CLAVATULINiE. 93 



Genus LACHE8IS, Risso. 



Shell strong, turreted, many-whorled, the last whorl not 

 very large ; surface crossed by longitudinal ribs and trans- 

 verse striae ; apex of spire mammillated ; aperture oval ; 

 canal very short, straight, not recurved ; outer lip slightly 

 thickened externally, crenated internally, 



Syn. Nessea, Risso. ? Anna, Risso. 



Ex. L. minima, Montagu, pi. 10, fig. 4. 



In this genus the animal is said by Philippi to have con- 

 verging tentacles, a short siphon, and a short ovate foot. 

 The operculum is entire and unguiform ; the apex of the 

 spire is mammillated, and there is no sinus in the outer 

 lip. 



Species of Lachesis. 

 candidissima, G. B. Adanis. minima, Montagu. 



Sub-fam. CLAVATULTN^. 



Operculum semi-ovate, nucleus in the centre of the 

 straight front edge. 



Genus CLAVATULA, Lamarck. 



Shell turreted, subfusiform ; spire elevated, whorls coro- 

 nated ; aperture oval ; canal moderate ; columella Bmooth ; 

 outer lip with a marginal notch below its union with the 

 body-whorl, and with a sinus near the canal anteriorly. 



Syn. Clavicantha, Stcains. 



Ex. C. imperialis, Lamarcl; pi. 10, fig. 5. Operculum, 

 C. bimarginata, Lamarck., fig. 5, a. 



