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Show 40 ZOOLOGICAL C O L L E C T I O N S M A D E D U R I N G [Jan. 4, SAXICAVA, sp. Hab. Station 7. There are two apparently young specimens of a species of this genus. They may possibly belong to S. antarctica, Philippi, who says('Archiv fiir Naturgeschichte,' 1845, p. 52) that it is almost impossible to separate the young of the common Greenland species {S. arctica) from the young of the Patagonian form. As far as the character of the shell can determine the species, I confess that the two little specimens from the Straits of Magellan appear to be merely the immature state of the northern shell. PANDORA (KENNERLIA) BRAZILIENSIS, Gould. (Plate V. figs. 4-4 c.) Pandora braziliensis, Gould, Sowerby, Conch. Icon. pi. 2. f. 15. Shell somewhat ovate, truncate on the hinge side. Lower or left valve deep, convex, thickish, whitish, with a shallow depression from the umbo to the anterior part of the ventral margin, parting off about one sixth of the valve into a sort of wing, which has a less length than rest of the valve ; and consequently the ventral margin is interrupted and does not form a regular curve. Down the posterior dorsal slope are three slight keels, situated close together and not far from the edge. Sculpture consisting of coarsish concentric lines of growth ; and radiating from the umbo towards the ventral margin a few rather indistinct very slightly elevated ridges may be observed. Interior whitish, pearly, iridescent. Scars small, subcircular, marked with a few transverse concentric layers of growth. Anterior thickening of the hinge-line stout, dentiform, adjoining the front scar, posterior also rather strong and projecting, forming an oblique boundary to the cartilage. The latter is supported or strengthened by a narrow delicate ossicle. Upper, right, or flat valve sculptured with fine concentric lines of growth and also with arcuate brown radiating striae. The anterior part is also parted off, as in the lower valve, by an indistinct depression from the apex to the front part of the ventral margin. Posterior dorsal slope nearly at right angles to the rest of the surface of the valve, forming an acute angle. Interior exhibiting about the central portion a few radiating shallow punctured stria?. Scars similar to those of the other valve. Teeth two, one very strong, the other thin, narrow, diverging, forming a base for the cartilage. Pearl beautifully iridescent. Width 21-g- millims., length 16, thickness 6. Hab. Station 2. This species is considerably like P. wardiana, A. Adams, from Mantchuria; but when closely compared together there appear several differences by which they can be distinguished. The form is not precisely similar ; the position of the scars is different; and the dentition is much stronger in the present species, although a smaller shell. As far as I can ascertain, Gould has not published this name; but the valve figured in Sowerby's characteristically slovenly monograph is labelled in the Cumingian collection P. braziliensis, |