3!) 



In the ' Zoology to (.'apt. Beeehey's Voyage ' I divided the genu 

 into two, according to the structure of the animal, via. OUva and 

 Jgaronia, and observed that some OUva were furnished with an 

 operculum not present in other Bpecies. .Mine lately in the text to 

 Mrs. Gray's ' Figures of Molluscous Animals, ' and in the 'Guide to 

 the Collection of Mollusca' in the Museum, 1 have extended the 

 number of genera to four ; separating the operculated Oliva under 

 the name or o/irel/a, and giving to an animal figured by lyOrbignj 

 as Oliva auricularia the name of Scapkura. 



These shells sometimes have an elevated shelly croM band. La- 

 marck had a specimen of Oliva porphyria (IIi>t. \iii. 418) bo marked. 

 It is not uncommon in O. guttata, where it has heen regarded as a 

 species; but it is often found in other Bpecies. 



A further study of the figures of the animals given by authors has 

 induced me to revise this arrangement and propose the following 



Synopsis of the Genera. 



I. Head exposed ; tentacles elongate, subulate ; eyea distinct, tub- 

 basal. The foot elongate, dilated, front lobe semicircular; 

 opercula none. Shell with the front belt narrow. 



* Spire simple, with sutxiral groove open to the top. 



1. Strephona. 



Pillar lip simple, not covering the front belt ; inner lip cross- 

 grooved. 



2. ISPIDULA. 



Pillar lip simple, not covering the front belt ; inner lip thickened, 

 the whole length with two or three slight grooves in front. 



'.I. Ram ola. 



Pillar lip simple, not covering the front belt ; inner lip with a 

 series of transverse parallel grooves in front extending over the 

 pillar. 



4. Carmione. 



Pillar lip expanded so far back a< to cover the front belt, and with 

 an oblique raised ridge in front ; inner lip grooved. 



** Spire rations, obliterating the sntura' grooves, except "« the last 

 ivhorl. 



.'>. Clanxopbila. 



Shell ovate or obconic ; aperture wide. Pillar lip expanded. 

 Pillar twisted and grooved in front. Front belt broad. 



fi. ( i ULKOLA. 



Shell Bubcylindrical ; spire -mall; aperture linear. Pillar lip 

 Simple, defined j inner lip grooved. Front belt narrow. 



