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Descriptions of new Genera and Species of Shells. By 

 Augustus A. Gould. 



Vertigo nacca. T. ovata, lucida, alabastrica, tenmssime striata ; 

 anfr. 4 -|- ventricosis ; apice obtuso ; sutiira profunda : apertura sub- 

 circularis dente palatali (interdum bifido) dente columellari, dente 

 basali denteque labiali armata; peritremate valde reflexo ; umbilico 

 rimato. Axis. Jg- ; diam. ^L poll- Hab. Hawaii. Dr. Newcomb. 



The denticles are similar to those in V. Gouldii and V. iantilla. The 

 latter is smaller, has a rugose surface, and one more denticle. 



Nassa plicatella. T. parva, elongata, ovato-conica, acuminata, 

 sublivida et fascia albida cincta, longitudinaliter confertim plicata et 

 striis volventibus plicas baud secantibus cincta; anfr. 7 planulatis; 

 sutura bene impressa et marginata : apertura angusta, elliptica, postice 

 acuta: labro simplici : sinu obliquo, vix reflexo. Axis 15; diam. 17 

 millim. Hab. British Burmah. Mr. Benjamin. 



Resembling somewhat N. achatina, though very much smaller. 



Chrysallida curtina. T. minuta, ovato-turrita, albida ; spirag 

 anfract. 6-7 convexis, seriebus granularum quatuor cancellatis, granulis 

 antice sensim defuentibus, anfr. ultimo dimidiam longitudinis testae 

 superante : apertura angusta, antice producta ; columella postice plica 

 munita. Long. 5 ; lat. 2 millim. Inhabits S. Carolina. 



It has the aperture, and in general the sculpture of Chemnitzia, 

 with the columellar fold of Odostomia. 



DuNKERiA suTURALis. T. minuta, eborea, turrita ; anfract. 7-8 

 convexis, longitudinaliter 10-12 plicatis (plicis antice e van esc entibus) 

 et striis volventibus tenuibus cinctis quorum una subsuturali bene 

 impressa ; anfract. ultimo dimidiam longitud. testte breviore : apertura 

 lunata, trientem longitud. testfe brevior. Long. 3 4- ; lat. 1 millim. 

 Hab. Fort Johnson, Charleston Harbor, S. C. 



This minute shell belongs to the Chemnitzise, with strongly marked 

 sculpture, and with ventricose whorls. 



RissoA iNCOMPTA. T. minima, elongata, vitrea, lactea postice 

 rubiginosa ; anfr. 7 rotundatis, costis ad tres cinctis, longitudinaliter 

 inordinatim clathratis et indentatis, posticis carinatis : apertura circu- 

 laris, peritremate simplici, incrassato. Long. 2 ; lat. 1 millim. Among 

 coral sand, Florida ; abundant. 



RissoA (s. g. Setia) patens. T. minuta, ovata, tenuis, vinosa,levis; 

 anfr. 5-6 ventricosis, linea subsuturali impressa ornatis: apertura 

 rotundata postice emarginata; columella parum reflexa ; labro sub- 

 incrassato, fusco. Axis 3 ; diam. 2 millim. Hab. Fort Johnson, Charles- 

 ton Harbor, S. C. 



This minute Rissoid is remarkable for its large aperture and subsu- 

 tural impressed line. 



