Occasional Papers of the Ahiseiiiii of Zoologx 7 



I have not seen specimens of typical bonairciisis (E. A. 

 Smith, 1898). but it is certainly a smaller shell. The indi- 

 viduals of cnracoana figured show the extremes in variation 

 of size and shape. They measure : 



The raduke of two alcoholic specimens were examined 

 (fig. 5). The formula is C i/i ; I 37/2 + i/i =38—1—38. 

 The central has a single heavy cusp. The laterals have a 

 broad, thin blade (mesocone), and a stout, recurved aculeate, 

 smaller one (entocone). The edge of the mesoconal blade 

 from the 7th out is quite, noticeably concave near the tip. The 

 base of each of the teeth is narrow^ elongate and poorly lim- 

 ited posteriad ; that of the laterals is divided longitudinally, ex- 

 cept near the base, by a groove which runs up to between the 

 cusps. The outermost teeth are reduced in size ; the last is 

 little more than a mere denticle. This radula appears closest 

 to that of M. pontificiis (Gould), as figured by Pilsbry (1904). 



BrachypodcUa ravoii ("Bland" Crosse) (1872). 



Thirty-two specimens, some living; from underside of rocks. 



CERIONID.li 

 Ccrioii inv (Linn.) (1758). 



Very abundant; cemented to the rocks and the lower por- 

 tions of the vegetation. None of my specimens belong to the 

 var. dcsculptum Pilsbry and Vanatta (1896). 



