278 Transactions. — Zoology. 



jection being noticed in the outline near the columella. Aper- 

 ture angled behind, rounded in front, continuous, thin-edged, the 

 edge slightly expanded. Columella nearly vertical, interior trans- 

 parent. Operculum quite colourless and presenting a malleated 

 appearance on the internal surface. Since deciding upon de- 

 scribing these shells I have had no opportunity of obtaining the 

 animal alive. Height, 2J mm. ; breadth, 1 mm. 



Hab. Devonport. 



This shell is labelled R. annulata in the Auckland Museum, 

 but is not that species as named by Professor Hutton. 



Rissoia carnosa (= flesh-coloured), n. sp. Fig. 6. 



Shell thin, imperforate, flesh-brown, with a cream-coloured 

 band above the periphery, some specimens being a darker brown 

 without the band, others having the last whorl entirely cream- 

 coloured. Whorls 5J (of which two form the smooth dome- 

 shaped dark protoconch), slightly rounded, the body- whorl more 

 so, and having about twenty straight longitudinal ribs crossed by 

 about twenty-five spiral lirae, which diminish in strength as they 

 ascend to the apex, while the ribs are stronger on the upper 

 whorls and in some specimens die away on the body-whorl. 

 The shell is so thin that the sculpture is plainly visible when 

 looked at through the aperture. Suture well marked ; aperture 

 auriform, not thickened anywhere, not continuous. Animal and 

 operculum unknown. Height, 1\ mm. ; breadth, \ mm. 



Hab. Takapuna. 

 Type in my collection. 



Rissoia candidissima (= very white), n. sp. Fig. 7. 



Shell thin, imperforate, semitransparent-white when fresh. 

 Whorls 4|, of which two form the smooth elevated protoconch, 

 very round, with about twelve distant longitudinal ribs on the 

 body- whorl crossed by twelve spiral lirae. Suture deep, aperture 

 rounded but not continuous, slightly thickened. Animal and 

 operculum unknown. Height, 2 mm. ; breadth, 1 mm. 



Hab. Takapuna. 



Type in my collection. 



Rissoina (Eatoniella) limbata, Hutt. Fig. 8, a. 



I give a drawing of the radula x 600 and of the operculum of 

 this species, which was originally described by Professor Hutton 

 as a Cingvla (the animal being unknown), and then found its way 

 into Phasianella (see P. Mai. Soc, hi., p. 8). I also examined the 

 dentition and operculum of transparent-pink and pellucid-white 

 specimens, finding them the same as the type. 



