END ' 
tricose, smooth : posterior slope suddenly depressed ; umbonsl slope angu 
litr , posterior end truncated. 
L rolls' A. Brag, 
L. glelmla pi. 1, fig, IS. Shell rounded oval, convex, concentrically 
laminated ; anterior end truncated, direct ; posterior end emarginate ; pos- 
terior slope suddenly depressed. 
One valve only was found 
CARDIUM. Lin, 
“unu ENr teach re ar mr m . 
C. Caml/h-i iwB, pi. tig. 1. Shell elevated, slightly oblique, ventiii 
cose : ribs about thirty to the mnbonal slope, convex, little prominent 
close, die intervening spaces linear, ribs transversely 'rugose : ribs on pos- 
terior slope large, angular, subearinated ; cardinal and lateral teeth promi- 
nent : cardinal teeth equal in length. 
Hare, 1 ■ • ribs *loser than represented in the outline figure. 
PIIOTOC ARt>3 \ Ticyrhh 
P Carotin nsis, pi 2, fig. 21. Shell rounded, direct, equilateral, ventri- 
cose: umbo broad, summit prominent; nmborial slope undefined ; poste- 
rior slope slightly impressed or concave, with eight rather wide, little 
prominent, flattened ribs; disk with minute, close, concentric, impressed 
lines, largest towards the base : anterior lateral tooth distant, very promi 
nent; posterior tooth small. 
Only one valve has been obtained. It differs from P. JJAUammt, 
S< w< rby in having larger and much fewer ribs posteric rly. 
\ Pi ! ROM N A Conrad 
When ! defined this genus 1 knev. one species onlv, but my visit t 
Snow Hill i aled a nm’cb larger and be ttei eh a r t ■ teri e< p< ies and 
diiily justities the separation of a group of Cretaceous shells from Oytueeiea, 
strix. C ah vat is or VfeNns do not occnrin American Cretaccons strata. 
A. regia, pi.. 2, fig. 7. Shell ovato-triangular, very inequilateral, 
re'ntricose. thick in substance, umbo oblique, lunule lanceolate, defined bv 
