276 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXII 



Examples: Neritaoryzarnm, Hecluz. (fig. 11); Astralvam stellatum, 

 Gmelin, belonging to the Turhinidce (fig. 12) and Polydonta radicda, 

 Gmelin, belonging to the Trochidce (Plate, fig. 3, and Text, fig. 13). 



Fig. 12. 





Fig. 13. 



The .formula for JS'erita may be stated as oo • 3 • 1 • 3 • oo if the 

 large capitmliform tooth next the marginals be regarded as a lateral, 

 'That for Astralium and Polydonta is in each case oo • 5 • 1 • 5 • oo All 

 these I'adnlae consist of a large number of rows, only a couple of 

 rows are illustrated in the figures. 



Other species in the collection are Turbo elegans, Phil., Clanculus 

 scahrosiis, Phil., and Euchelus indicas, A. Adams. The two latter 

 belong to the Trochidce. 



