362 The American Geologist. December, 1902. 
fieldella is characteristic of the Osgood formation. A slight 
unconformity is believed to exist between the Clinton and the 
Osgood formations, an intermingling of fossils occurring at 
the base of the Osgood. A greater thickness of the Osgood 
beds is seen at numerous points farther up the creek but no 
measurements were recorded. 
Near the mouth of Forbush creek, the Clinton is 14 feet 
thick, and is overlaid by the layer containing large crinoid 
beads and also the Whitfieldella. The Osgood is a foot and a 
half thick. The Whitfieldellas are common at a poor exposure 
near the home of William Richardson. 
Just below the mouth of Little Cub creek, the Clinton is 
16 feet thick. Crinoid beads and Whitfieldellas are very com- 
mon in the layer immediately above. The Osgood formation 
is 17 feet thick and is formed of the following beds in ascend- 
ing order : limestone, 3 feet 4 inches ; green clayey shale, 2 
feet 6 inches ; clayey limestone, 2 feet ; greenish clayey shale, 
about 9 feet. 
C. The southern extension of the Devonian along the 
ANTICLINE. 
The Devonian in the area occupied by the Cincinnati anti- 
cline consists of limestone overlaid by black slate. 
Devonian limestone. — At Louisville, the Devonian liiue- 
stone may be divided into two formations ; the lower or Jef- 
fersonville limestone, about 20 feet thick ; and the upper or 
Sellersburg bed, 15 feet thick. According to Edward M. Kin- 
dle,* the Jeffersonville limestone may be traced southward 
into Kentucky, but the Sellersburg bed has not been seen south 
of Louisville. The Sellersburg bed corresponds most nearly 
to the Hamilton of New York, while the Jeffersonville lime- 
stone is most nearly equivalent to the Corniferous or Onon- 
daga limestone. 
In Ohio, the Hamilton has been identified as far south as 
Delaware and Franklin counties. The Corniferous, however, 
may be traced farther south, to the western part of Pickaway 
county, t 
* E. M. KiNDLK. The Devonian and Lower Carboniferoii<i Favinas in 
southern Indiana and central Kentucky. Bulletin of American raleontology. 
No. 12, 1899. 
t Geol. Sur. of Ohio Rep. of r'rogress in 1870, pp. 285-286. 
