Jan., 1912.] The Arnheim Formation. 447 



also at Newsom, about 15 miles southwest of Nashville. At 

 Clifton, on the Tennessee river, about So miles southwest of Nash- 

 ville, Rhynchotrema dentata occurs associated with Dinorthis 

 carleyi, Leptaena riclimondensis, DalmaneUa jugosa var., and 

 Cohunnaria alveolata, at the Arnheim horizon. 



The connection of these Arnheim localities in Tennessee with 

 those in Kentucky is hidden at present by the covering of later 

 rocks. This connection probably extended from the vicinity 

 of Gallatin, in Tennessee, northward toward Bullitt county, in 

 Kentucky. It is significant that the most southern exposures in 

 Kentucky containing Dinorthis carleyi are in the northern part of 

 Nelson county, on the western side of the Cincinnati geanticline, 

 and in Mason county, on the eastern side. In the large series of 

 exposures of the Arnheim, connecting these localities across central 

 Kentucky, Dinorthis carleyi is unknown. Moreover, even Lep- 

 taena richmondensis and Rhynchotrema dentata disappear from the 

 Arnheim along the axial part of the Cincinnati geanticline and along 

 its eastern side long before reaching the Cumberland river in 

 southern Kentucky. 



11. Southern Kentucky along the Cumberland River. 



Richmond strata, containing Streptelasma, Stromatocerium, 

 and Cohunnaria, probably Coluninaria vacua, are exposed along 

 the Cumberland river, in the northern part of Wayne cotmty, 

 opposite the mouth of Forbush creek, and about a mile farther 

 west, below the mouth of Little Cub creek. This horizon probably 

 "Corresponds approximately to the base of the Liberty member of 

 the Richmond, as exposed in central Kentucky. Farther down 

 the river, the thin bedded strata, fonning the Waynesville member, 

 are exposed. Along the southern border of Russell county, at the 

 northern end of the first bend made by the Cumberland river on 

 reaching the county, a globular Prasopora and Heterospongia 

 -subramosa are present immediately above strata containing 

 Tlatystrophia ponderosa. Stratigraphically, this Prasopora here 

 occurs at the Arnheim horizon, but no diagnostic fossils were 

 found. The same horizon is exposed again at Harmon creek 

 shoals, about four miles farther down the river. 



No specimens of Prasopora have been seen at the exposures 

 below Creasy creek, below Indian creek, below Willis creek, or at 

 any of the other exposures farther down the Cumberland river, 

 in Kentucky, where strata equivalent to the Arnheim might be 

 expected to occur. 



12. Globular bryozoans in Casey and Lincoln Counties, Kentucky. 



At Kidd's store, in Casey county, about eight miles northeast 

 of Liberty, on the road to Huston ville, a globular bryozoan identi- 

 iied in the field as Prasopora, occurs at the Arnheim horizon, 



