RISSOIDiE. 75 



4. Rissoina indica, n. sp. 



1 Paumben Straits, South India [type]; coll. F. Armstrong, Esq. 



Another very beautiful, sHning, " Mangelia-like " form, 

 dredged alive in 35 fathoms ; it is not unlike B. terehra, Garrett, 

 PI. §5 fig. 11, of the Proc. Acad. Philad., and also resembles B. 

 incerta, Souverbie ! It has eight perfectly "planulate " whorls, 

 the apical one smooth, the others with perfectly perpendicular, 

 regular, very massive ribs, otherwise smooth ; columella and 

 interior of aperture stained brown, scarcely notched at base, 

 outer margin white and remarkably thickened. 



Long. 5, diam. If mil. 



5. Rissoina subdebilis. 



Rissoina subdebilis, Nevill ms., Weinlcauff, Co7ich.-Cah. TI,1SS1, pi. 15 B, 

 Jiff 9) Maurititis. 



20 Mauritius (type) ; coll. G. Nevill, Esq. 



May possibly prove to be a large, cylindrical, subangulate 

 variety of B. dehilis, Garrett, P. Acad. Philad. 1873, pi. 2, fig. 9. 



Long. 6, diam. 2| mil. 



var. perlanceolata [? dist. sp.] 



1 Mauritius (type var.) ; coll. G. Nevill, Esq. 

 A well-marked form with ten whorls. 



6. Rissoina, n. sp. 



5 Kesm (Persian G.) ; coll. W. T. Blanford, Esq. 



Somewhat resembles the fossil B, grateloujjiy Orbigny. 

 Long. 3|, diam. IJ mil. 



? var. [? dist. sp.] 



1 Seychelles ; coll. G. Nevill, Esq. 

 Long. 4, diam. If mil. 



? var. [? dist. sp.] 



2 New Caledonia; exc. P. Bouvier, Esq. 



