GASTEROPODA PECTINIBRANCHIATA. 
65 
tion and a semi-canal, which serve to conduct water into the bran- 
chial cavity, and which form the passage to the following family, but 
of which there are no impressions on the shell. The tentacula are 
conical, with the eyes at their external base : the penis of the male is 
very large. 
Some species are found on the coast of France. The 
CoRiocELLA, Blamv., 
Consists of Sigareti, the shell of which is horny, and almost mem- 
branous, like that of the Aplysiae* * * § . 
Cryptostoma, Blainv. 
The shell, resembling that of a Sigaretus, with the head and abdo- 
men, which it covers, supported by a foot four times its size, cut 
square behind, and forming before a fleshy, oblong bundle that con- 
stitutes nearly one half of its mass. The animal has a flat head, two 
tentacula, a broad branchial pecten on the roof of its dorsal cavity, and 
a penis under the right tentaculum ; but I can find no emargination 
in the inantlef. 
FAMILY in. 
BUCCINOIDA. 
This Family has a spiral shell, in the aperture of which, near the 
extremity of the columella, is an emargination Or a canal for transmit- 
ting the siphon or tube, which is itself but an elongated fold of the 
mantle. The greater or less length of the canal, when there is one, 
the size of the aperture, and the form of the columella, furnish 
the grounds of its division into genera, wliich may be variously 
grouped]; . 
Conus. Lin. § 
So called from the conical shape of the shell ; the spire, either per- 
fectly flat, or but slightly salient, forms the base of the cone, the 
apex being at the opposite extremity ; the aperture is narrow, recti- 
linear, or nearly so, extending from one end to the other without 
enlargement or fold, either on its edge or on the columella. The 
* The CoHocolle noire, Blainv. Malac., XLTI, f. 1 . This animal is not deprived 
of a shell, as the author of the genus imagined, hut it is thin and Ilexible. 
•f- Besides the species in the British Museum (CV. Leachii, Blainv. Malac., XLII, 
3), we have one (Cr. coroUnum, Cuv.) sent from Carolina hy L. L’llerminier. 
I They are the Par.irephalophora Dio'ica Siphonobranchiata of Blainville. 
§ M. de Blainville unites the Coni, Cypreee, Oculce, Terehella, and the Valuta, in a 
family which he calls Angyostoma. 
In placing here the genera v.'ith a straight aperture, we must not be understood as 
meaning to approximate them to the preceding family, but only to present them 
first, as possessing the most striking characters of all those which are furnished with 
a siphon. 
VOL. III. ^ 
