Preliminary Notes on Cincinnatian Fossils 
219 
The specimen illustrated by figs. 2a, 2 h, 2e, 2/ and 2 g may repre- 
sent the large form of Dalmanella multi secta, if such a form exists; 
but, as far as may be determined from the figures, it appears to 
have been a good specimen of Dalmanella jugosa, from the Waynes- 
ville bed. While there may be large specimens of Dalmanella 
multisectay in the Upper Eden, it does not seem likely that any of 
these would have dorsal valves as strongly convex as the one rep- 
resented by figs. 2 e and 2/. 
Miller regarded Meek’s statement concerning the horizon at 
which the specimens illustrated by figs. 2a to 2 g were found as in 
error, and expressed the belief that these specimens came from 
Hamilton, in Butler county, Ohio. In fact, he states that the 
typical specimens 2a to 2 g are quite common at the quarries in 
Hamilton, Butler county, associated with Orthis ella, Orthis bellula, 
Orthis fissicosta, Orthis plicatella, Orthis sinuata, Glyptocrinus 
decadactylus, and other species indicative of a range from 300 to 
400 feet above low water mark, at Cincinnati; in other words, in 
the Fairmount beds. Since only the form here described as Dal- 
rnanella fairmountensis is common at this horizon at Hamilton, J. 
Mickleborough and A. G. Wetherby in their catalogue of Lower 
Silurian Fossils of the Cincinnati group, published in 1878, list 
Orthis meeki as a variety of Orthis emacerata; and James, in 1879, 
in the Supplement to his catalogue, regards it merely as a synonym 
of Orthis emacerata. That this is in error is shown by Miller, in 
his description of Orthis multisecta, in the same volume of the Cin- 
cinnati Quarterly Journal of Science y where he states of Orthis 
multisecta: ‘fit is abundant at nearly all exposures from low 
water mark, at Cincinnati, to 250 feet above; after this, as we 
ascend in the strata the form which I have called Orthis meeki 
prevails in its stead. It would be impossible to determine 
where one form begins and the other ends, as they clearly 
intermingle, and leave the constantly recurring impression that 
they are not specifically distinct.” Under his description of 
Orthis meekly on the contrary, he states that this species can be 
readily distinguished from Orthis emacerata. That Miller was 
familiar with Dalmanella emacerata is shown by his statements 
that this species was found on Columbia avenue and on the Tor- 
rence road, 160 feet above low water mark, and was not known 
over 200 feet above low water mark, at Cincinnati. This is ihe 
Middle Eden horizon, at which Dalmanella emacerata is rather 
widely distributed. 
