18 PROCEEDINGS OF THE MALACOLOGICAL SOCIETY. 



Gwatkin collection labelled Minolia fall in this group, and so 

 do some tropical species labelled Solariella, but there are excep- 

 tions which, it is hoped, may form the subject of future research. 



3. Examination of three species of Olivella gives interesting 

 results. 0. nympha, Adams & Angas (Fig. 6), has a radula 

 with multicuspid rhachidian, which appears to be the normal form 

 in Olivella. 



0. pardalis, Adams & Angas, and 0. hrazieri, Angas, however, 

 have a tricuspid rhachidian, similar to that of Oliva but with a minute 

 additional cusp outside each of the lateral cusps. These minute 

 cusps are well marked in hrazieri (Fig. 7), but very small and 

 apparently sometimes missing in pardalis. A Gwatkin specimen of 

 hrazieri from Tasmania agrees with the Twofold Bay specimens. 

 All three species are operculate. 



I propose for these southern species with tricuspid rhachidians 

 the genus : — 



Belloliva 

 (a name suggested by Mr. Iredale) type species hrazieri, Angas. 



4. The radula of Microvoluta austrqlis, Angas, has affinities with 

 those of some of the Volutidce. It consists of a very long ribbon of 

 single unicuspid teeth with deeply indented base and long, sharp- 

 pointed cusp. (Fig. 8.) Evidently, therefore, this species is rightly 

 placed in the Volutidce, although the shell has suggested an affinity 

 with the MitridcB. 



