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MARINE MOLLUSCA. 613203. Pterocera lambis, Linn. 37, VI. IX.204. Pterocera chiragra, Linn. 37, VI. IX.205. Terebellum terebellum, Linn. {Terebellum punctaium, Reeve, 37, VI.) II— VI, X.Family CERITHIIDAE.206. Triforis corrugatus. Hinds, 20, a, 8. X.207. Triforis elegans. Hinds, 20, a {T. jncturatus, Sowerl)y, 40, e). IX.I have compared the tyjje of T. picturatus with authentic specimens of the present speciesand have no hesitation in pronouncing them specifically the same. Although Mr Sowerby describedhis shell as having three keels on a whorl, there are in fact four, and they alternate, larger andsmaller, as stated by Hinds. No mention is made by either author of the spotted carina belowthe periphery of the body-whorl. Triforis is a genus wiiich wants monographing by a competentperson, and ought to be illustrated with much enlarged [ihotographed figures. At present it ispractically impossible to identifj' most of the described species by means of the published figuresand descriptions.208. Triforis sculptus. Hinds, 20, a. XIV.This species varies much in size, and is sometimes considerablj' larger than the shell figuredby Hinds or the dimensions given in his original description'. The largest specimen in the BritishMuseum is 20 mm. in length, whereas another, equally adult, is only 1-5.209. Triforis lilaceocinctus, n. sp. (PI. XXXV. fig. 1.5). XIV.Testa elongato-pupoidea, supra acuminata, granulis flavescentibus et albis, lirata, inter granularufo punctata; anfractus circiter L5, superiores liris duabus granosis aequalibus instructi, paucianteriores lira graciliore mediana, dilute lilacea, vix granulata ornata, sutura lineari sejuncti, microscopicespiraliter striati, ultimus circa basim lilaceus, liris aliis tribus nodulosis, rufo punctatis,instructus ; apertura obliqua, piriformis ; canalis parvus, dextrorsus, semiclausus.Longit. 10|^ mm., diam. 3^ mm.A general glance at this pretty species gives the impression that the whorls have each twoadjacent rows of large granules. Such however is not the case. It is the lower row in one whorlbeing adjacent to the upper one in another (the linear suture being between) that gives thisappearance, the unspotted and more slender median lirae also lending to the effect. This liragradually dies out as it ascends the spire, so that the upper whorls have only two rows of equalsized granules. This species also occurs at the Mauritius (Brit. Mu.s.).210. Triforis excellens, n. sp. (PI. XXXV. figs. 16, 17). V.Testa magna, dilute fuscescens, hie illic saturatius maculata; anfractus numerosi (2.5— 30), plani,cingulis tribus aequalibus acutis cincti, inter cingula laeves, ultimus ad peripheriam bicingulatus,infra vix convexus, liris 4—5 instructus ; apertura irregulariter quadrata ; labrum teuue ; columellacallo reflexo crassiusculo induta.Longit. 29 ram., diam. 6 mm.The spirals are equal in size, but the space separating the lowermost from the median oneis a little broader than the groove between the upper two. The suture except at the upper partof the spire is marked with a spiral thread.' Ann. Mtifi. Nat. Hist. 1843, vol. xi. p. 17.G. II. 79