OF DENISON UNIVERSITY. 
25 
Although very constant in form, this species varies greatly in size. 
The small forms resemble T. linckl^i, H. It differs, if at all, in hav- 
ing the anterior truncation rather more pronounced. The resemblance 
approaches identity. 
Moods run, 70 feet below congl. I, Ashland Co. , 70 feet below 
coiigl. I, and Lodi, Medina Co. 
RHYNCHOSPIRA (?) ASHLANDENSIS, Sp. n. 
(Plate III, Fig. 16.) 
A small Rhetzia-like species from the horizon seventy feet below 
conglomerate I, occurs near Lyon Falls, ^Ashland Co. 
Shell small, broadly sub-oval, with the greatest..convexity of the 
valves above the middle, and the beak of the ventral valves produced 
beyond its fellow, perforate. 
Ventral valve with a strong, narrow, mesial elevation proceeding 
from the beak to the front where it gradually expands, passing into 
the general surface at the front which is sinuous ; lateral surface de- 
pressed, beak strongly projecting, length and width about equal, sur- 
face marked by about twenty rather abrubtly elevated simple ribs, sep- 
arated by curved depressions. Dorsal valve wider than long, with a 
shallow mesial sinus which widens below, lateral surfaces convex. 
Length, 6. 5 mm. 
As nothing is known of the interior the generic reference is but 
provisional. 
SPIRIFER BIPLICATUS, Hall. 
(Plate II, Fig. 8.) 
Examination of a large suite of specimens happily removes all 
doubt as to the position and specific identity of this species. The spe- 
cies has been peculiarly unfortunate in the illustrations hitherto given 
with the descriptions. 
Meek’s figure in the Ohio Paleontology is quite unrecognizable. 
There is comparatively little variation in our series. Meek’s descrip- 
tion applies well but it is unusual for more than four plice to occupy 
the fold and these are distinctly paired. The mucronate hinge is also 
constant and forms an easy distinguishing character from S. striatifor- 
