364 littorinid^:. 



nacreous deposit of carbonate of lime natural to the 

 shell/' The tongue is remarkably long and slender in 

 proportion to the size of the body — more than three 

 times its length. The operculum, resting on a ledge, is 

 never sunk within the shell. 



It is the Turbo petr&us of Montagu, T. carulescens of 

 Lamarck, L. Basterotii of Payraudeau, Helix neritoidea 

 and T. Lemani of Delle Chiaje, T. petreus of Fleming, 

 L. melanostoma of Krynicki, and T. petricola of Leach. 



3. L. ru'dis*, Maton. 



Turbo rudis, Maton, Nat. Hist, and Antiq. West. Count, i. p. 277. L. 

 rudis, F. & H. iii. p. 32, pi. lsxxiii. f. 1-7, & lxxxvi. f. 1. 



Body of various hues, white, yellow, brown, or fleshcolour, 

 usually more or less clouded or streaked across with dark 

 purple : head thick, wrinkled transversely, often tinged with 

 violet on the upper part and neck : tentacles rather slender, 

 with blunt tips, frequently marked with a pale-yellowish or 

 black stripe in front down the middle, and with another of a 

 similar colour on the under side : eyes globular and prominent, 

 on short and thick stalks, which are amalgamated with the 

 tentacles at their outer bases ; pupils black, within gelatinous 

 and transparent irides : foot double-edged in front ; sole light- 

 yellow or whitish, bordered by a clear hem at the sides and 

 behind, and divided down the middle by a slight fold. 



Shell forming a short cone, solid, opaque, and lustreless : 

 sculpture, several flattened spiral ribs, crossed obliquely by 

 slight, irregular and laminar marks of growth ; the surface is 

 covered with close-set minute spiral wavy striae or wrinkles, 

 which are always discernible in every form of this extremely 

 variable species : colour most diversified, consisting chiefly of 

 yellow, brown, red, orange, and purple, sometimes jet-black 

 or pure white, and usually variegated by zones or spiral bands 

 of different hues and widths : epidermis not observable, and (if 

 formed) probably a mere film and caducous : spire moderately 

 pointed : whorls 6-9, convex, somewhat flattened or compressed 

 just below the suture; the last whorl occupies in the female 



* Rough. 



