BULLA. 



17 



B. APLUSTRE. Roundish ovate^ white, with 

 two flesh-coloured, bordered zones ; pillar some- 

 what twisted ; spire elevated and retuse. f . W. 

 18. 26. 



B. HYDATis. Ovate-rounded, thin, pellucid, 

 and slightly striated longitudinally, yellowish 

 horn-colour. | ; in shape resembling somewhat 

 B. naucum. B. W. 18. 17. 



B. NAUCUM. White, rounded, pellucid, finely 

 striated transversely, and umbilicated at both 

 ends. li...l. W. 18. 12. 



B. SOLID A. Cylindrical, white, umbilicated 

 at the apex, and striated at the two extremities ; 

 aperture extending the whole length of the shell. 

 |. W. 18. 56. 



B. AUSTRALis. Elongated, nearly cylindri- 

 cal, mottled ; spire very slightly perforated -, in 

 colour greatly resembling B. ampulla, IJ. 



