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Show 364 MR. R. B.WATSON ON MADEIRAN MOLLUSKS. [Mar. 18, only one specimen, which was dredged at Ponta de Sao Lourenco in 50 fathoms. By the time my men brought me the dredgings, though the animal was perfectly recognizable so far as colour went, it was yet so much decayed that it broke to pieces in the process of extraction; and to complete the misfortune, I have mislaid the lingual process, which I hastily put aside in spirits for preservation. The shell was so completely covered with a hard thick incrustation of lime as to leave no portion exposed. With great care I succeeded in cracking off this incrustation in small bits from the last whorl, leaving the epidermis quite fresh below. On the upper whorls this incrustation and the shell beneath were so honeycombed by minute annelids that both broke together, and obliged me to pause in my work ; these annelids have also produced some warts on the interior of both the outer and inner lip, which look deceptively like irregular folds or teeth. EULIMA PAIVENSIS, Watson. (Plate XXXVI. fig. 29.) Shell conic-oblong, white, strong, rounded in all its lines, broadish in the base, blunt in apex. Sculpture smooth, with the rounded lines of a thing cast, not cut. There are numerous but very faint lines of growth, and a doubtful suggestion of excessively microscopic, close-set, spiral scratches, best seen on the upper whorls ; beneath all these, as in many of tbe Eulimee, the whole texture of the shell can, under the microscope, be recognized as built up of longitudinal, microscopic, hair-like, anastomosing columns, each about y-^oo *ncn broad. The labial rib is strong and spread out. Colour semitransparent bluish white, like very much watered milk, rendered brown by the presence of the animal. Behind the labial rib there are three rusty stains, which show a tendency to extend across the body-whorl as bands ; the highest and strongest is just at the apparent marginal band below the suture ; the second is at the periphery, the third on the base. Spire elongated, conical, with its contour-lines not quite straight, but a little curved ; apex blunt and somewhat incurved. Whorls 7 to 8, very slightly rounded, of regular increase ; the last is large. Suture slight, not quite smooth, little oblique, remotely margined by the through-shining of the whorl above it. Mouth pear-shaped, being oval below, intrenched on by the curve of the belly; pointed above, and very minutely channelled at the upper corner, deep. Outer lip thick, but finely though roundly edged. Some six or eight concentric lines, which form the edges of the several accretions of which the lip is built up, may be traced one within the other. The lip retreats above, so as to form a very slight, shallow, and open sinus; below it advances a little, and has a free round sweep across the base. Inner lip is spread in the form of a pad of enamel over the pillar, which it envelops completely, and extends upwards as a thick callus |