142 DACTYLINiE. 



Genus agaronia, Gray. 



Foot long and pointed behind, shield with the side- 

 lobes moderate, acute. 



Operculum distinct. 



Shell oliviform, thin ; spire acuminate, suture chan- 

 nelled ; aperture wide, effuse anteriorly ; columella not 

 thickened posteriorly, tumid, with a few oblique plaits in 

 front. 



Syn. Hiatula, Swains. 



Ex. A. megalostoma, MeuscJien, pi. 15, fig. 3. Shell, 

 A. megalostoma, fig. 3, a. 



The animal of Agaronia differs from that of Dactylus 

 in having an operculum, and from that of Olivella. in the 

 form of the side-lobes of the foot ; the shell, moreover, is 

 light, the spire long and pointed, and the aperture wide 

 and effuse anteriorly. 



Species of Agaronia. 



cincta, .Reeve. Steerise, Reeve. 



contortuplicata, Reeve. striata, Swains. 



indusica, Reeve. testacea, Lam. 

 megalostoma, Meusch. 



Genus DACTYLUS, Klein. 



Tentacles enlarged at the base. Mantle with a poste- 

 rior filament lodged in the channelled suture of the 

 spire. Foot long and acuminate behind, shield with the 

 side-lobes tapering, acute, small. 



Operculum none. 



