vious lunhilicus : the colour whitifhj tranfparent aii4 

 glofTy. From Reculver, very rare. 



This is rather fmaller than the laft, and differs from it 

 in the turn of the lefTer end, where it only makes one 

 volution, -which is open or pervious. 



Serpula bicornis, Tiirt. Lin. iv. p. 609. BicoRxn^ 



Adams. Microfc. t. 14. f: 2. 

 Serpula bicornis ventricofa. Walk. Min. SheUs. f. 



o 



The belHed femi-lunar Wormfhell ; colour white, 

 opaque and glolTy. From Sandzvich and Rcculver, 

 though not common. Length one line. 



We received this fpecies from Mr. Boys for that de- 

 fcribed by Walker, the figure of which does not exact- 

 ly exprefs the formation of the fliell, which reprefents 

 only two compartments, whereas it has three : the mid- 

 dle one is extremely fmall, fometim.es raifed, at other 

 times depreffed : is fub-oval, comprelTed, and ftnated 

 longitudinally on the longer fide from the aperture ; the 

 crther fide is fmooth : it contracts towards tlie mouth, 

 which is very fmall and orbicular. 



Serpula perforata. Turt Lin. Iv. p. 509- Perforatu.u. 



A Jams. Mxrcfc. t. 14. f. 3. 

 Serpula bicornis uinbiico perforato. JVdk. Min, Shells, f. 3. 



The . 



