160 



and widest at the lower part. Recent and fossil. 

 PI. iii. fig. 25. 



24. Terebellum. A spiral and convoluted univalve, with 

 a pointed apex; the opening long and narrow upwards, 

 toothless, and notched at the base. Recent and fossil. 

 PL iii. fig. 26. 



M. de Montfort has separated a shell which had been 

 included in the genus terebellum, and has formed of it the 

 following genus, since adopted by Mr. Sowerby. 



25. Seraphs. A convoluted, elongated, univalved shell; 

 spire internal, concealed; base truncated; mouth longi- 

 tudinal, extending to the apex of the spire ; lip sharp ; co- 

 lumella smooth. It differs from terebellum chiefly in having 

 its spire entirely internal. 



26. Volvaria. A cylindrical and convoluted univalve ; 

 the spire scarcely extruded ; the opening narrow, the length 

 of the shell; the columella plaited at its base. Recent. 

 PI. iv. fig. 1. 



27. Oliva. A spiral and nearly cylindrical univalve, 

 notched at the base ; the turns of the spire separated by a 

 small groove ; the columella obliquely plaited. Recent and 

 fossil. PI. iv. fig. 2. 



28. Ancilla. An oblong, subcylindrical univalve, with 

 a short spire ; the sutures not grooved ; the aperture spread; 

 the base notched ; a thick oblique fold at the base of the 

 columella. Recent and fossil. PI. iv. fig. 3. 



29. Valuta. A subfusiform, more or less tumid, uni- 

 valve ; apex obtuse or papillated ; base slightly grooved, not 

 channelled : columella plaited, the lower plaits being the 

 largest or the longest. Recent and fossil. PI. iv. fig. 4. 



30. Mitra. A subfusiform univalve, with a pointed apex ; 

 base notched, but with no channel ; the columella plaited, 

 the lower plaits being the smallest. Recent and fossil. 

 PI. iv. fig. 5. 



31. Columbella. An oval univalve, with a short spire; 



