Lansing Pleistocene Geology. — Winchell. 305 
coarser grains, the sandy element is found to consist chiefly 
of debris from limestone, fragments of fossils, small crinoid 
stem joints, and rounded white quartz grains. There are also 
some small rusty sandstone fragments, and fragments of sandy 
shale. The coloring element is bog ore. 
No. 7 cannot be distinguished microscopically from No. i. 
No. 8 is like No. 6, but the iron is more evenly 'distrib- 
uted, producing a general rustiness rather thar bog ore. Some 
of the quartzes are purplish, as if from the Potsdam quartzyte 
of South Dakota, indicating a derivation since the Kansan 
drift was spread. One microscopic cinnamon-garnet was 
noted in the washed sand. 
No. 10. Carboniferous shale. Microscopically this is iden- 
tical with No. I, and with No. 4a, and shows the source of 
those members. 
Inferences front the microscopic characters. 
It is evident from the foregoing that there is not a uni- 
formity in the characters of the substance lying on the lime- 
rock floor. The same is apparent from the descriptions of the 
stations above. At the entrance the limerock is first covered 
by a stony debris (la) mixed with loess, both resulting doubt- 
less from recent dislodgment from above. At sixteen feet from 
the entrance this is replaced by a rusty sandy stratum about 
eight inches thick (ic) made up of angular limestone sand, 
corroded residue of fossils from the Cai^boniferous, rounded 
quartz grains and small bits of rusty shaly sandrock containing 
also much rounded and rusted and corroded small masses of 
limestone. This continues beyond thirty-five feet but is ap- 
parently wanting at fifty feet from the entrance and does not 
certainly reappear at seventy-two feet. This is evidently a 
waterlaid substance, the assorting action having been sufficient 
to carry away the most of the clayey ingredient had it been 
present. The bog ore which in part characterizes its upper 
portion indicates surface exposure, but not necessarily a condi- 
tion of humus. At fifty feet the first substance over the rock 
floor seems to be of the nature of No. 2 (loess) but probably 
with a large ingredient from No. i. At eighty-three feet from 
the entrance the limerock passes under Carboniferous shale 
ill situ. The composition of No. ic denotes post-Kansan or- 
igin. The presence in No. ic of considerable rusty sandstone, 
