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Show 1881.] THE SURVEY OF H.M.S. 'ALERT.' 33 the narrow end, and is 2f millims. in length and 2 broad ; the portion inserted in the tissue is larger than the exposed part, the line of demarcation being well defined ; the exposed tip exhibits parallel lines of growth. Shell large, very fragile, globose, transparent hyaline, with a slight milky cloudiness, exhibiting very fine striae of growth. Whorls 3\, very convex, and rapidly enlarging, separated by a deep suture. Spire moderately raised. Aperture exceedingly large, wider than long, oblique. Columella very arcuate, visibly perspectively spiral to the apex, coated with an excessively thin callosity. Greatest diam. 25 millims., height (when resting upon the front of the body-whorl and the basal margin of the aperture) 13 ; aperture 17|wide, 15| long. Hab. Station 1 ; Shell Bay {Cunningham). There are two species of Lamellaria mentioned by II. &A. Adams (Gen. Rec. Moll. i. p. 201) of which I can find no published descriptions. They are L. antarctica, Couthouy, and L. prcetenuis of the same author, either of which names would be very applicable to the species now described. Dr. Cunningham says:-"The animal possessed the power of shortening and elongating the tentacles. At times it crawled along the sides of the glass, filled with sea-water, in which it was kept, on its large muscular foot, the shape of which underwent constant changes ; and at others it floated on the surface of the water, with the foot uppermost." COLLONIA CUNNINGHAMI, sp. n. (Plate IV. figs. 10, 10 a.) Shell small, subglobose, perforate in the young state, when adult imperforate, of a rose-madder colour. Whorls 4\; apical one whitish, the rest convex and finely spirally striated, also marked with faint oblique lines of growth. Suture rather deep. Last whorl obliquely descending near the lip, somewhat flattened beneath near the centre. Aperture obliquely subcircular, iridescent within. Columella pearly, spread over the umbilicus. Labrum with a narrow pinkish margin within. Height 4\ millims., greatest diam. 5, smallest diam. 4\. Operculum circular, consisting of six whorls, which are most easily seen on the inner suface. The outside is somewhat thickened by a shelly deposit. Hab. Stations 5 and 2, and Wolsey anchorage, 17 fathoms, m u d and gravel bottom. Named after Dr. R. O. Cunningham, whose labours on the Patagonian fauna are well known and highly appreciated. TROCHUS (PHOTINULA) C^ERULESCENS, King. Hab. Stations 6 and 7. TROCHUS (PHOTINULA) VIOLACEUS, King. Hab. Stations 2, 5, 6, 7, and Puerto Bueno, 2-7 fms. PROC. ZOOL. Soc-1881, No. III. 3 |