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IOWA ACADEMY OF SCIENCE 
stone and fragments of shale. The npper portion grades upward into 
a distinct layer of dark oxidized material. Another eighty feet to the 
east the lower part of the reddish brown clay is found to. be the weath- 
ered top of the Des Moines shale; and, in one place above the clay, with 
no plane of separation, is four feet of a dark brownish laminated silty 
material containing an abundance of plant fibers. Apparently this 
upper deposit is continuous under talus with the upper part of the 
brownish deposit to the west. Throughout the remaining distance to 
the east end of the cut a bluish silty deposit two to three feet thick 
rests on the clay containing, fragments of plant fiber, with a two-inch 
plane of oxidation visible in places between them. Above this deposit 
to the soil is a bed of grayish loess which in places is very fossiliferous. 
Near the west end of the cut the loess is twelve to fifteen feet thick, 
distinctly laminated, and containing an abun dance of fossils. For per- 
haps four feet there is a four-inch plane of oxidation between the brown 
loess above and the gray below, but elsewhere no such plane is visible. 
The drift containing the two bowlders is unquestionably Kansan, 
though local evidence here is not fully conclusive. In tabular form 
these descriptions stand as follows : 
Feet. 
6. Soil, yellowish 1-2 
5. Loess, brown above where weathered, brownish where less 
weathered, gray where not weathered, distinctly laminated; 
with a few horizontal planes of marked* oxidation; and abun- 
dance of concretions and loess fossils.... 12-15 
4. Fine clayey deposit like silt, white where dry, bluish where damp 2 
3. Dark brownish laminated silty material, with abundance of plant 
fibers 4 
2. Clay, dense, with streaks of black and brown, with a fewjpebbles 
of quartz, chert and sandstone, and two bowlders (Kansan Drift.) 4 
1. Shale, mostly clayey, upper portion much weathered (Des Moines) 20 
Half a mile south of Avon a steam shovel is at work opening a gravel 
pit close to the one where years ago Mastodon or Elephant remains 
were reported found at a depth of about sixteen feet. For five feet 
from the surface the deposit is a dark sandy loam, very slightly lami- 
nated, and containing Kansan pebbles of all kinds scattered through it 
and lying in all possible positions. The pebbles are of all sizes up to 
a very few three inches' in diameter, the average of the largest being 
perhaps one inch. One rounded mass of sand (a sand bowlder or cobble) 
four inches in diameter contained a two-inch pebble in its lowest por- 
tion. At the bottom of the five feet the deposit is more distinctly a 
sand and gravel. 
