COLUMBELLA. 



Lam, — Systeme des Anim. sans vert. 



TESTA ovato-oblonga, epidermide induta; spird 

 breviuscula ; aperturd elon^ata^ basi emarginata ; 

 labio externo incrassato, median a parte intus tu- 

 mido^ vel subtumido^ denticulate ; interno ple- 

 rumque basi denticulate . ( Operculum minutis" 

 simum, corneum, exile. J 



The Voluta mercatoria of Linne^ may be regarded as the 

 type of this pretty little Genus, of which only a few species 

 are known; De Blainville, in the Dictionnaire des Sciences 

 Naturelles, (article Colomhelle^) says only two ; but we be- 

 lieve the number is extended to at least ten times as many. 



The general form of the shells of this genus is ovate- 

 oblong, some species are rather elongated, and others are 

 almost as broad as they are long, in proportion as the spire, 

 which is in general short, is either elongated or depressed. 

 The aperture is in most of the species more than half the 

 length of the shell, rather narrow and notched at the base, 

 scarcely produced into a very short canal. The outer lip 

 is thickened, the middle part of it is internally more or 

 less tumid ; and the tumid part denticulated more or less 

 strongly: sometimes, instead of the tumour, there are only 

 a few strong teeth. The central part of the inner lip, op- 

 posite to the internal tumour oi tlie outer, is generally 

 rather contracted, so that the internal edges of the aper- 

 ture are nearly parallel, and it appears rather sinuous : the 

 columella is mostly denticulate at the base. Lamarck and 

 Bruguiere inform us, that the animal inhabitant of this 

 shell is furnished with a very small, slender, horny opercu- 

 lum, probably on the authority ofAdanson: we have never 



