Helicotoma brocki Foerste. 



Ascoceras sp. 



Spyroceras hammelli Foerste. 



In addition to these there are many gastropods 

 and pelecypods not as yet identified. 



These fossils suggest the upper Waynesville division 

 of the Richmond formation as exposed in Ohio, Indiana, 

 and Kentucky. The following species occur not only 

 below the Stromatocerium horizon, but range also into 

 the strata above — 



Strephochetus richmondensis Miller. 

 Stromatocerium huronense Billings. 

 Calapoecia huronensis Billings. 

 Columnaria alveolata Goldfuss. 

 Streptelasma rusticum Billings. 

 Tetradium huronensis Foord. 

 Hebertells occidentalis Hall. 

 Rhynchotrema perlamellosum {Whitfield) . 

 Zygospira kentuckiensis James. 

 Zygospira modesta Hall. 

 Pterinea demissa {Conrad). 



All these are spec'es which can exist under very 

 adverse condit ; ons in fairly muddy water. 



Middle Richmond. — -The thirty feet of strata which 

 overlies the Stromatocerium reef at the Clay Cliffs belong 

 to the lower part of the Middle Richomnd. Here, 

 occasional specimens of Beatricea undulata, and rather 

 numerous specimens of Liospira helena, and of various 

 thick-shelled species of Bucania and Bellerophon occur. 



The Beatricea undulata horizon is exposed also in 

 the gully a short distance north of the light house at Manit- 

 waning. Here, the Cape Smyth Stromatocerium reef is 

 absent, and the corresponding horizon is approximately 

 indicated by strata in which Columnaria alveolata and 

 Calapoecia huronensis are fairly abundant. Eastward, 

 this horizon is represented by the Gore Bay Columnaria 

 reef. Three and a half miles south of Little Current, 

 Strophomena vetusta and Ceraurus ( Eccoptochile ) meeka- 

 nus, Miller, occur immediately above this Columnaria 

 reef, and suggest a trace of the Liberty fauna of Ohio 

 and Indiana, while the Beatricea undulata, the abundance 



35066—6 



