30I 



Bulletin 5 3i 



FOSSIL SHELLS. 1 25 



TURRlTEIvLA. 



T. plebeia. PI. vii. fig. i. Whorls convex, 

 hardly flattened in the middle, with about twelve 

 revolving elevated striae, the middle ones alter- 

 nately somewhat smaller ; transverse wrinkles dis- 

 tinct. 



This shell seems to attain to the' length of rather 

 more than one inch. Several specimens are im- 

 bedded in a small mass of light lead coloured clay. 

 It somewhat resembles T. brevis of Sowerby, but 

 the strise are not crenulated. A species of TuRRi- 

 TELLA was found by Mr. A. Jessup in New Jersey, 

 quite different from the present species, and resem- 

 bling the T. conoida, Sowerby, but much smaller. 



NATICA. 



N. interna. Pi. vii. fig. 2. Subglobose, de- 

 pressed, subglabrous ; umbilicus open, with a re- 

 volving rib. 



Description. Shell destitute of revolving strise, 

 and the wrinkles are not prominent, except near 

 the suture, towards the labrum, and on the verge 

 of the umbilicus : spire but little prominent, acute : 

 aperture subovate : umbilicus open, permitting a 

 view nearly to the inner tip of the spire ; a revolv- 

 ing rib above the middle of each volution, termi- 

 nating at the labrum in a hardly prominent callus. 

 [J. A. N. S., Phila., ist Ser., Vol. IV, 1824.] 



