80 TRACHELIPODA. 



Genus 42.— TROCHUS.— Zmn«Ms. 



Generic Character. — Shell conical ; spire elevated, sometimes 

 abbreviated ; aperture transversely depressed ; margin of outer 

 lip disunited from the body at the upper part; columella arcu- 

 ated, more or less oblique at the base ; aperture provided with 

 a horny operculum. 



Trochus Zizyphinus.— The Muddy-Red Trochus. Plate 

 XII. fig. 2. With strong transverse stricB ; colour livid, with 

 undulated streaks of reddish flesh-colour, or brownish carnation. 

 One inch long. Inhabits the European seas. 



Genus 43 — ROTEhL A.— Lamarch. 



Generic Character. — Shell orbicular, glossy, destitute of epi- 

 dermis ; spire short, subconic ; lower parts convex and callous ; 

 aperture half round. 



Rotella vesirarius. — The Kindred Rotella. Plate XII. 

 fig. 18. Pale skin-coloured, or citron-coloured, the upper part of 

 body and spire spotted with dark brown. Half an inch long. 

 Inhabits the Indian ocean. 



GewMS 44.— SOLARIUM. -Zamarc^. 



Generic Character.— 'SheW orbicular, in the form of a de- 

 pressed cone ; largely umbilicated ; internal margins of the vo- 

 lutions, which are visible in the umbilicus, crenulated ; aperture 

 wide; mouth quadrangular, destitute of a columella. 



Solarium perspectivum. — The Perspective Solarium. Plate 

 XII. fig. 23. Cream-yellow, with brown or chestnut, and white 

 bands on the sutures of the volutions ; umbilicus ample, and 

 crenulated. Two and a half inches broad. Inhabits the Indian 



FAMILY II. SCALARIDES. 



Shell devoid of plaits or folds on the columella ; margins of 

 the aperture united in a circular form. 



