RISSOIA-RISSOINA. 369 



R. SCHYTHEI, Phil. Sts. of Magellan. 



R. L^VIGATA, R. MUCRONATA, R. TUBERCULATA, R. TRUNCATA, 



Menke, R. SCROBICULATA, Moll. Greenland. 



R. GRADATULA, R. EMACiATA, Morch. West Indies. 



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

 R. INCOMPTA, Gould. Florida. 



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



= Hydrobia Gentilsiana, Crosse. 



R. BICINGULATA, and R. TENUICOSTATA, Seguenza. 'Messina. 



R. Boscn, Payr. Corsica. 



R. PUNCTUM, Cantraine. Mediterranean. 



R. WEYVILLE-THOMPSONI, Jeffreys. Arctic Ocean. 



R. PEDICULARIS, Menke. Heligoland. 



R. PR^EUSTA, Recluz. Toulon. 



R. SUBSTRIATA, and R. EXIGUA, Phil. Sicily. 



R. DILECTA, Monts. Sicily. 



R. SCALARIS, Mich. = Truncatella. 



R. GOUGETI, Mich. Senegal. 



R. ELONGATA, R. EXCAVATA, Phil. = Odostomia. 



R. EXIMIA, Jeffreys. = Odostomia. 



R. COOPERI, Tryon. = Amnicolido3. 



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 fine spiral strise, more prominent on the base; 

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



Length 8'2 mill. 



Bolivia, Peru. 



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



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

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



Philippines. 



R. ASSIMILIS, Jickeli. PL 68, fig. 15. 



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

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

 stre; whorls 8, slightly convex, with impressed suture; lip scarcely 

 varicose. Length, 8*3 mill. 



Red Sea. 

 24 



