100 GEOLOGY OF OHIO. 
Until the commencement of the present survey it was supposed that 
the Lower Carboniferous limestone did not extend into Ohio, but that, 
rapidly thinning northward, in passing from central Kentucky to the 
Ohio river, the whole mass wedged out. The investigations of Prof. 
Andrews and his assistants in the south-eastern quarter of the State have 
shown, however, that the Lower Carboniferous limestone does reach into 
Ohio, and that it extends in a thin feather edge northward ore to the 
National Road. 
The best exposure of this limestone stratum—called by Prof. avarews 
the Maxville limestone—is in the vicinity of Newtonville, Muskingum 
county, where it is from fifteen to twenty feet thick. It is also visible 
in a layer of eight to ten feet in thickness in Scioto, Jackson, Vinton, 
Hocking, and Perry counties. 
In lithological character it is generally a gray, compact, partially 
crystalline rock, with few fossils, and these badly preserved. In certain 
localities, however, it contains considerable ferruginous coloring matter, 
by which it is striped and banded. In chemical composition it is a 
dolomite. Mr. Meek has examined the collection of fossils made from 
the Maxville limestone, and gives me the following memoranda upon 
them : 
LIST OF FOSSILS FROM THE MAXYVILLE LIMESTONE. 
1. Zaphrentis.—A small, undetermined, curved, conical species. 
Scaphiocrinus decadactylus, Hall ?—Described from the Chester group. 
3. Productus pileiformis, McChesney.—Described from the Chester group. Thought 
by Mr. Davidson to be the same as P. Cora, D’Orbigny. 
4. Productus elegans, N. and P.—Described from the Chester group. Some of the . 
specimens may be the form Prof. McChesney described from the same horizon 
under the name of P. fasciculatus. 
5. Chonetes.—Undetermined species. 
6. <Athyris subquadrata, Hall.—Described from the Chester (Kaskaskia) group. 
7. Athyris trinuclea, Hall, sp.—Described from the St. Louis (Warsaw) group. 
8 
2) 
SS 
Spirifer (Martinia) contructus, M. and W.—Described from the Chester group. 
Spirifer.— Undetermined fragments of perhaps two species. 
“10. Terebratula.—An undetermined, small, oval species, showing the fine punctures 
under a lens. 
11. Aviculopecten.—Undetermined species. 
12. Allorisma.—Undetermined fragments, apparently like A. antiqua, Swallow. De- 
scribed from the Chester group. 
13. Naticopsis.—A small, undetermined species. 
14. Straparollus perspectivus, Swallow, sp.—Probably a more elevated form of S. plani- 
dorsatus, M. and W. Both were described from the Chester group. 
15. Bellerophon sublaevis, Hall.—Described from the St. Louis (Warsaw) limestone. 
16. Pleurotomaria.—A small, undetermined cast. 
