Cl'PR.'EA. 137 



tlie body whorl. Tlie genus Melo, also separated by Mr. Brode- 

 rip from the Volutes, agrees witb Cymba in some respects, but 

 differs in the regularity of tbe spire. PI. xx. fig. 434, C, Por- 

 cina. Nine species are enumerated in the Monograph by the 

 Author, pt. 8. Thes. Conchyliorum. 



CTMBIOLA. Swainson, 1840. The generic name for a group 

 of Volutes, described as " armed with spinous tubercules, some- 

 times smooth, but never ribbed ; spiral whorls gradually dimi- 

 nishing in size, but not distorted ; apex thick and obtuse ; pillar 

 with four plaits." Mr. Swainson remarks that this genus is 

 chiefly distiaguished by the obtuse, but not irregular spire. 

 The typical species are stated to be V. Eutila and V. Vesper- 

 tilio, fig. 433. Tropical. 



CTMBIUM. Adanson, Melo, Broderip. 



CYMBULIA. Peron and Leseur, 1810. (Dim. from Cymba.) 

 Fam. Pteropoda, Lam. An extremely light, cartilaginous 

 covering of a molluscous animal, so named from its similarity in 

 shape to a boat. We mention it here on account of its simi- 

 larity to the shelly or glassy covering of other Pteropods, to 

 which, although membranaceous, it is evidently analogous. The 

 Cymbulise are found in the Mediterranean. 



CYNODONTA. Schum. 1817. Scoltmus, part. Swainson, 

 Represented by our figure 382. 



CYPE^A. Liunseus. Fam. Enronlees, Lam. Angyostomata, 

 BL — Descr. Oval or oblong, ventricose, convolute, covered by an 

 enamel, generally smooth and shining. Spire short, nearly hid. 

 Aperture long, narrow, terminating in a short canal at both 

 extremities. Outer lip dentated, thickened inflected. Inner lip 

 dentated, thickened, reflected over part of the body whorl. — 06s, 

 These shells are so distinguished by the two rows of teeth ar- 

 ranged on each side of the aperture; the thickened front formed 

 by the inner and outer lips ; and the enamel deposited over the 

 back of the shell from the mantle of the animal which envelopes 

 it, that there is no danger of confounding them with any other 

 genus, except ia a yoimg state. Before they have arrived at the 

 full growth, the front is not thickened, and the outer lip is tliin. 



