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IOWA ACADEMY OF SCIENCES. 
D. A brush-covered hill just above the exposure marked E. 
Altitude about 170 feet. A small collection contain- 
ing species 11 and 30 was made. 
E. A locality in the northwestern part of Pairmount park, 
on a northerly slope, somewhat grassy, but with 
shrubs and a few Bur-oaks, nearly opposite Eighth 
avenue. Altitude 280 to 300 feet above the valley. 
Here we found species 3, 8, 11, 13, 18, 19 and 27, and 
also one specimen of Bifidaria procera, the only recent 
species found in the tract examined, which was not 
found in the loess. This locality is just over the 
brow, on the north or leeward side* of one of the 
most exposed ridges in the area under consideration. 
F. A part of the same slope immediately below E, and 
fifty to 100 feet lower. Here the forest is better 
developed and contains a number of species of trees. 
Species 8, 11, 18, 19, 22, 25 and 28 were found. 
The points E and F are on the same very steep 
slope, but E is much more exposed and drier, P being 
more protected by its forest covering and position. 
A comparison of the species' from these points is 
therefore interesting. Species 3 and 13, while com- 
mon at E were not found at F the lower point. While 
18 was common at E, only one specimen was found 
at F. Number 19 is also more common at E than at 
F. These facts are of interest when we seek to 
determine the extent to which shells are likely to be 
washed down even very steep slopes. Numbers 8 
and 11 were about equally abundant, while numbers 
22, 25 and 28 were found only at F. 
G. The banks and grassy slope near and above the expos- 
ure M. This yielded species 3, 13, 21, 24 and 27. 
It will be observed that species 1, 3, 4, 5, 6, 7, 9, 12, 14, 15, 
16, 17, 20, 23 and 26, — or just one-half the total number, — are 
not contained in the collections of modern shells cited. The 
number of individuals of the surface species is also compara- 
tively small. Of these numbers, 1, 16 and 23 are extinct in that 
section of the country, number 1 occurring eastward, number 
16 westward, and number 23 being entirely extinct. 
The modern fauna of the more or less exposed hills at Coun- 
cil Bluffs is much poorer in species and in specimens than the 
*The prevailing- winds during- the seasons of the year when the snails are active, 
are from the southwest. 
