74 CLASS GASTEROPODA. 
Bruguiéres has divided them into four genera, of Buccinwm, 
Purpura, Cassis, and Terebra, part of which have been again 
subdivided by Messrs. de Lamarck and Montfort. 
BuccinuMm, Brug., 
Includes the. emarginated shells without any canal, whose 
general form, as well as that of the aperture, is oval. ‘The 
animals, all such as are known, are deprived of the veil on the 
head, but are furnished with a proboscis, two separated ten- 
tacula, on the external side of which are the eyes, and a horny 
operculum. ‘Their siphon extends out of the shell. 
The name of Buccinwm is especially applied by M. de 
Lamarck to those in which the columella is convex and 
naked, and the margin without folds or rim. ‘Their foot is 
moderate, their proboscis long and thick, and their penis fre- 
quently excessively large. (Buecinum undulatum, L., List. 
662. 14, &c.) 
NAssa, Lam. 
The side of the columella is covered by a more or less broad 
and thick plate, and the emargination is deep, but without a 
canal. The animal resembles a true buccinum, and there are 
gradual transitions among the shells from one subgenus to the 
other. (Buccinum arcularia, List. 970, 24, 25, &c.) 
EBuRNA, Lam. 
Those which to a smooth shell, without a folded margin, 
add a widely and deeply-umbilicated columella. The general 
form of the shell is closely allied to that of the Olive. Their 
animal is unknown. (Buccinum glabratum, List. 974. 29. &c.) 
ANCILLARIA, Lam. 
The same smooth shell, and at the lower part of the colu- 
mella a marked lip. There is no umbilicus, neither is the spire 
