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Show 1878.] ON SHELLS FROM CHINA AND JAPAN. 727 14. Descriptions of two new Species of Shells from China and Japan. By C A R L BOCK, F.G.S. &C. [Eeceived June 18, 1878.] (Plate XLVI.) T E L L I N A W R O B L E W S K Y I . (Plate X L V I . figs. 1, 2.) Shell subovate, slightly inequilateral, gaping at both ends, marked with coarse and rather distant concentric lines of growth, covered with fine radiating striae, pellucid at intervals, with concentric opaque layers, the posterior region also being somewhat opaque. Colour bluish white stained with grey, especially at the posterior end. The latter portion is ^ longer than the anterior, acuminately produced, and terminates in a somewhat obtuse angle. Anterior margin rounded, ventral but slightly arcuate, almost rectilinear near the middle; posterior dorsal slope deeply excavated, the valves being strongly carinate from the umbo towards the posterior extremity, with a deep excavation between the keel and the extreme margin. Cardinal teeth 2 in the left valve, 1 in the right. Anterior muscular impression very elongated near the margin, posterior irregularly quadrate. Ligament situated on a narrow ledge of the posterior dorsal slope, marked off by an incised line, and extending from the umbo nearly 20 millims. In both valves (principally towards the umbones) there are rather large and irregular pittings. Pallial sinus very deep, forming a subacute angle, which extends anteriorly beyond the umbo. Breadth 112 millim., length 61 millim., diameter, with the valves closed, 39 millim. Hab. China. The magnificent species here described is one of the largest of the family (Tellinidae), and resembles in outward appearance certain species of the genus Anatina. I propose to associate with this beautiful shell the name of Dr. Wroblewsky of Copenhagen. TROCHUS (THALOTIA) YOKOHAMENSIS. (Plate XLVI. fig. 3.) Shell imperforate, acutely pyramidal, dull white, marked at intervals with irregular dark brown blotches, and the base ornamented with brown lines radiating from the centre (where they are paler, almost orange) to the periphery. Whorls 7, quite flat, spirally ridged ; ridges crenulate or subgranular through being crossed by oblique raised striae or lirulae ; on the upper whorls there are about six ridges, and on the last, which is acutely angled at the middle, they are about fourteen in number, that at the carina consisting of two or three small approximated ones, and hence broader than the rest. Aperture slightly oblique, subquadrate, upper half above the carina shallowly sulcate, lower portion smooth; columella white, callous, terminating in an oblique slight truncation. Greatest diameter 15 millim., length 18. Hab. Yokohama, Japan. |