210 
A ug. F . Foerste 
In this classification the term Nicholas is used to designate the 
more coarse grained limestone section at the top of the Cynthiana 
formation. Southwest of Pleasant Valley, in Nicholas countv, 
Ky., this limestone section is typically developed and has a thick- 
ness of 35 feet. Northward, along the Ohio river, its thickness 
decreases. The term Point Pleasant should be restricted to the 
lower part of the exposures at Point Pleasant, as intended by 
Professor Orton. That part of the river quarry beds at Cincin- 
nati which contains Trinucleus concentricus does not belong to the 
Point Pleasant part of the Cynthiana formation. Formerly, when 
these beds were studied by Professor Orton, the lower part of the 
section at Point Pleasant was well exposed, considerable quarry- 
ing was carried on, and the rock from these lower layers was sent 
in large quantities to Cincinnati. At present, scarcely a trace 
of these quarries can be found. 
The Fulton layer is the Tnarthrus becki horizon, about 5 feet 
thick. The Eden was described by Orton, but formerly included 
also the Mount Hope beds, now referred to the Maysville. The 
Maysville includes the strata assigned by Orton to the Hill quarry 
beds. The Richmond corresponds to the Lebanon beds of Orton. 
Protarea richmondensis, nom. nov.. 
Corallum incrusting, forming a layer usually about 2 milli- 
meters in thickness, Put sometimes equalling 3 or 4 millimeters; 
with about 4 corallites in a width of 5 millimeters. There are 
twelve septae, with distinctly denticulate inner margins, which 
reach scarcely to one-half of the distance from the walls to the 
center of the calyces. At the base of the calyces the denticles or 
granules are arranged rather irregularly. In the specimen selected 
as a type the calyces are rather deep and the septae distinct. In 
numerous other specimens, represented by figs. 9 5 , on plate i, 
the incrustation is thinner, the calyces are more shallow, the sep- 
tae are not so clearly defined except near the margin of the calyx, 
and the granules scattered over the base of the calyx are larger and 
more conspicuous. In none of the specimens have any clearly 
defined vertical tubules been found between the walls of the coral- 
lites. 
Protarea richmondensis is common in the Whitewater beds, at 
Dayton, Ohio, where the type specimens were obtained, and it is 
