Jan., 1914.] Richmond Beds of the Cincinnati Group. 233 



Sometimes 2'-3' below this second Tetradium reef is another 

 V of Tetradium. Between these Indian Creek exposures and 

 Oxford this reef disappears and is not known to the east. 



And between the two reefs at this locahty are not only the 10' 

 of Bryozoa beds, but about 20' of characteristic soft, lumpy, 

 shaly Whitewater strata with the characteristic Whitewater 

 fauna. The Rhynchotrema dentata beds appear just above the 

 reef. Hence we see from the position of these tw^o reefs that the 

 Saluda is in part the equivalent of the Whitewater. 



Returning to the Madison section to pick up another marker 

 and trace it through, we find that the extreme to]3 of the Richmond 

 is again fossiliferous. Just above the Hanging Rock these fos- 

 siliferous strata begin with S" of thin limestones and dark shale, 

 with Byssonychia richmondensis, Pterinea demissa, Orthoceras 

 hammelli, Labechia ohioensis, and Tetradium minus. Next is 

 a 16" massive dark limestone, with a richly fossiliferous film of 

 rather poorly preserved fossils on the top. These fossils constitute 

 a distinct and peculiar fauna, part of which appears to have no 

 near relationship in the Cincinnati. The more common species 

 are Labechia montifera, Labechia sp., Streptelasma sp., Cteno- 

 donta sp., Pterinea demissa, Liospira sp., Holopea hubbardi, 

 Lophospira hammelli, Orthoceras hitzi, O. gorbeyi, and Cyrtocer- 

 ina madisonensis. At the exposures along the road to Hanover, 

 three miles west of Madison, there are added Hebertella sinuata, 

 Platystrophia acutilirata, Leperditia caecigena, Labechia ohioensis 

 and Tetradium mintis, there being no distinction here between 

 the two fossil layers as at Madison. This assemblage of fossils 

 constitutes the so-called "Hitz fauna." 



Between the Hitz fauna proper at Madison and the Ordovician- 

 Silurian contact, is a 2' 4" limestone with all of the ostracods listed 

 from the vSaluda of Oxford, except Leperditia appressa, and with 

 Entomis madisonensis added. This ostracod limestone is not 

 distinct at the locality three miles west. 



Between Madison and Cooper's Falls the Tetradium and Labe- 

 chia become consolidated into a rather definite reef, though not 

 of great thickness. At Cooper's Falls this reef is 13^' thick. It 

 is about 19' above the second Tetradium reef and 5' beneath the 

 Silurian contact. These 5' are massive limestones much like the 

 top limestones at Madison, and carry a reduced Hitz fauna. The 

 Hitz fauna is seen no farther toward the north. 



This third reef is seen constantly at about this level, whereever 

 it is exposed, around the northern edge of the Cincinnati outcrops 

 as far east as the vicinity of Waynesville, O. The only place 

 where it was not seen was at Laurel, and a more careful examina- 

 tion of the strata would doubtless show it here. 



On Elkhorn Creek the total thickness of the beds between the 

 level of the lower reef and the Silurian contact is about 125', as 



