94 TRACHELIPODA. 



vaulted scales, in spiral rows; also with strong waved spiral 

 striae; brownish-red, variegated with white. Two inches 

 long. Inhabits the Indian seas. 



Genus 46. — SCALARIA. — Lamarck. 



Generic Character. — Shell subturreted, with longitudinal, 

 elevated, thin, interrupted ribs; aperture rounded; margins 

 united in a circle, and edged by a reflected ridge. 



Scalaria pretiosa. — The AVentletrap, or Precious 

 ScALARiA. Plate XII. fig. 20. Conical, smooth, cream- 

 yellow; volutions disjoined, connected by longitudinal ribs; 

 body extremely ventricose ; a deep umbilicus. One and a 

 half inch long. Inhabits the Indian ocean. 



Genus 47.— VERMETUS.— ZawmrcA. 



Generic Character. — Shell thin, tubular, loosely spiral in 

 the lower part, the three or four upper volutions regularly 

 spiral; attached to other substances by the apex of the 

 spire; aperture orbicular, margins united, and provided with 

 an operculum. 



These shells are remarkable on account of their adheiing or being 

 aflSxed to marine bodies by the attenuated and pointed extremity of 

 the spire. 



Vermetus lumhricalis. — The Worm -like Vermetus. 

 Plate XII. fig. 24. Variously twisted ; reddish-brown, 

 sometimes clouded with darker brown. Two to four inches 

 long. Inhabits the African seas. 



FAMILY III. PLICACEA. 



Shell with the aperture somewhat contracted, and the 

 columella plaited. 



GenMs48.— PYRAMIDELLA Lamarck. 



Generic Character. — Shell turreted, destitute of epider- 

 mis ; aperture entire, semi-ovate, the outer lip with a sharp 



