of a rare Species of Worm Shells. 
275 
Plate XL 
Fig. 6, Represents the internal cavity of the shell at its 
lower part, which is every where smooth ; it also shews how 
very thin the shell is which closes up the extremity, compared 
with that of the general tube, which is also thinnest at the 
lowest part. 
Fig. 7 , A section of a specimen which had the tuberculated 
appearance on its internal surface* 
