POTAMIDES. 163 



C. RissoiDEA, Sowb. PI. 33, fig. 78. 



With curved, longitiulinul, oblique ribs, which are noduliferous 

 beneath ; Avhorls convex, base spirally ribbed ; brown, the ribs 

 whitish; Length, 19 mill. 



Port Natal, So. Africa. 



a MoRCHi, A. Ad. PI. 33, fig. 68. 



Rather thin, glaucous, more or less spirally lined with red ; lon- 

 gitudinally rather faintly ribbed, closely spirally ridged ; apex 

 decollated. Length, 1 in. 



Philippines. 



C. TURRiTELLA, Quoy. PI. 34, figs. 93, 94. 



Chestnut colored or lighter, often with a white band, granulated 

 in three or four spiral rows by decussating sculpture, lower part of 

 body whorl with revolving riblets only. Length, 1 in. 



Australia. 



Almost exactly like C. conica, Blainv., of the Mediterranean Sea, 

 as to form and sculpture ; the base is longer and more rounded, and 

 it has not the iufrasutural w'hite band of that species. 



C, BicARiNATA, Gray. PI. 35, figs. 15, 16. 



Obscurely, distantly, longitudinally, narroAvly plicate, spirally 

 striate, base defined by a double ridge ; chocolate color, white at 

 the suture, interior brownish. Length, 1 in. 



New Zealand. 



C. lutulentum, Kiener, is a synonym. 



Var. suBCARiNATA, Sowb. Fig. 16. 



Base with three ridges. 



C. Australis, Gray (not Lam.), and C. nigra, Hombr. et Jacq., 

 are considered synonyms by Hutton. 



C. scALARiFORMis, Say. PI. 33, figs. 78, 75, 76. 



Whorls slopingly convex, the well impressed suture usually 

 defined by a narrow thread, with numerous, close longitudinal 

 riblets, and less distinct S2)iral sculpture, base of body whorl with 

 spiral riblets only ; whitish, glaucous; light fawii color to chocolate, 

 the lighter colored specimens often Avith chocolate, the darker ones 

 with whitish lines ; aj^erture like the exterior. Length, 1 in. 



Florida. 



C. tenuis, Pfr. (fig. 76), is very probably a young shell of this 

 species. 



