Black Shale is seen in the road side and in a field to the south. It rests on densely crinoidal, dark grey Corniferous rock. The lower part of the Corniferous is finegrained and con- tains few crinoidal re- maines. The total thick- ess of the Corniferous is about 6 1/2 feet. Imme- diately below the Cornif- erous & Columnaria alt. reolata, and 2 feet below, the regular Madison beds are exposed. Following the road down hill, the total thickness of the Madison is seen to be about 20 feet thick, possi- bly more. 1100 Chicago R.R. level. 1100 taken as a reference point. 113 113 About a quarter of a mile south of Chicago, a road branches off from the Ren- wick's wide road and goes toward St Marys. About 3/4 of a mile away this road, the Black Shale is seen to rest directly on the Clinton. This is still better seen in a small stream bed west of the road. The first widely pos- siliferous Clinton bed, where normally is seen 5 feet below, the top of the Clinton, is here seen about 2 or 3 miles be- low the Black Shale. The Clinton is about 11 feet thick. The upper half is full of chest lenses and nodules. On the lower half occurs a massive dark limestone near by without chest, which is not at all typical for the Clinton. Its fossils are the same here- ever. Below the Clinton are the Madison beds. The following fossils were observed: See next page. 81