CYMBA. Brod. (_Cymba_, a boat or skiff.) _Fam._ Columellaria, Lam.--_Descr._ Smooth, ventricose, with a very short, mammillated, rude spire; and a very large, wide aperture, terminated anteriorly in a deep emargination; posteriorly in a flat ledge, which separates the outer lip from the body whorl; columella with three or four oblique, laminar, projecting folds, terminating in a point; outer lip thin, with its edge sharp; epidermis smooth, brown, covered partly or entirely by the glassy enamel, which, commencing with the outer lip, spreads over the body of the shell.--_Obs._ These very elegant shells, found in Africa, are distinguished from the true Volutes by the shapeless, mammillated apex of the short spire, by the large size of the aperture, and by the horizontal ledge which separates the outer lip from the body whorl. The genus Melo, also separated by Mr. Broderip from the Volutes, agrees with Cymba in some respects, but differs in the regularity of the spire. Fig. 434, C. Porcina. CYMBIOLA. Sw. The generic name for a group of Volutes, described as "armed with spinous tubercules, sometimes smooth, but never ribbed; spiral whorls gradually diminishing in size, but not distorted; apex thick and obtuse; pillar with four plaits." Mr. Swainson remarks that this genus is chiefly distinguished by the obtuse, but not irregular spire. The typical species are stated to be V. Rutila and V. Vespertilio, fig. 433. Tropical. CYMBULIA. (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 similarity to the shelly or glassy covering of other Pteropods, to which, although membranaceous, it is evidently analogous. The Cymbuliæ are found in the Mediterranean.