STRATIGRAPHY OF FOSSILIFEROUS MEMBERS 61 



A small collection was made from loose blocks of limestone which 

 had fallen from place in the walls of a small ravine by the side of the road 

 just east of the Muskingum River and opposite Rock Cut (Locality 40). 



Crinoid segments very abundant 



Derby a crassa (Meek and Hayden) 



Chonetes mesolobus Norwood and Pratten 



Productus cora d'Orbigny 



Productus semireticulatus (Martin) 



Pustula nebraskensis (Owen) 



Marginifera wabashensis (Norwood and Pratten) 



Composita subtilita (Hall) 



About one-fourth mile north of Locality 40, an excellent outcrop 

 occurs in the bed of a small stream flowing from the east into the Mus- 

 kingum River, which affords one of the best collecting places for Lower 

 Mercer fossils which was found. The stream forms a small waterfall 

 over hard limestone, about 1 foot thick, above and below which 

 occurs soft, black, extremely fossiliferous shale. These shales are com- 

 posed of a mass of crushed and macerated animal remains among which 

 a few species of brachiopods and crinoid stems predominate. Col- 

 lections were made from both the limestone and shales (Locality 41). 



FOSSILS FROM THE BLACK CARBONACEOUS SHALE BELOW THE LIMESTONE 



Plantae abundant 

 Crinoid segments 



Orbiculoidea meekana (Whitfield) 



Derbya crassa (Meek and Hayden) 



Chonetes mesolobus Norwood and Pratten 



Productus cora d'Orbigny 



Productus semireticulatus (Martin) 



Pustula nebraskensis (Owen) 



Marginifera muricata va,r. missouriensis Girty 



Marginifera wabashensis (Norwood and Pratten) 



Spiriferina kentuckyensis (Shumard) 



Spirifer boonensis Swallow? 



Composita subtilita (Hall) 



Aviculopecten coxanus Meek and Worthen 

 Acanthopecten carboniferous (Stevens) 

 Entolium aviculatus (Swallow) 

 Astartella varica McChesney 



FOSSILS FROM THE LOWER MERCER LIMESTONE 



Crinoid segments 



Septopora biserialis (Swallow) 



Derbya crassa (Meek and Hayden) 



