Notes on Cincinnatian Fossil Types 
331 
Ohio, in 1893, so that the term Cymatonota typicalis has precedence. 
The specimen figured in this bulletin is 66 mm. long, 15 mm. 
high at the beak, 18 mm. high at the rear, and 11,5 mm. thick from 
valve to valve. The thickest part is near mid-length, or a short 
distance posterior to mid-length, and from this point the shell tapers 
gradually in both directions, gaping at the ends. Only the stronger 
concentric markings are preserved, the finer striations being absent. 
Oblique wrinkles border the hinge-line for a distance of 25 mm. 
posterior to the beak. The beaks are strongly flattened and ap- 
proach each other closely. Along the area marked by oblique 
wrinkles, the umbonal ridge diverges but moderately from the 
level of the hinge-line, and then curves more rapidly toward the 
lower posterior angle. The very shallow mesial depression extends 
for almost the entire length of the shell, producing a slight concave 
curvature along the basal margin of the shell. The anterior end 
of the shell is almost evenly rounded and extends about 13 mm. 
anterior to the beak. 
38. Modiolopsis versaillesensis, Miller 
{Plate IV, Fig. 4 ) 
Modiolopsis versaillesensis Miller, Cincinnati Quart. Jour. Sci., 1, p. 150,. 
Figs. 13, 19 
1891. Modiolopsis versaillesensis, Ulrich, Geol. Minnesota, 3, pt. 2, p. 521, Fig.^Oa 
Three left valves, numbered 8791 in the Faber collection at 
Chicago University, are labelled as Modiolopsis versaillesensis and 
as coming from Versailles, Indiana. Of these, the largest specimen 
is regarded as the original of figure 18 accompanying the original 
description, and another figure of the same specimen is presented 
in the present bulletin. All three specimens evidently came from 
the Cycloconcha milleri horizon in the Waynesville member at 
Versailles, Indiana. Compared with the figure presented by Miller, 
the beak is less prominent anteriorly; otherwise the agreement is 
quite close. The type is 45 mm. long, has a maximum height of 
25 mm., and the thickness from valve to valve is about 14 or 15 mm. 
judging from the convexity of the single valve here measured. 
Concentric striations are well marked along the anterior margin 
and along the post-umbonal slope near the hinge-line; along the* 
ventral margin of the shell they are only moderately distinct, and 
toward the umbonal ridge they frequently are faint. The shell is. 
only moderately convex. The umbonal ridge is distinctly but not 
