258 CLASS III. GASTEROPODA. ORDER VII. PECTINIBRANCHIATA. 
under the above title (‘‘ Les Enroules”’). It stands, however, as a family 
upon rather an artificial basis ; the only distinctive character of the Con- 
voluta is in the whorls of the shell being closely convoluted over each 
other without descending, so that the upper or sutural portion of them 
remains on a plane with the spire ; and it is not without considerable 
reluctance that we follow the arrangement of our venerable predecessor. 
We feel our difficulty the more from having had occasion to remove two 
genera, Oliva and Ancillaria, to the family of the Purpurifera, on account 
of their affinity with the Eburne, whilst their shells exhibit the same dis- 
position of growth which has been selected for the determination of this fa- 
mily ; there is a difference of organization, too, between certain of the Con- 
voluta, which seems scarcely to admit of their association. The Cypree 
have an unusually large mantle, which dividing into two unequal lobes 
entirely envelops the shell ;. the calcifying organ of the Coni, on the con- 
trary, is comparatively small, and the hinder extremity of the foot is fur- 
nished with a minute operculum. The situation which should be assigned 
to the last of these genera has severely taxed the ingenuity of concholo- 
gists: Deshayes refers it to his family of the Buccinide ; Gray to his fa- 
mily of the Muricide ; whilst De Blainville includes it immediately after 
Strombus, in his family of the Angyostomata. The Coni have evidently 
few characters in common with the Cypre@, and we shall no doubt be 
censured by many for our rigid adherence to an arrangement which is 
evidently at fault. It must be pleaded, however, that the anatomy and 
affinities of these mollusks are not yet sufficiently understood to induce us 
to hazard a removal. 
We include five genera in this family : 
Erato. TEREBELLUM. 
CypR@a. Conus. 
OvuLuoM. 
