18 



BOOK OF SPECIES. 



B. CYLiNDRACEA (Pennant). Oblongs elon- 

 gated^ cylindric, transversely striated^ white ; ver- 

 tex umbilicated ; aperture suddenly dilated at its 

 base; columella flattened ; small. B. W. 18. 57- 



B. UMBLLiCATA (Moutagu) . Obloug, oval, 

 white, involute, minute, rounded, and umbilicated 

 at the apex. B. W. 18. 58. 



B. RETUSA (Montagu). Sub-cylindrical, in- 

 voluted, minute, striated longitudinally on the 

 upper part ; apex truncated and umbilicated ; the 

 aperture is most contracted in the middle. B. 

 minute. W. 18. 59. 



B. OBTUSA. Minute, cylindrical, involuted, 

 white, opaque, wrinkled longitudinally, and be- 

 coming rather narrow towards the apex; spire 

 somewhat prominent. B. W. 18. 00. 



LAPLYSIENS. 



LAPLYSIA. 



The animal with a dorsal, subcartilaginousy semi- 

 circular shield. 

 A. Petersoni. S. 254. 



DOLABELLA. 



Oblong, subarcuated, somewhat shaped like an axe, 

 on one side narrowed, thicker, callous, and sub- 



