OF CONCHOLOGY. 



259 



NATICA, Lara. 



N. PLICATELLA, Conrad. — PL 24, fig. 3. 



iV. canrena, Conrad (not Lam.), Amer. Jour, of Science and 

 Arts, vol. xli. p. 344. 



NEVERITA, Risso. 



N. ExMMONSii. — PI. 24, fig. 2. 



Thick ; spire depressed ; umbilicus perfectly closed by a thick 

 rugose callus. 



Natica Emmons. Geol. of N. Carolina, p. 267, fig. 151. 



N. DENSATA. PI. 24, fig. 5. 



Description. — Ovate, thick, prominent and pyramidal by com- 

 pression of the whorls ; surface marked by very minute obsolete 

 revolving lines ; umbilicus nearly closed by a thick rugose callus. 



Natica duplicata, Conrad (not Say), Emmons, Geol. of North 

 Carolina, p. 266, fig. 150. 



MELANIID^. 



MELANOPSIS, Ferussac. 



The three species of a genus which I supposed to be marine 

 and named BuUiopsis, are probably fresh water shells of the 

 genus 31elanopsis. These and one species of Vivipara are all 

 the fresh water shells yet found in the Atlantic slope Miocene. 



M. 3Iari/Iandica, 31. quadrata, and 31. Integra. See vol. ii., 

 p. 65 of this Journal. 



CASSIDiE. 



SEMICASSIS, Klein. 



S. C^LATA.— PI. 21, fig. 3. 



Journal of the Acad. Nat. Science, Vol. vi., p. 218, pl. 9, 

 fig. 14. 



This is a very rare shell of a genus unknown on the Atlantic 

 coast, the species chiefly inhabiting the eastern seas. 



SCALARIDiE. 



SCALARIA, Lam. 

 Qnhgenas STHENOBYTIS, Conrad. 

 S. PACHYPLEURA. — PI. 21, fig. 4. 



Descripition. — Short, conical, whorls 8 ; spire acuminate ; 



