481' Mr. J. W. Salter on some new Palaozoic Star-fishes. transversis tlecussatis ; regione iimbilicali impressa ; apertura sub-circulari ; labio vix incrassato ; labro simplici. Hab. Tabu-Siiiia; 25 fathoms. A small tliiii species with plicate whorls crossed by regular elevated transverse liree. 5. Genus Scaliola, A. Adams. Shell thin, turreted, perforate ; whorls rounded, agglutinate. Aperture circular ; peritreme simple, acute. Scaliola belta, A. Adams, Ann. Nat. Hist. 1860, vol. vi. Hab. Tabu-Sima; 25 fathoms. An examination of fresh specimens of this little genus proves that it has the faculty, like Helicina agf/lutinans and the species of Onustidce, of covering the surface of the valves with foreign bodies. Shanghai, China, Mav3, 1861. XLVIII. — Additional Notes on some new Palceozoic Star-fishes. By J. W. Salteu, Esq., F.G.S., Geol. Survey of Great Britain. [Plate XVm. figs. 9, 10, 11.] To the Editors of the Annals of Natural History. Gentlemen, In the Notes I sent you on the Silurian Starfishes (Annals, ser, 2. vol. xx. p. 321, pi. 9) one of the most doubtful points was the true position of the long-armed genus Protaster (fig. 4). It had all the appearance of an Oj)hiura, and yet there was so much apparent similarity to the accompanying genera of AsteriadcB as to suggest the expectation that they might be found nearly allied. A fresh set of specimens of these beautiful fossils has cleared up the point, at least so far as it shows that Protaster possessed the usual madreporic plate of the Asteriadce. Its position, and a slightly magnified view of the plate are given in the sketch, fig. 9. There were also some important differences, when Protaster was compared with the Ophiuridce, in the structure of the arms themselves ; for the number of plates in a circuit of the arm was six in Protaster, four in all ordinary Ophiurids. This number, indeed, is constant ; or if, as in Ophiolepis, the upper plate be sometimes divided, this is accidental, no species being known in
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