GEOLOGY OF SOTJTHWESTEKN IOWA. 323 



No. 3. Black, fissile, carbonnceous shale, becoming clayey at top. 2% feet. 



No. 2. Compact limestone in two layers with marley parting \% feet. 



No. 1. Bluish, argillaceous shale, passing beneath the river bed. . 10 feet. 



Total 29 feet. 



No. 1, of this section is regarded as equivalent to No. 2, of 

 the section at Davis' mill, and although only a part of it is 

 exposed here, it is probably as thick as it is there. If this 

 identification of the strata is correct, FlG - 19 - 



none of the beds of the Terre Haute _-— -- -*"""*" 



section are so high in the series as the 

 highest of the section at Davis' mill are. 



At Mansfield's quarries on Short 

 creek, (section 29, township 70, range 

 26), a few small exposures occur, 

 and the accompanying section represented by Fig. 19, was 

 measured there. 



Section at Mansfield's Quarries. 



No. 5. Compact, gray limestone 3% feet. 



No. 4. Yellowish, calcareo-silirious shale 2 feet. 



No. 3. Yellowish, shaley limestone 3 feet. 



No. 2. Bluish, gray, compact limestone 2 feet. 



No. 1. Unexposed down to the level of the creek 4 feet. 



Total U% feet. 



At the point where this section was measured, "No. 5 is 

 quite compact, but the corresponding layers in the neighbor- 

 hood are usually not so. The stone of this bed is almost 

 everywhere largely made up of the Forameniferous shell 

 known under the uame of Fusulina cylindrica. 



Crossing over in a westerly direction to the valley of Grand 

 river again, we find a few exposures of the strata of the 

 Upper coal-measures. An exposure near Funk's mill reaches 

 almost sixteen feet in vertical thicknes of limestone with 

 marly partings. 



