Part 25

CLITIA. Leach. Fam. Balanidea, Bl. Order, Sessile Cirripedes, Lam.--Descr. Sub-conical, compressed, consisting of four unequal valves, two larger and two smaller, joined together side by side, by the interlocking of their dentated edges, a process somewhat like that which joiners call dove-tailing. Operculum, consisting of two unequal pointed valves.--Obs. Clitia is known from Creusia, by the articulations of the valves, and by the operculum, which in Creusia consists of four valves. Fig. 20. C. Verruca, (Lepas Verruca, Gmelin.) Britain and Peru.

CLOSE. The margins of a bivalve shell are described as being close, when there is no hiatus between them in any part, otherwise they are described as gaping.

CLOTHO. Faujas. Fam. Conchacea, Bl. More properly belonging to the Pyloridea, Bl.; and the Lithophagidæ, Lam.--Descr. "Oval, nearly regular, longitudinally striated, equivalve, sub-equilateral; hinge consisting of a bifid tooth, curved like a crochet, larger in one valve than in the other." This description is translated from Blainville, who states that he has never seen the shell. Annales du Museum D'Histoire Naturelle, tom. 9, pl. 17, fig. 4-6.

CLYPEIFORM. (Clypeus, a shield.) Open, flat, shaped like a shield or buckler, as Umbrella, fig. 233, and Parmophorus, fig. 242.

CLYPIDELLA. Sw. A sub-genus of Fissurella, described as having one extremity of the shell slightly raised. C. pustula. Sow. Gen. fig. 3.

COAT OF MAIL. A common name given to shells of the genus Chiton, on account of their resemblance to jointed armour.

COBRESIA. Hübner. VITRINA, Auct.

COCHLIATE. (Cochleare, a spoon). Applied to any shell or part which is hollow and oval, as Patellæ, &c. The cavity containing the cartilage in Mya, fig. 71, is Cochleate.

COCHLICELLA. One of the sub-genera into which De Ferrusac has divided the genus Helix, consisting of Bulinus decollatus, fig. 279, and similar species. See Helix.

COCHLICOPA. Fer. A sub-genus of Helix, partly corresponding with Polyphemus of De Montfort, and consisting of species of Achatina, which have the outer lip undulated.

COCHLITOMA. Fer. A sub-genus of Helix, corresponding with the genus Achatina, Auct. not including those with undulated outer lips.

COCHLODINA. Fer. A sub-genus of Helix, including the genus Clausilia, Auct.

COCHLODONTA. Fer. A sub-genus of Helix, containing Pupa Uva, Auct. &c.

COCHLOGENA. Fer. A sub-genus of Helix, containing pupiform shells, such as Azeca tridens, fig. 290.

COCHLOHYDRA. Fer. A sub-genus of Helix, composed of the genus Succinea, Auct.

COCHLOSTYLA. Fer. A sub-genus of Helix, composed of the genus Bulinus, Auct.

COLIMACEA. Lam. This Family, of the order Trachelipoda, Lam. includes all land shells, which might with propriety be divided into three sections, the first of which contain the following well-known genera:--

1. SUCCINEA. Oval, transparent, oblique; animal amphibious. Fig. 265, 266.

2. HELIX. The type of which is the common snail shell. The separation of Carocolla, on account of the angulated whorls, or that of Geotrochus, on account of the turbinated shape, cannot be well maintained. Fig. 264, 267, 268, 273 to 276, 278 to 281, 294.

3. ANOSTOMA. The aperture turned up towards the spire. Fig. 271, 272.

4. STREPTAXIS. Whorls excentric. Fig. 269, 270.

5. BULINUS. Oval; aperture entire, including Bulimulus, Balea, Cionella, Azeca. Fig. 282 to 285, 289, 290, 296.

6. ACHATINA. A notch terminating the columella. Fig. 286 to 288.

7. PUPA. Cylindrical; including Vertigo, Alæa, &c. Fig. 291 to 293.

8. CLAUSILIA. Cylindrical, with a clausium. Fig. 295.

Obs. The above are united in the system of De Ferrusac under the generic name Helix, and divided into sub-genera as explained under that word.

The next section, included in the family Auriculacea, Bl., contains the genera Auricula, Chilina, Carychium, Marinula, Scarabæus, and Partula. Fig. 297 to 302.

The third section contains the following genera of land shells with opercula.