24 PLEIOCENE FOSSILS. 



Fam. PECTINLDiE. 



SPONDYLUS.— Gesner. 



Casts from the shells of this genus are found in the beds on Goose Creek, but are too 

 imperfect for description. 



Locality. Goose Creek. Prof. L. R. Gibbes. 



PLICATULA.— Linn. 

 PLICATULA MARGINATA.— Say. 



Plate VII., Figs. 11, 12, 13 and 11. 



Plicatula marginata, Say., Jour. Ac. Nat. Sci., A r ol. IY., p. 136, pi. 9, fig. 4. 

 Plicatula marginata, Con., Fos. Ter. Form. p. 15, pi. 13, fig. 5. 



P. testa ovato-cuneata, irregulari, crassa, subcequivalvi, radiatim 3-5-costata • costis elevatis, 

 lamellosis. 



Description. Shell ovate, wedge-shaped, irregular, thick, nearly equi-valve; radiately 

 three to five costate ; ribs elevated, lamellar. 



The ribs vary in number, and like its living congener P. ramosa, it has sometimes, to- 

 wards the palleal margin, one or two short ribs between the longer ones. 



In full grown specimens a raised and slightly crenulated line, borders the margin of the 

 shell on the inside. 



From P. ramosa, Lam., of our Southern coast, it is distinguished by its coarse, lamellar 

 ribs, and greater thickness. The genus Plicatula is found in the lower Jurassic rocks, and 

 occurs through all the intermediate periods, up to the present, in which it inhabits the 

 shallow waters of the ocean in warm climates. 



Plate YLL, Fig. 11. Upper view of fossil, natural size. 



" 12. Side view of same. 



" 13. Front view of same. 



" 14. Interior of ooth valves. 



Locality. Darlington District, S. C. 



Museum, College of Charleston, S. C. 



