394 The American Geologist. June, 1904. 
from the next adjacent. There are also iron stained layers, c'zy beds 
and sandy beds, just as the loess shows, all proving aqueous agency. 
On every trip on the Missouri, whenever the boat would tie up, I 
would step ashore and notice, the structure of the river bank and the 
contents of the wreck heaps. On every wreck heap I would find 
among the trash hundreds of land shells, mostly Helices, and some- 
times the small Pupa all being land shells, and rarely did I find a 
Planorbis or Lymnea. The Succinta I would also find. These shells 
are also found with the loess. These in the river were washed down 
from the hills by the rains, and the shells in the loess came the same 
way. It IS very rarely that the loess is found more than six miles from 
the Missouri river, and on the south side not often a mile. In St. 
Louis county it is spread out over ten miles because the plain is not so 
high above the river. 
At two places in southern Missouri I have seen what appears like 
glacial drift, viz: at Big Salt Spring, Saline county, fifteen mi^es from 
Missouri river, and in St. Louis county at the head of Hamiltcn creek 
there are pebbles on top of a hill probably 250 feet above the Missouri. 
The velocity of the Missouri varies from two to three miles per hour 
at low water to ten at high water, the slope about 0.88 feet per mile 
for high and low water. 
Estimates made by Colonel Suter at St. Charles show that for one 
year the amount of sediment carried past would amount to one square 
mile 197 feet deep. 
The depth of the valley between the hills to the rocks below is 
from 70 to 100 feet and 40 to 80 feet below the bed of the river : at St 
Joseph about 40 and at St. Charles nearly 100. 
The width of the valley between bluffs is about the same from St. 
Charles to Boonville about 2^ miles ; at Waverly it is 5 miles, at Sib- 
ley 41^, at Kansas City 2^, at Leavenworth 4, at St. Joseph 4, at Rulo 
9, at Omaha 5, at Sioux City 8. G. c. broadhead. 
Columbia Mo., April 2, 1904. 
Proposed examination of the arid belts of South Africa and 
South America. In thinking over your highly suggestive and almost 
convincing paper on the causes of .he Glacial epoch, it strikes me that 
in view of the difficult conservation of the evidences of glacial action 
and of glacial deposits in the tropics with their excessive rainfall, it 
would be of special interest, and at least next-best, to have the adja- 
cent arid belts studied with respect to former glaciation. It is true that 
even there, glacial scorings would hardly be preserved, because of the 
destructive effect of the extreme changes of temperature prevailing 
there, which cause even cobbles to explode so frequently. But all 
other evidences of past glaciation, such as boulders, moraine^ drum- 
lins et id onine, should be particularly well preserved on acount of 
the absence of the erosive action of heavy rainfall. We have but very 
few observations on the details of surface conformation in the arid 
belts, except in respect to aeolian 'ffects. Svcn Hedin had a good op- 
