« Shell elongated, oval, oblique, considerably inflated ; beaks small ; with numerous, flat, narrow ribs, crossed by indistinct lines of growth ; colour pale flesh, or reddish-buff, covered by an olive or yellowish-brown epidermis ; inside glossy, white, flesh-coloured, or pale lilac, crenulated at the margins, with the ribs extending nearly half way from the base. […] This shell will be easily distinguished from the C. laevigatum, by its more lengthened form ; being more oblique, considerably more inflated, and in the ribs more numerous. »