy. 



Going west from Duluth to Brainerd, the line of the road for 

 the most part lies in what is evidently the old deserted bed of a 

 westward extension of Lake Superior. The ground is still low 

 and swampy, and much of the surface is formed of what is un- 

 mistakably lake sand. 



From Chicago through Wisconsin and Minnesota, the road 

 passes over an almost unbroken sheet of drift, which though of 

 great interest, has been so fully illustrated in the able reports of 

 Messrs. Chamberlin, Winchell and Upham, that nothing further 

 need be said here in regard to it. At various points the true 

 till is seen, with its striated pebbles; and one such exposure is 

 within reach of every traveler, at Audubon. Beyond this, the 

 boulders are scattered over the surface, and pebbles in the 

 ditches continue as evidence of the transport of material from 

 the eastern highlands. About Bismarck the boulders, though 

 fewer, are still not rare, and are gathered in groups, as elsewhere 

 along the margin of the drift area, constituting a kind of fringe, 

 and suggesting their transport by ice floats. The last of these 

 boulders is seen at Sims, about 20 miles from Bismarck. From 

 this point to the crossing of the Little Missouri, one could hardly 

 find a stone to throw at a bird, or a shrub big enough to make 

 a tooth-pick. This region is an extension northward of that 

 broader prairie area which I have crossed in many places further 



