TUIUiO. 191 



2. MARMORATUS, pi. i. f. 4, and iv. 34, Gmelin, Linn. p. 

 3592, n. 15; Linnseus, Syst. Nat. (12th edit.) p. 1134— 

 olearius, Gmelin, Linn. n. 17 — cochlus, Gmelin. — The largest 

 species of the genus with the exception of T, Jordani. The 

 young shell has smooth rounded whorls, as figured on pi. iv. ; 

 when fully developed the last whorl is surmounted by an ele- 

 vated, rounded, generally more or less nodulous keel, and 

 has usually one or two nodulous keels round the lower part. 

 The specimen figured in Reeve's ' Conchologia Iconica' as 2\ 

 imperudis appears to be a variety, or young specimen, of this 

 species, and not the T. imperialls of Grmelin, for which see 

 pi. iv. f. 31. y. marmoratus is very abundant in the 

 Eastern Seas, and is commonly uncoated and polished, expos- 

 ing the pearly nacre for ornamental purposes. 



3. iMPERiALis, pi. iv., f. 31, Gmelin, Syst. Nat. p. 3594 — 

 Eegenfussi, Deshayes. — Testa ovato-conica, subventricosa, 

 ponderosa, imperforata, viridis, rufo-fusco nebulata, lineis 

 rufescentibus longitudinaliter strigata, interdum zonis an- 

 gustis nigricante alboque articulatis spiraliter picta ; anfractus 

 convexi, rotundati nunc la3vi, nunc longitudinaliter rude 

 striati ; anfractus ultimus interdum superne leviter nodosus ; 

 apertura ampla, subcircularis ; peristoma simplex ; columella 

 arcuata, ad basin vix effusa. Operculum circulare, crassum, 

 extus valde convexum, ad latera sinistra incrassatum, ubique 

 granulis minutis albidis notatum. — A fine species of very 

 solid growth, generally exhibiting fine longitudinal reddish- 

 brown slightly impressed linear streaks, but some specimens 

 are coarsely and irregularly wrinkled. — Has. East coast of 

 Madagascar. 



4. PETHOLATUS, pi. V. f. 46, 47, Linnaeus, Syst. Nat. 

 (12th edit.), p. 1233 (genus Turbo). — Testa ovata, imper- 

 forata, polita, rufescente-fulva, vel spadicea, vel viridula, 

 fusco nebulata, fasciis interruptis nigro-fuscis spiraliter picta ; 

 spira plus minusve elata ; anfractus 7, convexi; anfr. ultimus 

 interdum superne depressus, inferne leviter productus ; aper- 

 tura suVjcircularis ; columella arcuata, lutea ; peristoma sim- 

 plex ; la brum luteo limbatum. Operctdum extus politum, 

 nitens, convexum, medio viridi, et ad margines castaneo et 

 albo pictum. — A beautifully painted bright shining shell, 

 \'arying both in form and marking ; the two figures represent 

 the most prevailing forms. Specimens occasionally occur 



