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Show 1881.] THE SURVEY OF H.M.S. 'ALERT. 37 Apparently distinct, although a near relation to H. saxatilis of Couthouy, from Tierra del Fuego. S U C C I N E A PATAGONICA, sp. n. (Plate IV. figs. 17, 17«.) Shell ovate, somewhat ventricose, greenish yellow, with the apex light scarlet. Whorls 3, very convex; the last somewhat elongated, striated by the lines of growth, and separated by a deepish suture. Mouth ovate, equalling rather more than two thirds of the entire length. Columellar margin obliquely arcuate, with a thinly reflexed enamel extending to the termination of the outer margin. Length 12| millims., diam. from lip to opposite side of the whorl 8, aperture 9 long and 6 broad. Another specimen is 9 millims. long, 6| broad, and its aperture has a length of 6f and a width of 5. Hab. Cockle Cove, found on dead leaves; also shores of Trinidad Channel and Puerto Bueno. This species is mainly distinguished from S. magellanica of Gould by its scarlet apical whorl, the second or penultimate being rather less shouldered; and the suture, too, is scarcely as deep. c. Fluviatile. C H I L I N A AMCENA, sp. n. (Plate IV. figs. 18, 18a.) Shell very fragile, ovate, acute above, greenish yellow, with transverse bands of dark reddish brown, more or less arrow-head-shaped spots or marks, which sometimes flow into one another from band to band, thus forming longitudinal zigzag streaks. Of these series of spots the body-whorl has five-one immediately beneath the suture, and the others at subequal distances ; that which is a little above the middle of the whorl and runs into the suture of the penultimate whorl is, in the eight specimens before me, narrower than the bands immediately above and beneath it. The whorls are well rounded, about six in number, and striated with the lines of growth. Aperture inversely subauriform, coated with a thin bluish-white enamel, but exhibiting the exterior banding, and, as a rule, occupying about § of the entire length of the shell. Columella a little oblique and arcuate, with a single fold at the upper part, white, somewhat reflexed beneath the fold, and with a thin callosity above it. Length 26 millims., diam. 11, aperture 14| long and 6 broad. Hab. From a lake near T o m Bay. The spire in this species is quite as long as in C. parchappi, d'Orbigny, from which species it differs in the brightness and distinctness of coloration, the greater convexity and shouldering of the whorls, and the different character of the columella. C. pulchra, d'Orb., is more like in colour; but its form is much more stumpy, and the columella and the fold upon it are considerably thicker and heavier than in the present species. III. CONCHIFERA. V E N U S , sp., jun. Hab. Station 2. Of this species there are two specimens, which apparently are im- |