CERITIITUM. 201 



one that margins the outer lip of fully matured individuals. 

 The mouth occupies about a fourth of the entire shell, has a 

 roundish subquadrate shape, and is very nearly as broad as it is 

 long. The edge of the much arcuated outer lip is at first in- 

 curved and then convexly projects towards the base of the shell. 

 The throat is smooth. The pillar is nearly straight, and often 

 pallid : there is no canal at its extremity but merely a sinus. 

 Length fully five lines ; extreme breadth a line and three 

 quarters. 



A common W. Indian shell ; introduced by Da Costa as 

 Cornish. The varieti/ turboforme was constituted from specimens 

 in ivhich the revolving basal thread ivas obscure, or 7iot 2n'esent, 

 and the ribs coarser than tisual ; the advisability of suxipressing it 

 as a species was suggested by Montagu himself. 



C sunuLATUM, Montagu. 



i\r>(rej' snhulalus, Mont. Test. Brit. Suppl. p. 115, pi. 30, f. 6. — Tuut. Cniicli. 

 Diction, p. 96. — Dillw. Recent Shells, vol. ii. p. 7.').0. — 

 Wood, Index Testae, pi. 28, f. 168. 

 Terehra snhulata (not Lamarck), Fleming, Brit. Animals, p. 347. 

 C'erilhium sidmlalum (not Lamarck), Brit. Marine Conch, p. 194. 



„ elnqans. Blainv. Faune Franq. Moll. p. 159, pi. 6, a. f. 9. — Desh. 

 Anim. s. Vert. vol. ix. p. 323 (probably). 



Subulate, tapering regularly from base to apex, not very 

 strong, not varicose, pale squalid yellow, with a single very dark 

 brown narrow band winding along the top of each turn, and 

 passing slightly over the narrow suture ; base of the body of a 

 similar dark colour. Whorls very numerous (we counted four- 

 teen on our largest example), extremely short, very slowly in- 

 creasing in length, so flat that the lateral outlines of the shell 

 are nearly rectilinear, adorned above and below with a row of 

 horizontally compressed concatenated blunt granules, that are 

 equally numerous, but slightly larger, on the base. The inter- 

 vening central area, which to the eye seems smooth, is traversed 

 by scarcely raised rounded longitudinal costella) (one for each 

 granule, and in continuous lines with them), and is at least half 

 as long again as the larger grains : a very fine revolving line suc- 

 ceeds the upper series of granules upon two or three of the lower 



VOL. III. D D 



