XIV 



acuticarinata, Lea. catenoides, Lea. 



cq^is, Lea. elevata, Lea. 



bella, Conrad. Jilum, Lea. 



Hoykrm'ana, Lea. Holstonia, Lea. 



caliginosa, Lea. noclulosa, Lea. 



cancellata, Say. I^otosiensis, Lea. 



carinocostata, Lea. S2'>incih's, Lea. 



catenaria, Say. forfa, Lea. 



" Melania, Lamarck. 

 Subgen. Melasiia, H. & A. Adams (i, p. 300.*) 

 Shell solid ; spire elevated, whorls smooth, longitudinally 

 plicate ; aperture i)roduced anteriorly ; inner lip simple, thin ; 

 outer lip acute, simple. 



blanda, Lea. DesJiayesiana, Lea. 



brevisjyira, Anthony. Edgariana, Lea. 



davceformis, Lea. laqueata, Say. 



Comma, Conr. Lecontlana, Lea. 



concinna, Lea. nitens, Lea. 



costulata, Lea. plicatida, Lea. 



crebricostata, Lea» plkifera, Lea. 

 Ciirreyana, Lea. 



" Genus Hemisikus, Swainson (i, 302.) 



Shell subulate ; whorls smooth, simple, numerous ; aperture 

 ovate, anteriorly contracted, canaliculate and emarginate in 

 front ; outer lip thin, crenulated at the edge. 



Syn. Tania, Gray, Basistoma, Lea. 



Ex. H. Uaeolatas, Wood, t. 32, f. 2, a, b. 



This genus comprises many fine species of fresh-water shells, 

 principally from South America, though a few have been re- 

 garded as inhabitants of other countries. 



bulbosus, Gould, symmetricus, Conr. lineolatus, Wood.f 

 " Genus Vibex, Oken (i, 303.) 



Shell turreted ; whorls tuberculated, spirally ridged or mnri- 

 cate ; aperture subcircular, produced, and broadly channelled 

 in front ; outer lip thin, simple. 



Syn. Claviger, Hald., 3Ielania, Swains., not Lamarck. 



" Subgenus Juga, H. & A. Adams (i, 304.) 

 Shell thin ; whorls rounded, transversely Urate or furnished 

 with elevated transverse lines ; aperture produced anteriorly ; 

 outer lip simple, acute. 



*This genus = the plicate species of Goniohams. M. brevispira, 

 however, is never plicate, althou.irli. included with the species. 



tTlie first two enumerated do not belons; to this i^enus, nor have 

 they the slightest alliuity with any of its species.— G. W. T., Jr. 



