PROVISIONAL AID TO THE STUDY OF TASMANIAN MOLLTJSCA. 



(xiv.) Family Marginellid^e. 



Genus Marginella. Lam. 



3-96.) 



Shell smooth, bright ; spire short or concealed ; aperture 

 obtuse or truncated in front ; columella plaited ; outer 

 Up (of adult) with a thickened marginal varix; inner 

 margin smooth or crenulate. Bist.—- Tropical and 

 sub-tropical. 



Genus Erato. Eisso. (87.) 

 Shell obovate, polished ; spire short, conical, distinct ; aperture 

 linear ; outer lip without varix, but thickened towards 

 the middle, and denticulate within ; columella with 

 distinct plaits at the fore part. Bist. — World-wide. 



(xv.) Family Olivid*. 

 (Shells sub-cylindrical, porcellanous, brilliant in colour; 

 columella lip, sutures and spire more or less covered 

 with a callous deposit; outer lip simple, notched 

 below.) 



Genus Olivelxa. Swainson. (97.) 

 Shell small, polished, sub-cylindrical, solid ; spire produced, 

 acute ; suture canaliculate ; aperture narrow behind, 

 enlarged anteriorly; columella plicated in front, 

 callous posteriorly ; operculum present, thin, half ovate 

 with apical nucleus. Bist.— 1ST. America, China, Aus- 

 tralasia, etc. 



Genus Oliva. Brag. (98.) 

 Shell oblong, sub-cylindrical, polished ; spire short, conical ; 

 suture canaliculate ; aperture long, narrow, anteriorly 

 widely notched ; columella obliquely plicate ; sulcate 

 or striate in front; callous posteriorly; outer lip 

 simple ; operculm wanting. But. — America, Africa, 

 India, Polynesia, Australasia. 



Genus Anctllaria. (99-101.) 

 Shell oblong, polished, sub-cylindrical ; body whorly, swollen ; 

 sutures covered by enamel ; aperture broadly effusu 

 below ; columella not umbilicated, with a few oblique 

 anterior plaits ; basal whorl marked with revolving 

 grooves which _ terminate occasionally in a slight 

 anterior lip projection or tooth ; operculum generally 

 present, small, ovale, acute. Bist. — Eed Sea, Indian. 

 Ocean, Japan, West Indies, Australasia. 



