The Rogers Gap Fauna of Central Kentucky 117 



lies the upper crinoidal limestone, whose exact thickness is not 

 exposed, although it is known to equal several feet. 



The upper coarse-grained limestone horizon is exposed also 

 at the cut south of 55.4. At the cut north of 55.4, Plectamhonites 

 becomes common eight feet above railroad level. At 55.3 the 

 upper coarse-grained limestone is overlaid by strata containing 

 Pcrciiopora vera, Strophomena hallie, and Trinucleus in strata 

 in which Plectamhonites is common. At 55.25, the upper, massive, 

 coarse-grained limestone is 8 feet thick, and is overlaid by strata 

 in which Plectamhonites is common. Several specimens of Eri- 

 dorthis and of Clitamhonites occur two feet above the base. At 

 55.1 the top of the upper coarse-grained limestone is down to 

 track level. At 55.0 the overlying strata contain Percnopora vera, 

 Hebertella latasulcata, Strophomena hallie, Byssonychia vera, and 

 Modiolopsis rogersensis, in addition to an abundance of Plectam- 

 honites. At 54.9 the upper coarse-grained limestone remains be- 

 low track level. At 54.8, the overlying strata, in addition to the 

 species alreadv named, contain also Trinuclens. 



In the cut extending from 54.7 to 54.6, Eridorthis occurs six 

 feet above track level, but is common only at the horizon between 

 one and two feet above the railroad, in strata which belong below 

 the horizon of the upper coarse-grained limestone. Cyclonema 

 varicosum-cincinnatiensis occurs at this upper Eridorthis hori- 

 zon. In the strata above the upper coarse-grained limestone Plect- 

 amhonites is common, and free cheeks of Acid as pis and a large 

 Lingnla occur. 



At the southern end of cut 54.3, the following species are found 

 between a level four feet above the track and the base of the cut : 

 Eridorthis rogersensis and nicklesi, Clitamhonites rogersensis, 

 Platystrophia colhiensis, Bellerophon rogersensis, and Modiolop- 

 sis rogersensis. Strophomena hallie, Strophomena higginsporten- 

 sis, and Clathrospira suhconica occur at the top of the cut, asso- 

 ciated with Ceratopsis chamhersi and occasional specimens of Eri- 

 dorthis. At 54.2 the top of the upper massive, coarse-grained 

 limestone is seven and a half feet above the railroad track, and 



13 



