389 



Correlation of the Outcrop at Spades, Indiana. 



H. N. Coryell. 



Introduction. 



The collections forming the basis for the present paper were care- 

 fully made by the Rev. T. A. Bendrat, M. S., during the autumn of 1913, 

 from the exposure one mile west of Spades, Indiana. His careful descrip- 

 tion of the outcrop has been of considerable value in the correlation. 



The identifications of the species were made in the laboratories of the 

 Department of Geology of Indiana University under the supervision and 

 direction of Professor E. R. Cumings and Dr. J. J. Galloway. Their 

 assistance and suggestions have been of great value. 



The Present Divisions of the Richmond. 

 Richmond — 



Elkhorn ( Platystrophia moritura zone). 

 Whitewater (Homotrypa wortheni zone). 

 Saluda (Tetradium minus zone). 

 Liberty ( Strophomena planumbona zone). 

 Waynesville (Dalmanella meeki zone). 



Description and Stratigraphy. 



The reconstruction of the Cincinnati Division of the C, C, C. & St. 

 L. Railroad through Ripley County, Indiana, iu 1902-04 made available 

 for study a section of strata high in the Cincinnatian one mile west of 

 Spades. The exposure at present is from five to six feet high and in 

 places partially covered with debris, leaving, however, distinct ledges out- 

 cropping. The strata are approximately horizontal. The limestone at the 

 base of the exposure weathers to a bluish-gray ; it is very variable in 

 texture, some portions being very finely crystalline, others containing quite 

 large calcite crystals, as well as geode formations and iron concretions. 

 Above this limestone the strata become more argillaceous, thinly bedded 

 and present a distinct shaly structure. 



