22 PLEIOCENE FOSSILS. 



Yam. CHAMACLD^E. 



CHAM A.— Linn. 



CHAMA CORTICOSA.— Con. 



Plate VII, Figs. 1, 2, 3. 



Chama corticosa, Con., Am. Jour. Sci., Vol. XXIIL, p. 341, Foss. Ter. For., p. 32, pi. XVII. fig. 3. 



C. testa sinistrorsa, inbricata-lamellosa ; valva superiors operculiformi, convexiuscula, 

 radiatim striata, valva inferiore convexa, contorta. 



Description. Shell sinistral, lamellar, imbricate ; upper valve flat or somewhat convex, 

 marked with radiating lines ; lower valve convex, contorted. Readily distinguished by its 

 sinistral beaks, and whole surface covered by coarse scales, in concentric layers. 



This fossil, so abundant in the Meiocene of Virginia, is quite rare in South Carolina, only 

 a single valve having been found. 



Plate VII., Fig. 1. Lower valve, natural size. 

 " 2. View of fossil from aoove. 

 " 3. Side view of the same. 

 " 2 and 3 are from the Meiocene of Virginia. 



Locality. Darlington District. 



Museum, College of Charleston, 8. C. 



CHAMA ARCLNELLA.— Linn. 



Plate VII., Figs. 4. 5, 6. 



Charna arcinella, Linn., Sys. K"at. p. 1139. 



C. testa orbiculo-cordata ; costis radiatim spinosissimis, interstitiis excavato-punctatis. 



Description. Shell orbicular-cordate ; radiating ribs very spinous ; spines strong, re- 

 curved, tubular ; interstices deep, punctate in young specimens ; lunule broadly cordate ; 

 buccal side granulated. 



