TELLINIDiE. 49 



This shell is common along the whole Atlantic coast of the United States, but very rare 

 in the Post-Pleiocene beds of South-Carolina. 



Plate VIII. Fig. 5. 



Locality. Simmons'. Museum, College of Charleston; Cabinet F. S. H. 



Genus, SERRULA.-Linn. 



SERRULA VARIABILIS. 



Plate VIII. Fig. 6. 



Donax variabilis, Say, Jour. Acad. Nat. Sci., Vol. 2, p. 305. 



Donax variabilis, Say, Am. Conch., pi. 61, fig. 1. 



Donax variabilis, Be Kay, Zool. New- York, Art, Mollusca, p. 212. 



Donax variabilis, Ravenel, Cat. Coll. Shells, p. 4. 



Donax variabilis, L. R. Gibbes, Tuomey's Geol. So. Ca., appendix, p. xxi. 



Donax variabilis, Tuomey 4- Holmes, Pleiocene Foss. So. Ca., p. 95, pi. 23, fig. 6. 



Serrula variabilis, Adams, Gen. of Recent Shells, Vol. 2, p. 406. 



Donax variabilis, Say's Conch, of U. S., (Binney,) pp. 99, 226. 



Description. Shell triangular; longitudinally striated, with equal, parallel, regular, 

 impressed, but indistinct lines; buccal margin obliquely truncated, cordate, suture sub- 

 convex; anal margin nearly rectilinear, suture indented; pallia! margin a little prominent, 

 beyond a regular curve, near the middle; interior edge crenate. — T. S? B. 



This is an abundant recent species upon the sea shores of the South, and is found fossil 

 also in great quantities in the Post-Pleiocene beds. 



Plate VIII. Fig. 6, Fossil, natural size. 



Locality. Abbapoola; Simmons'. 



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



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