TURBO. TURBAX. 191 



Shell conic, pointed : spires six or seven, hardly raised 

 or rounded, but defined by a raised beaded rib, and each 

 volution surrounded by four or five lesser beaded lines ; 

 the base regularly and distinctly striate circularly : color 

 grey, brownish, or white ; the larger ridges often red, and 

 spotted with white, and the tip generally of a fine deep 

 crilnson : aperture nearly square, not perlaceous within, 

 with sometimes a small indenture behind the pillar, like 

 an incipient perforation : diameter a quarter of an inch ; 

 height three-eighths. 



Western coasts, and Dublin bay. v. v. 



11. Trochus erythroleucos. Streaked Top-shelL 



Lister, pi. 616. f. 2 Dorset Cat. pi. 18. f. 2. 



Trochus conicus. Donovan, pi. 155. f. 1. 



Shell pyramidal, pointed, with a broad base which is 

 mostly surrounded by a raised rib : spires seven or eight, 

 hardly distinguishable by any raised line, each marked with 

 seven or eight fine circular and slightly beaded lines ; the 

 base rather convex, and circularly striate : color white, 

 grey, or dull reddish-brown, with often purple longitudinal 

 interrupted lines or streaks : aperture nearly square, per- 

 laceous within : diameter a quarter of an inch ; height 

 nearly half an inch. 



It is distinguished from the last, by its broad and cari- 

 nated base, the want of the crimson tip, the superior num- 

 ber and fineness of the circular lines on the volutions, in 

 being perlaceous within the aperture, and in not being so 

 strongly defined at the junctures by the beaded margin. 



Western coasts, and Dublin bay : rare. v. m. 



TURBO. TURBAN. 



Shell with a single valve, spiral, solid : aperture 

 contracted, more or less orbicular and entire. 



In the first division of this family it will be observed, 

 that we have collected into one point all those shells which 

 have the pillar-lip flattened, and are so peculiarly marked 

 by the groove and terminal perforation, arid which have 

 hitherto been scattered among the Turbo, Helix, and Ne- 



rita 



