THE CINCINNATI GROUP 37 



base of the Richmond in Indiana, Ohio, and northeastern Ken- 

 tucky, and at some of the more northern localities they occur also 

 at the top of the Lorraine, but usually in much smaller numbers. 

 In fact, the base of the Richmond in Indiana and Ohio and north- 

 eastern Kentucky is usually indicated by the presence of several 

 thick layers of limestone, often wave-marked, and a first appear- 

 ance or sudden increase of Dalm.a7iella jugosa and of its related 

 form. 



A large form of Cyclonema bilix, having a vertical height of 

 fully one inch, is not rare. It appears most closely related to the 

 typical forms as illustrated by Ulrich.^ 



Helcionopsis striata is represented by a single specimen, show- 

 ing the characteristic markings on the surface. The specimen 

 is, however, only 14""™ long. The type specimen^ was found 

 in " the upper beds of the Cincinnati formation, Marion county, 

 Ky." Since the thickness of the Richmond formation in this 

 county does not exceed 35 feet, it is very probable that the type 

 specimen also came from the upper part of the Lorraine. 



Columyiaria stellata {^Colmnnaria alveolata as identified by Nich- 

 olson)3 is represented by a single specimen, showing alternately 

 larger and smaller septa, the larger extending nearly or quite 

 to the center of the visceral chamber. 



3. Richmond lime st07ie. — Immediately above the Warren bed, 

 at Clifton, there are nineteen feet of Richmond limestone. The 

 lower and middle part is coarse-grained, often cross-bedded, has 

 a lighter color, and contains very few fossils. The upper part 

 is more clayey and finer grained, forming a transition to the 

 Richmond shaly clays immediately above. The top of the 

 coarse-grained limestone and the clayey limestone above con- 

 tains a greater number of fossils, but these are usually imbedded 

 in the rock and cannot be secured without a considerable expendi- 

 ture of time. 



The identification of this limestone as Richmond is based 

 upon the presence of a single specimen of Rhynchotrotia capax 



"^ Minnesota Geol. Surv.,\o\. Ill, Part II, PL LXXVII, Fig. 35. 



'■ Ibid., p. 827. 



^Pal. Province of Ontario, 187S; also, Paleozoic Tabulate Corah, 1879. 



