MANUAL OF THE MOLLUSCA. 



Proserpinella, Bland, 1865. 



Etymology diminutive of Proserpina. 

 Type^ P. Berendti, Bland. 

 Disfrihution, Mexico, 3000 to 4,000 feet. 

 Shell as in Proserpina ; columella fold absent ; aperture witt 

 one parietal lamelliform plait. 



[Family HELicnoD^j 

 Contains : — 



Helicina [Lucidella, Trochatella, Alcadia). 



Schasicheila. Shell with very close, long, spiral, epidermal 

 fringes. Distrihution, 5 species. Central America and the 

 Bahamas. 



Perenna, Guppy, 1867 ; P. lamellosa, Guppy, Trinidad. Shell 

 ''ike Helicina, depressed ; whorls lirate and carinate. Operculum 

 thin, suboyal, concentrically striated; nucleus subcentral. 

 Animal like Helicina. Distribution, 2 species. Trinidad, 

 Yucatan. 



BoTJHcrERA, Pfeiffer, 1851. 



Type, B. helicinseformis, Pf. 



Shell like Helicina, dull, and without the columellar callosity ; 

 columella toothed beneath ; aperture ovate ; peristome spread- 

 ing. Lingual dentition agrees with that of Helicina. Oper- 

 culum ovate, horny, few-whorled. 



Distribution, 2 species. South America. 



Stoastoma, and 



Georissa, Blanford, 1864. 



Ty2:)e, Hydrocena pyxis, Benson. 



Animal furnished with hemispherical lobes in the place of 

 tentacles ; eyes normal ; foot short, rotund. Operculum semi- 

 oval, no spiral structure as in Helicina ; excentrically striated, 

 testaceous, transparent. 



Shell resembling that of Hydrocena, imiperforated, small, 

 nonical, amber-, or reddish-coloured, spirally sulcated or striated. 



Distribution, 6 species. Adhering to limestone rocks, India. 



[Family Aciculld^.] 



The genera enumerated in this family are : — Acicula, Geo- 

 T.rsLAXiA, Chittya, and Truncatella, the last with the foUow- 



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