CONOVULUS. 191 



upon the columella, and sometimes in the throat ; its 

 peristome more or less thickened. Septa of the spire even- 

 tually obliterated. No operculum. 



Animal with two subtriangular tentacula, and two sessile 

 eyes placed at their inner bases. Foot rounded at both 

 extremities, and often sulcated transversely in the centre, 

 so as to divide it into two disks. 



Some very interesting- observations on the animals of 

 the British species of this genus, by Mr. W. Clark, are 

 contained in the Annals of Natural History, for December, 

 J 850, and July, 1851. 



C niDENTATus, Moutagu. 



White ; outer lip simple, throat smooth ; pillar with two fokls. 



Plate CX XV. fig. 1,2. 



Vvl/tta bkkntata, Mont. Test. Brit. Suppl. p. 100, pi. 30, f. 2. — Turt. Conch. 

 Diction, p. 253. — Dillwyn, Recent Shells, vol. ii. p. 507. 

 — Wood, Index Testae, pi. 19, f. 21 (magnified). 

 „ alhu, (scarcely of Mont. Test. Brit. p. 235, not Suppl. p. 101, or of 

 Maton and Rack. Trans. Linn. Soc. vol. viii. p. 130), Turt. 

 Conch. Diction, p. 250. 

 J«/«ttt/a 6/(/c«te/a (not Gould), Ferus. Tabl. Syst. Moll. p. 103. — Jeffreys, 

 Trans. Linn. Soc. vol. xvi. p. 3Gf5. — Brit. 

 Marine Conch, p. 144. 

 „ «/ia, Feri's. Tableau System. Moll, (no desc). — Jeffreys, Trans. 

 Linn. Soc. vol. xvi. p. 368. — Forbes, Malacol. Monens. p. 12. 

 — Brit. Marine Conch, p. 145. 

 Volvuria „ Fleming, Brit. Animals, p. 333. 

 Aclcoii bidcntatua, Fleming, Brit. Animals, p. 337. 

 Aarifula erusa, Jeffreys, Trans. Linn. Soc. vol. xvi. p. 369. 

 Coiiovulus bideniatus. Gray, Manual L. and F. W. Shells, p. 227, pi. 12, f. 145. 

 — Brit. Marine Conch, p. xxxiii. — Clark, Ann. Nat. 

 Hist, new ser. vol. vi. p. 445. 

 „ albus. Gray, Manual L.and F. W. Shells, p. 227, pi. 12, f. 146.— 

 Brit. Marine Conch, p. xxxiii. f. 25. 

 Auricula Miclieli, Mittre, Revue Zool. Soc. Cuvier. 1841, p. GG ? 

 Juminia bidentaia. Brown, Illust. Conch. G. B. p. 22, pi. !!, f. 7. 

 Auricula dubia, Cantraine, Bull. Acad. Sc. Brux. vol. ii. p. 383.; Mem. Acad. 

 Sc. Brux. vol. xiii. p. 172 ? 



