1890.] MARINE MOLLUSCA OF ST. HELENA. 315 



and Sowerby. The latter has, correctly I think, cited P. tinctus and 

 P. albus of Reeve as synonyms. In this category I should also place 

 P. sentis and P. textilis of the same author. 



EXPLANATION OF THE PLATES. 

 Plate XXI. 



Fig. 1. Pleurotoma {Clavus) amanda, ]>. 255. 



2. ( ) alhobalteata, p. 255. 



3. {Drillia) turtoni, p. 256. 



4. {Mangilia) suhquadrata, p. 256. 



6. ( ) mellissi, p. 257. 



6. - — — (Claihurella ?) multigranosa, p. 258. 



7. Miirex {Ocinchra) alboangulatus, p. 259. 



8. Lachesis helenee, p. 260. 



9. Cantharus ( Triionidea) alhozonatus, p. 260. 



10. ( ) consanguincm, p. 260. 



11. ( ) lievis, p. 261. 



12. Columbdla {Miirclla) saiictcB-helencs, p. 262. 



13. Triton turtoni, p. 268. 



13 a. ; young. 



14. Natica turtoni, p. 2()9. 



14 a. ; operculum, p. 270. 



15. tcsniata; opercuhim, p. 270. 



16. &anct<s-hdenm, p. 270. 



17. Solarium ordinarium ; upper side, p. 281. 

 17 a. ; front view. 



17 h. ; lower side. 



18. Eulima (Suhularia) fnscopunctata, p. 280. 



19. Littorina helcnce, p. 283. 



20. Biala fuscopicta, p. 286. 



21. Eissoa cala, p. 288. 



22. ephamilla, p. 288. 



23. agapeta, p. 289. 



24. wallichi, p. 289. 



25. Barleeia congenita, p. 290. 



26. Triforis atlantica, p. 292. 



Plate XXIL 

 Fig. 1. Mitra {Cancilla) turtoni, p. 266. 



2. (Pusia) sancics-heknee, p. 265. 



3. Obeliscus {Syrnola) purnilio, p. 275. 



4. Turbo (Collonia) adtnissus, p. 294. 



5. Basterotia obloni/a ; lateral view, p. 303. 

 6 a. ; dorsal side. 



6. Liioina inconspicua, p. 304. 



7. ( Codakia) compacta, p. 304. 



8. Area sanctw-helence ; lateral view, p. 305. 

 8 a. ; dorsal side. 



8 b. ; ventral side. 



9. Pectenatlanticus, p. 306. 



9 a. ; sculpture magnified. 



9 6. ; sculpture of left valve. 



10. (Janira) turtoni ; right valve, p. 306. 



10 a. ( ) ; left valve. 



Plate XXIII. 



Fig. 1. Pleiirofoma (C'lavws) prolongata, -p. 255. 



2. (Mangilia) gemma, p. 256. 



3. (ClathnrellaVj commutabilis, p. 257. 



4. ( ) usta, p. 258. 



