CONCHOLOGY. 137 



ill front, where its eilgo presents a transverse furrow; head small, 

 distinct, with two long, very sharp tentacula, the eyes at the ex- 

 ternal part of their base ; mouth provided with a trunk. 



Shell. Smooth, polished, oval-oblong, a little conical, with a 

 short mammelonated spire ; aperture somewhat narrow, slightly 

 oval on account of a light curve of the right edge which is dilated 

 outwardly ; the columellar edge marked with three oblique dis- 

 tinct folds. Inhabits the Indian Ocean. Twenty-four living 

 species and nine fossil, according to Defrance. 



Marginella radiata. Marginella nubeculata. 



M. limbata. M. aurantia. 



M. lifasciata. M. longivaricosa. 



M. dentifera. M. eburnea. 



M. bullata. M. persicula. 



M. avellana. M. tessellata. 



M. glabrella. M. cserulescens. 



M. quinqueplicata. M. bivaricosa. 



M. rosea. M. muscaria. 



M. faba. M. formicula. 



M. dactylus. M. lineata. 



M. cornea, M. interrupta. 



5. Genus Volvavia. PI. XII. 

 Animal. As above. 



Shell. Cylindrical, convolute ; spire obsolete or concealed > 

 aperture narrow, extending the whole length of the shell, with 

 one or more folds on the lower portion of the columella. Inhabits 

 the Indian Ocean. Five species. 



Volvaria pallida. Volvaria triticea. 



V. nionilis. V. oryza. 



V. miliacea. 



FAMILY XXI. 



CoxvoLUTA. Six genera. 



1. Genus Cypram. PI. XII. 



Animal. Oval, elongated, involute ; head provided with two 



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