COLIMACEA. 27 



-156; Fleming, Edin. Ency., VII, p. 74, pi. 203, f. 10; Tuvho 

 tumidus, Pennant, Brit. ZooL, IV, p. 128, pi. 82, f. 110; Turho 

 striatus, Da Costa, p. SQ, pi. 5, f. 9; Donovan, Brit. Sh., II, pi. 

 59; Nerita elegans, Miiller, Verm., II, p. 177. 



Shell tapering, oblong-ovate ; body large, tumid ; spire con- 

 sisting of four ventricose volutions, and ending in an obtuse 

 apex; whole external surface provided with numerous, close-set, 

 raised, spiral striae, crossed by finer longitudinal striae, producing 

 a reticulated appearance ; aperture round, with a slight angular 

 contraction above; outer lip thin, smooth on the edge, and con- 

 tinuous ; inner lip slightly reflected on the columella, with a 

 subumbilicus behind ; colour usually cinereous, with a purplish 

 tinge, and reddish-purple at the apex; frequently fasciated with 

 two rows of purplish-brown spots, or interrupted bands, or in 

 some instances longitudinally streaked with a similar colour ; 

 operculum horny externally, and testaceous on its inner surface, 

 with a single depressed spiral line, and a series of fine striae 

 radiating from it towards the circumference. Length five- 

 eighths of an inch ; breadth three-eighths. 



Found in the Limestone districts of England and Wales ; 

 and Portrush, Ireland. 



2. Cyclostoma marmorea, pi. IV, f. 13. 



Cyclostoma marmorea, Brown, Edin. Jour. Nat. and Geo. 

 Science, I, p. 12, pi. 1, f. 10, 11 ; lb., Illust. Conch., p. 34, pi. 

 18, f. 15. 



Shell oblong-ovate ; body large, inflated ; spire small, con- 

 sisting of four deeply divided volutions, abruptly tapering to 

 an obtuse apex ; aperture quite orbicular ; outer lip united all 

 round ; pillar lip slightly reflected on the columella, behind 

 which is a deep umbilicus ; whole surface smooth, glossy, of a 

 pale ash colour, covered with zig-zag markings of a reddish 

 chestnut-brown, which form four spiral fasciae on the lower 

 volution, and gradually become obsolete on the superior por- 

 tion of the spire. 



I noticed this elegant shell in the cabinet of my friend James 

 Gerard, Esq., Edinburgh, associated with some British speci- 

 mens of Cyclostoma elegans, to which it is closely allied in 

 form, but may at once be distinguished from that shell in being 

 totally devoid of striae, which in the C. elegans are very strong 

 and conspicuous. 



