APPENDIX. 
321 
and haring a few slight concentric undulations inferiorly ; ligament slope very oblique, rectili¬ 
near, anterior extremity regularly rounded. 
Locality. —Canada de las Uvas, with the preceding species. 
6. c. alta, C nrad.—This species occurs in the same rock with the preceding, hut only in 
small fragments. It appears to have been abundant, as it likewise is at Claiborne, Alabama. 
The fracture has resulted from breaking the rock, as the shell appears to have been perfect and 
not water-worn. 
MYTILUS, Lin. 
7. m. humerus, Con., PL II, fig. 10.—Ovate, ventricose, summit acute ; anterior margin rec¬ 
tilinear ; basal margin rounded; anterior extremity less obtuse ; disk with minute radiating 
lines. 
Locality. —Canada de las Uvas, with the preceding fossils. 
CARDITA, Brug. 
8. c. planicosta, PI. II, fig. 6.—Obliquely cordate; ribs about 22, broad and flattened, 
separated by a narrow groove which becomes obsolete towards the base ; ribs on the posterior 
slope narrow, indistinct, and crossed by numerous profound wrinkles. Lunule small, cordate, 
profoundly impressed ; inner margine crenate. 
Locality. —Canada de las Uvas, with the preceding fossils. Venericardia planicosta Lara. 
An. Sans Vert. (Desh. ed.) vol. vi., p, 381. 
This common species occurs much larger, though less perfect, than the one represented. This 
shell occurs abundantly in the Eocene strata of Maryland, Virginia and Alabama, and is quite 
as characteristic of the American as of the European Eocene period. I discovered it in Mary¬ 
land in 1829, and at that time regarded it as the first indication of the occurrence of deposits in 
the United States synchronous with those of the London clay. Prof. Rogers has since named 
this shell Venericardia ascia. 
NATICA, Adamson. 
9. N. (ETITES? Con., PL II, fig. 7. 
Locality.— Canada de las Uvas, with the preceding fossils. 
N. cetites., Conrad.— Foss, shells of Tert. Form. October , 1833. 
10. n. gibbosa and semilunata, Lea. Cont. to Geol. December , 1833.—There is but one specimen 
of this shell, which I refer with doubt to a Claiborne species. The outline is similar to that of 
the latter, but the aperture is concealed in the rock, which prevents the necessary comparison to 
determine the identity or the difference. 
11. n. alveata, Con., Pl. II, fig. 8 and 8a.—Volutions 5, flattened above, carinated on the 
angle, a few minute obsolete lines revolve on the upper side of the whorls ; aperture inclining 
to an ohovate form ; umbilicas small. 
Locality ..—Canada de las Uvas. 
This species is remarkable for its truncated whorls, which are channelled by the carina on the 
margin. There are no analogous species in the Eocene of the Atlantic slope. 
TURRITELLA, Lam. 
12. t. uvasana, Con., Pl. II, fig. 12.—Subulate, whorls with the sides straight and oblique 
above, rounded below, and having large revolving striae with intermediate minute lines ; striae 
near the suture on the upper part of the whorls finer than the prominent lines below. 
41 F 
