RISSOIA-RISSOINA. 369 



R. ScHYTHET, Phil. Sts. of Mar/ellan. 



R. LAEVIGATA, R. :mucronata, R. tubercui.ata, R. truncata, 

 Menke, R. scrobiculata, Moll. Greenland. 



R. GRADATULA, R. EMACiATA, Morch. Wed Indies. 



R. CRASsicosTA, R. EULiMOiDES, R. ABERRANS, A. Ad. Jamaica. 

 R. INCOMPTA, Gould. Florida. 



R. Gentilissiana, Sowb. (PL 68, fig. 5). 



= Hydrohia Gentilsiana, Crosse. 

 R. BiciNGUi.ATA, and R. tenuicostata, Seguenza. Messina. 



R. Boscii, Payr. Corsica. 



R. PUNCTUM, Cantraine. Mediterranean. 



R. Weyville-Thompsoni, Jeffreys. Arctic Ocean. 



R. PEDicuLARis, Menke. Heligoland. 



R. PR^usTA, Recluz. Toulon. 



R. suBSTRiATA, aud R. ExiGUA, Phil. Sicily. 



R. DiLECTA, Monts. Sicily. 



R. scALARis, Mich. = Truncatella. 



R. GouGETi, Mich. Senegal. 



R. ELONGATA, R. EXCAVATA, Phil. = Odostoviia. 



R. EXiMiA, Jeffreys. = Odostomia. 



R. CooPERi, Tryon. = Amnicolidce. 



Genus RISSOINA, d'Orb. 1840. 



Section Rissoina (sensu stricto). 

 R. Inca, d'Orb. PI. 55, fig. 15. 



Strong, stout, with about 17 elevated, suboblique, flexuous, longi- 

 tudinal ribs, and fii>e spiral strise, more prominent on the base; 

 Avhorls 7-8, nearly flat, suture crenulated; rosy white. 

 Length 8-2 mill. 



Bolivia, Peru. 

 R. PYRAMIDALIS, A. Ad. PI. 55 fig. 16. 



Bolid, dirty white, longitudinally obliquely plicate, spirally striate, 

 whorls 8, flattened, suture crenulated. Length, 8*5 mill. 



Philippines. 

 R. AssiMiLis, Jickeli. PI. 68, fig. 15. 



Shell solid, white, with 10-11, straight, narrow, longitudinal 

 costse, and much wider interstices, Avhich show slight, distinct spiral 

 strjte; whorls 8, slightly convex, with impressed sutui'e; lip scarcely 

 varicose. Length, 8*3 mill. 



Red Sea. 

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