112 THE ELEMENTS 



Fig. 12th. -CONUS VARIA. Rub- 

 bed through on one side to show the 

 internal structure of the shell. 



D spire, F body, MMM pillar or 

 columella. 



PLATE III. 



Fitr. 3d...-TROCHUS UMBILI- 

 CATUS. Shell conico-convex, flat- 

 tish, rounded at the top ; apex depres- 

 sed, volutions five, slightly emarginate, 

 defined by a fine line ; spirally striate, 

 rather whitish, with zigzag lines of 

 purple ; aperture compressed and an- 

 gulated ; with a large umbilicus which 

 extends to the apex. Found on the 

 Northumberland and Yorkshire coasts. 



Linn. Trans, vol. viii. page 153. 



C Aperture, ?7 umbilicus. 



Fig. 2d.-HELIX NEMORALIS. 

 Shell imperforate sub-globose, thia 



