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Show 404 DR. GWYN JEFFREYS ON MOLLUSCA OF THE [Apr. 16, furnished at its edges with short and very delicate close-set cilia different lengths and sizes, which project somewhat beyond the valves, as in T. caput-serpentis. The tubercles which close the tubular perforations in the shell are extremely small and numerous. In some large and unusually thick valves dredged by Dr. Carpenter in H.M.S. 'Shearwater,' off the coast of Tunis, the perforations are irregular or unsymmetrical, as in T. grandis. Var. 1. minor, Philippi, = T. affinis, Calcara. 'Porcupine' Exp., 1H70: Mediterranean, St. 58, 266 f. Off Jan Mayen's Isle, 263 f. (Friele, as T. arctica) ; Mediterranean, Adriatic, and iEgean, 30-310 f.; 'Challenger' Exp., off Cape of Good Hope, 150 f., and Azores, 1000 f. ; ' Josephine ' Exp., off Villa Franca, Azores, 320-600 f.; Japan, 55 f. (A. Adams, as T. davidsoni). In a specimen of this variety from the Bay of Naples the front margin is cloven or deeply indented, apparently in consequence of the mantle having been injured in that part. Var. 2. sphenoidea, Philippi. (Plate XXII. fig. 6.) 'Porcupine' Exp., 1870: Atlantic, St. 16, 994 f., 24, 292 f.; 25, 374 f. Gulf of Florida, 100-270 f. (Pourtales, as T. cubensis). After a protracted and very careful examination of m y specimens, which I had considered the T. sphenoidea of Philippi, and having compared them with fossil specimens sent me by Professor Seguenza as Philippi's species from the Sicilian Tertiaries, as well as with a series of T. cubensis which I received from Count Pourtales and Professor Alexander Agassiz, and also after a close comparison of all these specimens with the description and figures given by Philippi, Seguenza, Pourtales, and Dall, I am convinced that T. sphenoidea and T. cubensis are the same, and constitute a well-marked variety of T. vitrea. The loop in T. sphenoidea and T. cubensis is precisely similar. The shape and proportions of the loop depend on the shape of the shell in T. vitrea, and, I believe, in every other species of Terebratula. Some recent and fossil specimens of this variety exhibit more or less distinct, although slight, longitudinal striae, which radiate from the beak and are especially visible at the sides ; and the same kind of sculpture is occasionally observable in specimens of the typical form of T. vitrea. As to synonyms, 1 cannot recognize any valid character that would serve to distinguish Seguenza's Sicilian Tertiary species, T. elliptica and T. michelottiana from T. vitrea, or his T. miocenica, T. orbiculata, and T. benoitiana from the variety sphenoidea. T. manticula of Fischer (Journ. Conch, t. xvii. p. 81, pl. iii. fig. 4), a Miocene fossil of the south-west of France, seems to be closely allied to the variety minor, the only difference being that the deltidium in the fossil is larger. T. cernica of Crosse, from the Mauritius (Journ. Conch, t. xxi. p. 285, and xxii. p. 75, pl. i. fig. 3 ), may be also the present nearly ubiquitous species. Costa, in his ' Fauna del Regno di Napoli,' refers the T. |