FROM THE TERTIARY OF VIRGINIA. 29 



Length .16. Breadth .25 of an inch. 



Remarks. The flattened whorls and incrassated outer lip at once distinguish this 

 shell from all its congeners. 



FAMILY PLICACHLE. 

 GENUS ACTEON. 



A. GRANULATUS, Pi. 36. FlG. 54. 



A. testa subulatd, crassd, sub-perforatd, noduloso-costatd; spird elevatd, obtusd, mamillatd, ad apicem politd ; suturis im- 

 pressis; anfractibus sex, convexis; costis transversalibus, planis, regulariter nodulosis, und lavi prope suturam inferiorem; 

 anfractu ultimo rotundato; perforation* minima; basi costatd; aperturd ovatd, superne angulatd, sub-effusd; plied columellari 

 magnd, acutd. 



Shell subulate, thick, sub-perforate, nodulously costate; spire elevated, obtuse, mamillate, polished at the apex'; 

 sutures impressed; whorls six, convex; ribs transverse, flat, regularly nodulous, a smooth one near the lower suture; 

 last whorl rounded; base costate; perforation very small; mouth ovate, angular above, somewhat effuse; fold on the 

 columella large, acute. 



Length .18. Breadth .08 of an inch. 



Remarks. The nodules on the ribs are small and in regular order, giving the shell a 

 granulate and cancellated appearance. The fold on the columella is placed about the 

 middle, and is quite large. The mouth is rounded below and acutely angular above. On 

 the body whorl the ribs are about eight in number, while there are five on those of the 

 spire. The basal costse are smooth and smaller. 



Judging from description, this shell is not unlike A. pomilius and A. idoneus, Conrad; 

 but may be distinguished by the perforation, mamillate apex, and the smooth rib near 

 the lower suture. 



A. GLOBOSITS, PL. 36. FIG. 55. 



A. testa ovatd, crassd, cancellatd, umbilicatd; spird brcvi, ad apicem leevi et politd; suturis pan-is; anfractibus tribus, con- 

 vexis, rapide crescentibus, supra planulatis; costis octo, transversis, magnis; striis longitudinalibus, parvis, irregularibus; 

 anfractu ultimo rotundato; basi cancellatd; umbilico magno; aperturd magnd, sub-ellipticd; columella recta; plica columellari 

 magnd, acutd. 



Shell ovate, thick, cancellate, umbilicate; spire short, smooth and polished at the apex; sutures small; whorls 

 three, rapidly increasing, convex, flattened above; costas eight, transverse, large; striae longitudinal, small, irregular ; 

 last whorl rounded ; base cancellate; umbilicus large; aperture large, sub.elliptical; columella straight; fold on the 

 columella large, acute. 



Length .10. Breadth .08 of an inch. 



Remarks. The longitudinal striae occasionally do not cross the ribs, which, in. that 

 case, are rounded and polished. The mouth is somewhat semicircular, with the colu- 

 mella for a base. On the upper whorls there are but four ribs, the rest being concealed 

 by the succeeding growth. About a whorl and a half near the apex, are perfectly 

 smooth. 



This is a very pretty little shell, and bears no decided resemblance to any of our fossil 

 species. It is unusually globose for an Acteon, but can. hardly be placed in the kindred 

 genus Tornatelfa, 





