Richmond Group in Ohio and Indiana. — Nickles. 207 
raine. Batostoma various (James), which also occurs abun- 
dantly in the Warren beds of the Lorraine, Bythopora mceki 
(James), which is very abundant, and Homotrypa dawsoni 
(Nicholson), a rather rare form, are among the most charac- 
teristic of the described species of Brvozoa. Some of the most 
characteristic Brvozoa are still undescribed. From the clay beds- 
a verv extensive pelecypod fauna has been obtained. To ob- 
tain these in abundance and in a good state of preservation 
special methods of collecting must be resorted to.* 
2. The Liberty or Strophomena planumbona beds. 
The strata of this subdivision consist of even-bedded lime- 
stones averaging three inches in thickness, prevailingly blue in 
color, with clayey and shaley layers intervening, which are also 
usually blue in color. Fossils seem to be less abundant in this 
division than in the one below and the one above. Especially 
is this true of the Brvozoa. In the Cincinnatian series the tre- 
postomatous Brvozoa are by far the predominant form of life, 
but in this subdivision the brachiopods appear to constitute a 
larger bulk of the strata than the Bryozoa. The thickness of 
this subdivision is about thirty-five feet. In a rough way this 
is the lower half of the Middle Richmond of my paper on "The 
Geology of Cincinnati." 
The first appearance of Hebertella insculpta (Hall) is con- 
sidered to mark the beginning of this formation. The H. in- 
sculpta has a limited vertical range, not over five feet and us- 
ually much less. It is very widely distributed. The writer has 
collected it at Madison, Versailles, and Roseburg in Indiana; 
at Dayton, Oxford, Oregonia and in Clinton county. Ohio. 
Above, these beds pass rather gradually into the next division 
on the west side of the uplift. On the east side a layer in 
which Streptelasma rusticumi (Billings) is very abundant 
marks about this horizon and may be considered the upper 
boundary. It has not come under observation whether or not 
there is such a layer on the west side also. 
* See paper by Henky Dickhaut. Collecting Fossils in the Cincinnati 
Shales, Ameiucan 'Geologist, xxiii, 1899, p. 335. 
t The writer doubts that the form from the Richmond of the Cincinnati 
area is specifically identical with the Streptelasma rusUoum of Billings from 
Canada. Indeed,' there seem to be three or four distinguishable forms in the 
Cincinnati which have been called by this name. The separation of these 
waits for the completion of the study of the collections made for stratigraph- 
ic purposes. The collections thus made, keeping horizons and localities 
carefully separate, have shown that a very large part of the paleontologlcal 
work which has been done heretofore on the fossils of the Cincinnati series 
is of a very loose character. 
