Ulrich on Correlation of the Lower S'lnirian. iSr 
ilina^ but other fossils are rare. Near the bottom there is a 
massive subcrystalline layer, holding an abundance of Cyrfa- 
danta^ Tellinomya Bellerofhon troosti^ Safford, and JMurch- 
isonia gracilis Salter ( ?Hall). The fossils in this layer are sil- 
icified and well preserved. Near the top, again, there is often 
another layer in which the fossils are siliceous, and in which 
several of those found in lower layers reappear associated with 
fine examples of Tetradium Jibratum. 
Of the thirty or more species of fossils that have been col 
lected from these beds the following should be mentioned: 
Buthotrephisf succulens Hall. Bellerophon froosfi, Safford. 
Tetradium Jibrat inn Safford. Carinarofsis cunulac Hall. 
" tninorl' Safford. Pleurotomaria eugenia Billings. 
" columnare Hall. Alurchisonia biliciiicta Hall 
Stictopora paupera Ulrich. " gracilis Salter {} Hall). 
Zygospira recurvirostris Hall. " siaiiiicyoisis Safford. 
" ntodesta Saj, (seems to Tellinomya hartsvilletisis Safford. 
have modified from the preced- Cypricardites trcnio)icnsis n. sp. 
ing). Leperditia arinata Walcott. 
Hkynchonella increbescens Hall. " Josrphaiia ]one^. 
" procteri, n. sp. (Like [sochiliiia jom si Wetherby. 
R. dentata Hall, but narrower 
and with inuch more promi- 
nent and less incurved beak.) ' 
The beds designated as VIII, IX, X, probably constitute local 
divisions of a single series of strata. As, however, south of the 
Kentucky river in central Kentucky each is marked by its own 
lithological peculiarities as well as by a largely different fauna, 
it seems desirable to treat them separately. In tracing them to 
the north they decrease in thickness and seem to loose theii" 
identity, or one or two of the members run out. 
Thus, at Lexington, though still distinguishable, they are 
nevertheless more intimately connected and thinner than in 
Mercer and Boyle counties. At Cincinnati, as shown by deep 
well borings, they are represented by only twenty feet of ex- 
ceedingly tough, bluish-drab, limestone, indicating that the 
upper division is the most persistent. In northern Indiana they 
appear to be still further reduced, the hard cap of the Trenton 
being, according to the reports of the drillers, often less than 
five feet thick. 
Some beds exposed in the bank of the Ohio river at Point 
Pleasant, about twenty-one miles south east of the nn)uth of the 
Licking river opj-)osite Cincinnati O., arc referred to tliis horizon. 
