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Show 1890.] MARINE MOLLUSCA OF ST. HELENA. 255 middle by the bluish-white irregular zone dotted and spotted with olive-brown. The spire is either almost uniformly dark chestnut-brown, or else white, blotched with that colour. Some small specimens, about f inch long, which I believe to be the young of this species, are still more brightly coloured, being more or less copiously blotched with brown-black ; and the spire is radiately lined and spotted with the same tint. CONUS sp.? A single much-worn shell is all that was obtained. In general form it is very like C. tinianus, but seems to be thicker and more strongly striated transversely. It is livid in colour, and marked with longitudinal and transverse bands of an olive-brown tint, which are not, however, sharply denned, but blend at the edges into the ground-colour of the shell. The whorls of the spire are dark livid on the upper half and pale beneath, forming a light spiral zone which revolves up the spire above the suture. PLEUROTOMA (CLAVUS) AMANDA, Smith. (Plate XXI. fig. 1.) Pleurotoma (Clavus) amanda, Smith, Ann. & Mag. Nat. Hist. Sept. 1882, p. 207. The locality of this species was unknown at the time it was described. The fresh specimens from St. Helena have the transverse zone of a brighter tint, somewhat pinkish red. In certain examples it is interrupted between the ribs, and occasionally a fine reddish line occurs at the upper part of the whorls a little below the suture. This species is very closely related to P. sinuosa, Montagu, and may eventually prove to be merely a variety of it. PLEUROTOMA (CLAVUS) PROLONGATA. (Plate XXIII. fig. 1.) Testa elongata, turrita, alba vel rubescens; anfractus 6-7, duo apicales Iceves, mctgni, globosi, secjuentes superne vix concave in medio angulati, inferne conspicue contracti, costis flexuosis circa 12 instructi; apertura parva, brevis, longit. totius 5 adcequans ; anfr. ultimus costa valida variciformi longe pone labrum munitus ; labrum tenue, haud incrassatum ; sinus profundus, magnus; columella rectiuscula, callo tenui labro juncta j canalis brevissimus, latus. Longit. 6 millim., diam. 2. This species is remarkable for the great length of the spire in proportion to that of the aperture. Besides the ribs, the surface exhibits fine wavy stria? of growth. PLEUROTOMA (CLAVUS) ALBOBALTEATA. (Plate XXI. fig. 2.) Testa parva, fusiformi-ovata, pallide fuscescens, circa medium anfr. superiorum et ad basim anfr. ultimi albida ; anfr. 6, primi duo Iceves, convexi, cceteri pernio excavati, ad latent convexiusculi, costis crassis 10-12 superne subobsoletis, ad suturas indistincte 18* |