Shell smooth, not covered with epidermis, conical, elongated or sub-turriculated; aperture semi-oval, entire; the outer lip sharp, dentated interiorly, plaited, enlarged over the umbilicus, which it leaves more or less exposed. Pyramidella terebellum. P. dolabrata. P. plicata. P. corrugata. P. maculosa. _P. dolabrata._ The dentated Pyramidella. Pl. 22, fig. 5. Answers to the above description; when placed on its base, it falls on one side. _P. terebellum._ The wimble Pyramidella. Smooth, glossy, white, with reddish-brown bands; columella recurved; inside of the lip smooth. FAMILY XIV. SCALARIDES. Three genera. 1. Vermetus. One species. Resembling in appearance the shell of a Serpula; but the organization of the animal caused this to be made a distinct genus. Its shells are usually found grouped together or intertwined with each other, and are very remarkable for being attached to marine bodies by the attenuated and pointed extremity of the spire. Shell conical, tubular, thin, involute spirally, more or less close, with whorls almost completely disunited; free or adherent by intertwining; aperture straight, circular, with edges sharp and complete; several partitions not perforated towards the summit; operculum horny and complete. _V. lumbricales._ The wormlike Vermetus. Pl. 23, fig. 3. A flexuous shell, with a spiral, acute tip, very much resembling a corkscrew; colour reddish brown, sometimes clouded with a darker shade. 2. Scalaria. Seven species. A marine shell, with a circular aperture like the Cyclostoma, but easily distinguished by its turreted form; longitudinal, elevated ribs, never connected together, rather oblique, and sharp; the shape of the shell is elegant, being a spiral cone, formed by gibbous whorls, unconnected by a columella, gradually increasing from the apex to the base. The colour is generally yellowish or brownish white. When perfect and of good size, they are of great value and highly prized. Shell sub-turreted, the whorls of the spire more or less pressed and garnished with interrupted longitudinal ribs, formed by the successive preservation of the reflected margin of the aperture, which is small, perfectly round, with edges united, thickened, and outwardly reflected; operculum horny and thin. Scalaria pretiosa. S. lamellosa. S. coronata. S. varicosa. S. communis. S. Australis. S. raricosta. _S. pretiosa._ The precious Scalaria, more commonly called the Wentle Trap, or Winding Staircase. Pl. 23, fig. 1.