98 
IOWA ACADEMY OP SCIENCES. 
the temperature must have been close to 20 degrees F. 
Apparently tender vegetation — beautiful wild flowers — seem 
to laugh at these little touches of winter, and likewise, in the 
Hot Springs where the water boiled eggs in twenty minutes, 
at least one alga grows in considerable abundance. 
THE DISTRIBUTION OF LOESS FOSSILS. 
BY B. SHIMEK. 
It has perhaps been noted that the loess molluscs thus 
far reported in the literature of the subject are, for the 
most part, from localities in close proximity to larger streams. 
This fact may have suggested the thought to those unfamiliar 
with the modern habits and present distribution of these 
molluscs that the adjacent streams had in some way something 
to do with the entombing of the shells now found in the loess. 
That the loess is most richly fossiliferous near streams is 
generally, though not always, true. The abundance of fossils 
is a decidedly variable quantity. There are exposures near 
streams which exhibit fossils in profusion, and others which are 
wholly barren. On the other hand, exposures quite remote 
from streams contain fossils, — though in such situations a 
proportionately much larger part of the loess is entirely devoid 
of them. 
This fact has sometimes led geologists to attempt to dis- 
tinguish, in varying degrees, between the loess adjacent 
to streams and loess more remote. Whatsoever distinction 
may be observed in the physical character of the loess of var- 
ious deposits,* no distinction can be based on the presence 
or absence of fossils alone. The simple fact that one deposit is 
fossiliferous and another is not, does not prove, nor even 
indicate, that the deposits were formed under wholly, or even 
materially, different circumstances. In the one case there are 
no fossils, simply because there were no shells to be buried; in 
the other, fossils are common because shells were abundant on 
the old land surfaces, where they were covered as other 
imperishable objects would have been covered. 
*For one of the most recent discussions of the loess, with reference to its variation 
according- to distance from streams, see Doctor Chamberlin’s article in the Journal of 
Geology, Vol. V, No. 8, p. 795. 
