C A R D I A D .'E . 23 



Genus, CHAMA. — Linn. 



GUAM A A 11 C I N E L L A . 

 Plate V. Fig. 1. 



Chama arcinella, Linn, Syst. Nat., p. 1139. 



Chama arcinella, L. R. Gibbes, Tuomey's Geol. So. Ca., appendix, p. xxii. 



Chama arcinella, Ravenel, Cat. Coll. Shells, p. 7. 



Chama arcinella, Tuomey c^ Holmes, Pleiocene Foss. So. Ca., p. 22, pi. 7, figs. 4, 5, 6. 



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

 tubular; interstices deep, punctate in young specimens; lunula broadly cordate, buccal 

 side granulated. — T. 6^ H. 



A few specimens of very young shells, not spinous, but granulated, and with very 

 indistinct characters, have been taken from the Post-Pleiocene sands of South-Carolina. 

 It is rare in the living state upon the coast, but common on the Florida shores. The 

 Pleiocene specimens are very large, with prominent spines. 



Plate V. Fig. 1, Natural size. 



Locality. Simmons'; Wadmalaw Sound. 



Museum, College of Charleston ; Cabinet F. S. H. 



CAllDIADJ;. 



Genus, C A R D I U M . — L in n. 



C A R D I U M MAGNUM. 

 Plate V. Figs. 2 ..\.\d 2a. 



Cardium magnum. Born., Test. Mus. Coes. Vind, pi. 3, fig. 5. 



Cardium magnum, Tuomey t^- Holmes, Pleiocene Foss. So. Ca., p. 03, pi. I'J, fig. ]. 



Cardium maculatum, Gmelin, Conch. Icon., pi. 4, fig. 20. 



Cardium maculatum, Ravenel, Cat. Coll. Shells, p. 5. 



Cardium ventricosum, Bruguiere, Lam., An sans Vert., Vol. G, p. 400. 



Cardium ventricosum, De Kay, Zool. New-York, Art. Mollusca, p. 207. 



Cardium ventricosum, L. R. Gibbes, Tuomey's Geol. So. Ca., appendix, p. xxi. 



Description. Shell very large, inflated, obliquely cordate ; anal side somewhat angu- 

 larly depressed; radiately ribbed; ribs flattened, buccal ribs crenulated. 



