108 GENUS XXllI. VOLVTA. 



it (p/. 10. /. 1 and 2) ; the head is very broad ; at the under 

 side it has a long cylindrical trunk, with the mouth at the ex- 

 tremity ; the breathing tube short, projecting- nearly the length 

 of the head, with two small triangular flat horns, and the eyes 

 jjlaced on the head a little behind them (jpl. 10. /. 2) ; it has 

 no operculum. 



Lamarck has divided this genus into nine, as follow : 

 Oliva. Shell subcylindrical, hollowed at the base ; the whorls 

 of tlie spire separated by a channel ; pillar obliquely 

 striated (see Voluta porphyria, f, (58). 

 Ancilla. Shell oblong ; the spire short, not channelled ; the 

 base of the aperture slightly hollowed and efHise ; a thick 

 oblique swelling at the base of the pillar (see Voluta 

 Oliva, f. 69). 

 Voluta. Shell oval, more or less ventricose ; the spire obtuse, 

 like a nipple ; the base hollowed, without a canal ; the 

 pillar with folds, of which the inferior are largest and 

 longest (see Voluta musica, f. 70). 

 MiTRA. Shell turrited or sub fusiform, with a pointed spire; 

 the base hollowed without a canal ; the pillar with folds, 

 the inferior ones of which are the smallest (see Voluta 

 papalis, /. 7 1). 

 CoLUMBELLA. Shell oval, with a short spire ; the base of 

 the aperture more or less hollowed, without a canal, 

 having a swelling on the internal part of the right lip, 

 and folds or teeth on the pillar (see Voluta mercatoria. 



