99 
MEDINAN, NIAGARAN; AND CHESTER FOSSILS 
In Pleurotomaria scutulata Lindstrom and P. gradata Lind- 
strom the median part of the slit-band is occupied not by a single 
striation but by two, a feature throwing these shells out of align- 
ment with Lophospira. In a similar manner the concave slit- 
bands of Clathrospira, Plethospira, and Seelya throw these genera 
out of alignment with Lophospira and its subdivision Ruede- 
mannia. 
Cyclonema daytonense Foerste 
Cyclonema bilix Foerste, Proc Boston Soc. Nat. Hist. 24, 1889, 
p. 290, pi. 5, fig. 15; Geol. Surv. Ohio, Pal., 7, 1893 p. 551, pi. 
30, hg. 15. 
Cyclonema daytonensis Foerste, 24th Ann. Rep. Indiana 
Geol. Nat. Hist. Surv., 1899, p. 77; Journ. Geol., 11, 1903, p. 707. 
Cf. Cyclonema bilix Comad, Jour. Acad. Nat. Sci. Philadel- 
phia, 8, 1842, p. 271, pi. 16, fig. 10. 
The type of Cyclonema daytonense is the specimen figured from 
Brown’s quarry, near New Carlisle, Ohio, in 1889, and again in 
1893, in the reports cited above. This species is widely dis- 
persed, and is one of the most common gasteropoda found in the 
Brassfield formation in Ohio, Indiana, and Kentucky. In the 
Brassfield limestone of western Tennessee it is found as far south 
as Clifton, on the Tennessee river, and it has been cited from 
Thebes, Illinois, and Edgewood, Missouri, from the Edgewood 
formation. 
The species C. bilix was described from Richmond, Indiana, 
where only the Elkhorn, Whitewater, and Liberty members of 
the Richmond, in descending order, are exposed. The Brass- 
field limestone is well exposed at the falls on Elkhorn creek, 3 
miles southeast of Richmond. 
The forms of Cyclonema found in the Whitewater and Liberty 
members are usually erect and relatively tall. Cyclonema bilix 
conica Miller^® is the extreme form of this group. It has been 
Miller, S. A., The position of the Cincinnati group in the geological column 
of fossiliferous rocks of North America: Cincinnati Quart. Jour. Sci., vol. 1, 1874, 
p. 320. 
