Fossil and Recent Shells. 343 



LUCINA. 



1. L. pandaia. Shell oval, compressed, obscurely cancellated ; 

 anterior side somewhat corrugated ; beaks nearly central ; teeih three 

 in one valve ; anterior muscular impression profoundly elongated; 

 lunule excavated, minute. Length, one inch and one fourth. 



Locality. — Claiborne, Alab. London clay. This shell is allied 

 to Lucina mutabilis, Lam. 



2. L. dolahra. Shell elevated, with distant concentric imbrica- 

 ted and obscure radiating striae ; posterior submargin profoundly chan- 

 neled, beaks prominent and curved forwards; lunule impressed, cor- 

 date; inner margin crenulated. Length, half an inch. 



Locality. — Claiborne, Alab. London clay. 



CYTHEREA. 



C. Marylandica. Shell obtusely ovate, smooth, thick ; umbo 

 obtusely rounded posteriorly; lunule ovate-acute and slightly impres- 

 sed; hinge with the anterior tooth very robust. 



This shell is from the upper marine formation; it is about the size 

 and shape of Venus mercenaria, and is vastly abundant in the bank of 

 the Choptank river, about four miles from Easton, Md. and occurs 

 in no other locality which I have visited. 



NUCULA. 



1. JY. bella. Shell ovate elongated, rostrated, with numerous 

 regular concentric striae, and two carinated lines on the anterior sub- 

 margin diverging from the apex; on the posterior side is a slight fur- 

 row from the apex to the base. Length, half an inch. 



Locality. — Claiborne, Alab. London clay. 



2. JV. ccelata. Shell ovate elongated, with .irregular undulated 

 ridges ; anterior sub-margin with three minutely crenulated carinated 

 lines diverging from the apex; beaks nearly central. Length, half 

 an inch. 



Locality. — Found with the preceding species. 



FUI.GUR. 



.F. incilis. Shell fusiform, with coarse alternated with finer spi- 

 ral striae; spire elevated ; whorls five, rounded, flattened a little above, 

 but crowned with a carinated line; suture broadly and profoundly 

 channeled ; body whorl ventricose. 



Locality. — Yorktown, Va. Upper marine. 



This shell is about the size of F. canaliculatus, which it distantly 

 resembles. 



