78 RISSOID^. 



20. Rissoina plicata. 



Rissoina plicata, A. Adams, P. Zool. S. 1851, 1. Mashate ; Schwartz, I. c.fig. 

 21 [typical specl, long. 5'6, diam.2'5 mil.; var. = R. scalariana, A. 

 Ad. and R. hertheloti, Audouin. 



50 Andamans, Arakan, Kharg, Mauritius, Bourbon, Seychelles ; coll. W. 

 T. Blanford and G. Nevill, Esqrs. 



10 Ceylon; coll. G. Nevill, Esq. [6,2f— apex perfect]. 



These Ceylon specimens approximate very closely to var. 

 B. hertheloti. 



1 Viti-Levu j ex Mus. Godeffroy [as " R.firmata, C. B. Ad."] 



A true, typical B. plicata, and not in the least like the W. 

 Indian B. firmata. 



2 New Caledonia ; ex c. P. Bouvier, Esq. 



subvar. diplostoma. 

 1 Ceylon ; coll. G. Nevill, Esq. 



21. Rissoina scalariana. 



Rissoina scalariana, A. Adams, P. Zool. S. 1861, Philippines ; fide Schwartz, 

 long. 8kt diam. 8\ mil. 



1 Roweiah [Red Sea] ; coll. J. B. Baxter Esq. 



4 Mauritius, and Kharg [Persian G.]; coll. W. T. Blanford and 

 G. Nevill, Esqrs. 



Possibly better classed as a variety of B. plicata. 



22. Rissoina bertheloti. 



Rissoina bertheloti, Audouin, Descr. de VEgypte, 1826, pi. IV, fig. 2. 



Long. 8|, diam. 3| mil. 



1 Kesm ; coll. W. T. Blanford, Esq. 

 20 Roweiah and Aden j coll. J. B. Baxter and G. Nevill, Esqrs. 



subvar. minor. 



Long. 5, diam. 2,-}^ mil. 



3 Roweiah, Red Sea ; coll. J. B. Baxter, Esq. 



