42 
BULLETIN OF THE LABORATORIES 
ORACARDIA CORNUTA. sp. n. 
(Plate IV, Fig. 6.) 
Shell small, body subquadrate or semi-oval. Right valve (alone 
known) with the body nearly quadrangular but enormously produced 
at the umbo, to form the very high, strongly coiled beak which ex- 
tends half the height of shell above the hinge, which is straight, equal- 
ling the greatest length and bears the impress of the usual cartilage 
plate or ridge. The surface of the cast bears traces of numerous rad- 
iating and concentric striae. The shell might at first be taken for 
a Platyceras if the hinge were overlooked. Height, ii mm., length. 
9 mm. 
Immediately below congl. I with Palaeoneilo elliptica, 
CONOCARDIUM ALTERNISTRIATUM. sp. n. 
(Plate XI, Fig. 24 ; Plate V, Fig. 7. ?) 
Of medium. or large size for the genus, rather strongly convex. 
Lateral surface composed of two facets or curved, triangular planes 
separated by a more or less well-marked depression or groove, of these 
the anterior is strongly convex to the incurved beak, is about twice as 
wide as high and marked by about ten distant ribs which are separated 
by intervals wider than the ribs, both the depressions and the tops of 
the ribs being plane ; the posterior portion of the surface is less con- 
vex and longer than high and is marked by over twenty closely set and 
very irregular ribs, there is a tendency to alternation but frequently 
two or three of the smaller costae separate those of the larger set ; the 
ant-umbonal surface is heart-shaped in outline and rather strongly con- 
cave to near the projecting tubular projection, where it is strongly re- 
flexed, marked by 12-14 rather closely set arching ribs. Surface fine- 
ly marked by concentric strife especially between the ribs. 
All the specimens of this fine species seen were more or less dis- 
torted as is usual in this genus, hence it is not safe to rely too implicit- 
ly on proportions as seen in any specimens. 
Height of small specimen, 15 mm., length from umbonal ridge 
to posterior, about 16-18 mm., convexity of both valves, about 10 
mm. Height of a larger specimen along umbonal ridge, 24 mm. 
Bagdad and Burbank, Ohio, above the concretionary shales of 
Lodi. 
