116 Cincinnati Society of Natural History 



The upper coarse-grained limestone horizon, associated with 

 Eridorthis, may be distinguished from the basal coarse-grained 

 layer most readily by the fact that Plcctambonites is very abundant 

 in the strata overlying the upper horizon while occurring only 

 sparingly above the basal layer. Moreover, the gasteropod hori- 

 zon, with Bellerophon rogerscnsis, Tetranota ohsoleta, Liospira 

 vitruvia, and the unknown Lophospira, occurs between the two 

 coarse-grained limestone horizons, not above the upper one. 

 Finally, Eridorthis is most common immediately above the basal, 

 coarse-grained limestone, but immediately below the upper coarse- 

 grained horizon. 



For a considerable distance north of the last described locality, 

 between 58.5 and 55.7, only the strata above the coarse-grained 

 limestone are exposed above railroad level. In these strata Plcct- 

 aiuhoiiitcs is abundant, and certain species appear which have not 

 been noted at lower levels. Among these are Diplograpfus {Meso- 

 graptus) piitilhis-eximius, and Trimidcus conccntricus. Strophom- 

 cna Jiallic and Hchertclla latasiilcata are much more common than 

 at lower levels. Ptcrinca dcniissa is seen occasionally. Pereno- 

 pora vera is abundant. Byssonychia vera is not rare. Ecteno- 

 crinus grandis^ CycJonema varicosnm-cincinnatiensis, Honnotoma 

 terchriforinis, Dahnanites cf. achates, and Proetus are rare. 



A mile and a half south of Sadieville, at 55.6 miles south of 

 Ludlow, a country road passes beneath the railroad. At the level 

 of the country road, the basal, coarse-grained limestone contains 

 H chert cUa, Platystrophia, and Cyclonema. The coarse-grained 

 limestone here is of considerable thickness, a vertical height of 18 

 feet being exposed above road level, Hebertella being present, even 

 at the top. Five and a half feet higher, gasteropods of the type 

 found in the gasteropod layer, between the two coarse-grained 

 limestone horizons, at locality 59.1, are common. Fossils in gen- 

 eral are not abundant until a level about 20 feet above the basal, 

 coarse-grained limestone is reached. The layers with Plcctambon- 

 ites common are not seen until a level 43 feet above the basal, 

 coarse-grained limestone is attained. Here it immediately over- 



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