i8 



Aug. F. Foerste 



The following classification of Cincinnatian and Lexington 

 strata is here adopted : 



Series 



Formations 



Cincinnatian. 



Richmond. 



Beds 



Elkhorn 



Whitewater 



Saluda 



Liberty 



Waynesville 



Blanchester division 

 Clarksville division 

 Fort Ancient division 



Arnheim 



Oregonia division 

 Sunset division 



Maysville. 



Eden 



Utica 



Cynthiana. 



Upper Mohawkian .[ Lexington 



I 

 I. 



f Mount Auburn 

 I Corryville 

 •{ Bellevue 

 I Fairmount 

 I Mount Hope 



McMicken or Paint Lick 



Southgate 



Economy 



Fulton 



{ Nicholas 

 ■^ Greendale 

 / Perryville 



( Paris 



) Wilmore 



] Logan a 



I, Curdsville 



The Arnheim bed has been separated into two divisions, the 

 upper or Oregonia division, exposed in the Blacksmith hollow, 

 northeast of the railroad station at Oregonia, Ohio, being character- 

 ized by the introduction, at the base, of the characteristic Richmond 

 fossils : Leptacna ricJiiiiondensis-prccursor, Rhyncliotrcina dcntata- 

 arnhciniensis, and Dinorthis carlcyi. On the eastern side of the 

 Cincinnati geanticline, the lower half of the Arnheim is much less 

 fossiliferous, and is terminated by a layer containing Platystrophia 

 ponderosa. Southward, in Kentucky, this horizon consists of com- 

 paratively unfossiliferous argillaceous limestones, containing com- 

 paratively few specimens of this Platystrophia. A typical exposure 

 is found about half a mile southwest of Sunset, along the road to 

 Day's Mill, and from this locality the term Sunset division has 



