either by name or description, says, it is so much like that 

 of a Buccinum, that " to make of the Sigaretiis a Buccinum, 

 it is only necessary that the whorls of the shell should be 

 less unequal, and should be elongated into a more acute 

 spire." The animal as delineated in his ])late, or that part 

 which is visible from above, consisting entirely of the ex- 

 panse of the thick, fleshy mantle, is oval and convex. On 

 the anterior margin, a little on the left, is a deep emargi- 

 nation, which is the extremity of an open canal beneath, 

 originating above the neck in the branchial cavity, to 

 which it conveys the water, and in which are two pectinat- 

 ed and vascular lamelliform branchiae. The shell is en- 

 tirely enclosed in the convexity of the mantle. The head 

 is formed as in Buccinum. The tentacula are conic, with 

 .the eyes at their base. The vent is posterior to the canal 

 and before the middle of the body. The foot much smal- 

 let than the mantle and also oval. The sexes are in sepa- 

 rate individuals. 



Blainville has formed a new genus under the name of 

 ,Cryptostoma, for one or two East Indian species, the shells 

 of which though more depressed, are altogether generi- 

 cally similar to Sigaretus, in which other naturalists place 

 them ; but the animal, agreeably to his description, differs 

 in having a more elongated form, appendiculated tentacu- 

 la and but one large branchial pec ten. 



FLATE XXV, 



