Richniond Group of Cincinnati Anticline— Focrstc. 337 
above this level. The lower part, a foot and a half thick, is 
more connected; the upper part, three and a half feet thick, 
consists of nodular limestone masses more or less separated bv 
clay. This forms the top of the Warren bed. Five feet above 
this level DahnancUa jngosa occurs in a very clayey limestone. 
A layer of hard limestone containing great numbers of this 
fossil is found seven feet higher up. The upper range of this 
fossil is not well exposed here. 
Two miles south of Oregonia, on the main road from Leb- 
anon to Wilmington, Dinorthis retrorsa occurs ninety-one feet 
above the level of the railroad, at a little stone culvert, just 
north of the bend where the road ascending the hill turns 
sharply eastward. The top of the Warren bed is twenty-one 
feet farther up, and five feet higher DahnancUa jngosa occurs 
in a clayey nodular limestone. It is much more abundant in 
the clays and thinbedded limestones immediately above, and 
has a range of at least fifty feet. At this locality the lowest 
specimens of Strophomena rugosa were found in the upper 
part of the Dalmanella jngosa zone. 
Along its northern line of outcrop in Ohio and Indiana, the 
lower part of the Lower Richmond is characterized -by the 
great abundance of DahnancUa jngosa. While at several lo- 
calities this species appears to occur in small numbers in the 
upper, nodular part of the A\'arren bed, its increase in the low- 
er part of the Lower Richmond is so abrupt that it is one of the 
most useful fossils for determining the line between the War- 
ren and the Lower Richmond. Southward the Dalmanella 
jugosa zone thins out. While ver}- abundant at Concord, Ken- 
tucky, no traces of this fossil were seen at Owingsville or near 
Spencer. On the western side of the Cincinnati anticlin-:. it 
has not been seen south of Alarble Hill in Indiana. 
The mo§t southern outcrop of Dinorthis retrorsa on the 
eastern side of the Cincinnati anticline is at Arnhelm. in 
Brown county, thirteen miles north of the Ohio river. Dal- 
maneUa jugosa and HeherfeUa ins c nipt a are common at Con- 
cord, Kentucky. Cata.'syga Jicadi occurs ten miles south of 
Maysville, Kentucky. 
Protarea vetusta, Strcptelasma rnsticum (Str. cornicnhini 
of the Ohio survey), Strophomena sulcata, and Rhynchotreina 
capax range from the lower part of the Lower Richmond to 
