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Show 188 MR. E. A. SMITH ON MOLLUSCA FROM JAPAN. [Feb. 18, two fine lirae in the inframedian space also gradually disappears attenuates on the upper whorls. 14. PLEUROTOMA TRIPORCATA. (Plate XIX. fig. 9.) Shell shortly fusiform, of a uniform pale brown or luteous tint. Whorls 9, the first globular, glassy, rather large, the rest encircled with three distinct keels : the uppermost is just beneath the suture; the median one (the most prominent of all) is situate in the middle of the whorls, and the lowermost a little above the lower suture: the interstices between the carinations are finely latticed with spiral thread-like lirae and raised incremental lines ; the former are about three or four in number in each of the interstitial spaces, and the latter very arcuate between the central and uppermost keel, and very oblique beneath the former : the body-whorl has about twelve additional carina? or lirae, whereof the four uppermost are stouter and further apart than those beneath. Columella a little oblique and arcuate above the middle, more sloping below ; labrum thin, very much produced in the middle, widely and deeply notched between the terminations of the uppermost and principal keels ; canal short, recurved. Length 14 millims., diam. 4\. Hab. Station 1. This is another species belonging to the same section of the genus Pleurotoma as the three preceding. They are all sculptured with the same character of ornamentation; yet in detail it is very distinct, and they also show good differences in the nuclear whorls. 15. PLEUROTOMA PATRUELIS, Smith. (Plate XIX. fig. 10.) Pleurotoma ( ?) patruelis, Smith, Ann. & Mag. Nat. Hist. 1875, vol. xv. p. 419. Hab. Gulf of Yedo, 10| fathoms. The specimen from the above locality agrees precisely with the type in colour and sculpture, hut it is rather more robust. It is 251 millims. long, and 8 broad. When describing this species I was unable to give any account of the labrum, as, unfortunately, it was broken away in the only specimen at hand. In the perfect shell it is thin, prominent in tbe middle, and broadly sinuated at the upper part in the concavity of the whorl. Columella a little oblique, covered with a callosity, thickest towards the base. Operculum sub-ovate, concentric, nucleus subcentral, but rather towards the inner or columellar side (fig. 10 a). 16. PLEUROTOMA CONSIMILIS. (Plate XIX. fig. 11.) Shell ovately fusiform, turreted, pale fleshy brown. Whorls 8 ; the first globular, glassy, smooth, the rest concave above, angled at the middle and a little concave below the angle, longitudinally flexuously obsoletely plicated ; plicae obsoletely nodulous above at the suture, bearing larger nodules at the angle and two smaller ones beneath it; nodules connected by spiral lirae between the plicae, which are coarser than other intermediate fine spiral lirations ; the last whorl encircled |