78 Cincinnati Society of Natural History. 
imperceptible difference, 14:mm., in the diameter of the two extremities. 
Although the specimens are in an elegant state of preservation, so far 
as the outside marking is concerned, they are silicified, and no evidences 
of the siphuncle remain. | 
Remarks.—As this is the second species of this remarkable genus, 
considerable interest attaches to its discovery. It occurs with the 
species of Amygdalocystites, Hybocystites, Comarocystites, Apiocy- 
stites (?), Porocrinus, Hybocrinus, Paleocrinus, Blastoidocrinus, 
Carabocrinus, Hdrioaster (?), etc., which I have discovered in the 
Trenton rocks of Mercer county, Kentucky. 
I have found four specimens, one of which is three times the dimen- 
- sions of the type herewith figured, and is, no doubt, a different species. 
I dedicate this rare fossil to my friend, Robert Clarke, Esq., who has 
assisted me in my labors by the generous donation of his large col- 
lection of shells, minerals, and fossils, to the University Museum, and 
also by the use of rare books from his extensive paleontological 
library, as well as by the warm interest he has always taken in my 
studies. 
Cyrrtoceras Goldfuss, 1832. — 
CYRTOCERAS CONOIDALE, ‘nov. sp. (Plate IL, figs. 6, 6a.) 
Shell very rapidly tapering, consisting of numerous short septa, of 
equallength. The specimens which I regard as typical, fig. 6a, Pl. IL, 
have a comparatively slight curvature. There are seventeen septa in a 
length of one inch. The siphuncle is small and dorsal. The shell 
appears to have been exceptionally fragile, as all the specimens which 
I have seen, except one from the Tennessee locality, are very much 
distorted by pressure. 
Remarks.—I1 collected this fossil in August, 1877, at “ Mt. 
Parnassus,’ Columbia, Maury county, Tennessee; in 1879, at McKin- 
ney’s station, on the C. 8. R.R., Boyle county, Kentucky; and have 
since received it from my friend, Mr. W. M. Linney, of Harrodsburg, 
Kentucky, who collected it in Garrard county. At Columbia it was 
associated with Stellipora autheloidea, O. lynx, and Crania scabiosa, 
on the old redoubt excavation of ‘‘ Mt. Parnassus;” at McKinney’s. 
I collected with it Streptorhynchus filitextus, Ptilodictya hills, 
Murchisonia bellicincta, and undetermined corals, evidently belong- 
ing to the Cincinnati Group. At the Garrard county locality, it occurs 
with P. hilli, and a Rhynchonella, probably a variety of &. capazx. 
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