COLUMBELLA. Auct. (Columba, a dove.) _Fam._ Columellata, Lam.--_Descr._ Thick, oval, or angular; with short spire, and long narrow aperture, contracted in the centre, and terminating in a short canal; outer lip thickened and dentated; inner lip irregularly crenated. Epidermis thin, brown. Operculum very small, horny.--_Obs._ Those species of Mitra, which resemble Columbella in shape, may easily be distinguished by the plaits on the columella. The Columbellæ are marine, and few fossil species are known. Fig. 430, C. Mercatoria. Swainson has divided this genus into the following: _Columbella_, consisting of C. Mercatoria, &c.; _Pusiostoma_, consisting of the Strombiform species; _Crassispira_, which is most probably a Cerithium; _Nitidella_, consisting of the smooth species; _Conidea_, consisting of the more conical species; another set of the more conical species has been removed from this family, and placed in that of the "Coninæ," but as they are separated by no essential character, we suppose this has merely been done for the purpose of completing the "circle" of the last mentioned family, which otherwise would not have reached the required number of five. Mediterranean, East and West Indies, South America, Coast of California, Gallapagos, &c. COLUMELLA. A solid column formed by the inner sides of the volutions of a spiral univalve. It is sometimes described as the inner lip of the aperture, of which it forms a part; but the term would be more properly confined to that portion of the inner lip which is seen below the body whorl, over which the remainder of the lip is frequently spread. All the inner edge of the aperture, including that part of it which covers the body whorl, is called the columellar lip. In fig. 431, the anterior termination of the columella is indicated by the letter c. The axis, is an imaginary line drawn strictly through the centre of the whorls, whether their inner edges form a solid column or not. COLUMELLAR LIP. The inner lip. See COLUMELLA. COLUMELLATA. Lam. A family of the order Trachelipoda, Lam. containing the following genera:-- 1. MITRA. Elongated; aperture narrow; strong folds on the columella; including _Mitrella_, _Mitreola_, _Tiara_, and _Conohelix_. Fig. 431, 432. 2. MARGINELLA. Outer lip reflected; including _Volutella_, _Persicula_, _Gibberula_, and _Glabella_. Fig. 437. 3. COLUMBELLA. Outer and inner lips denticulated or granulated. Fig. 430. 4. VOLUTA. Outer lip thickened; folds on the columella; aperture generally wide; apex papillary; including _Scaphella_, _Harpula_, _Volutilithes_, _Cymbiola_. Fig. 433, 436. 5. MELO. Shell comparatively light; spire short, sometimes hidden; apex round, spiral; folds on the columella laminar. Fig. 435.