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!l ! I BRITISH PALAEOZOIC FOSSILS. [ZOOPHYTA. This is more slender in form than the C. mitratum (Schl. sp.) or C. cornu-copiw (Mich.), and from which, and all the other turbinate corals of the palaeozoic rocks, it is distinguished, externally, by the strong, distinct, distant, longitudinal ridges; the internal characters approximate it only to the Cyathaxonia cornu (Mich.), from which it is distinguished by its simple, few and thick lamellae, and thick axis, as well as more tur binate form. Position and Locality.—Rare in the carboniferous limestone of Derbyshire. Explanation of Figures.—PI. 3. C. fig. 3. Natural size.—Fig. 2 a. Do. Vertical and horizontal section magnified two diameters; the former shewing the thick solid axis and very loose vesicular structure, of thin slightly curved plates, converging upwards to the axis; the latter shewing the thick radiating lamella? connected by the thin edges of the vesicular plates. Genus. SARCINULA. See page 36. Sarcinula Piiillipsii (M c Coy). Ref—M'Coy, Ann. Nat. Hist. 2nd Series, Vol. III. p. 125. Phill. Pal. Foss. f. 15. D. I have given the above name, provisionally, to a coral which I believe to be identical with the Flintshire one figured as above, by Prof. Phillips, but not named nor described. It is closely allied to the C. placenta, but is of a thicker growth, the tubes are one-third larger, usually less than their diameter apart, and surrounded by thirty-two to forty strong radiating lamella? extending to the adjoining tubes; there is an obvious tendency in the middle of the transverse diaphrams to extend upwards, to form an irregularly compressed solid axis, often visible in the weathered cups. Position and Locality.—Common in the carboniferous limestone of Cor wen. Sarcinula placenta (M c Coy). PI. 3. B. fig. 9. Ref.—M c Coy, Ann. Nat. Hist. 2nd Series, Vol. III. p. 124. Sp. CL—Corallim forming tabular masses, about one inch thick; under side with a thin epitheca, marked by small, concentric, imbricating undulations of growth, and radiating scratch-like stria?; the upper and lower surfaces parallel and fiat; composed of vertical cylindrical tubes, forming circular cells at the surface, one line in diameter, and averaging about two lines apart; the intervening space being flat, cellular, and obscurely radiated on the weathered surface by about twenty-five curved radii; vertical section, tubes irregularly transversely septate by vesicular plates; spaces between the tubes composed of slightly-waved transverse rows of small, curved, vesicular plates, forming a nearly uniform minutely cellular structure; horizontal section, tubes either plain or shewing more or less of the transverse vesicular plates; intervening spaces irregularly cellular, but shewing a slight disposition to form curved star-like lines round the tubes. This interesting coral bears a strong external resemblance to the Nematopliyllmn decipiens (M°Coy), but is distinguished by having no divisional lines between the stars in either section. Position and Locality.—Rare in the carboniferous limestone of Derbyshire. Explanation of Figures.—PI. 3. B. fig. 9. Fragment natural size, shewing the lamella? passing from centre to centre on the flat upper surface, and the edge of the mass shewing the mode of weathering in horizontal laminae, the centres remaining as persistent cylinders, vertically striated by the radiating lamella?.— Fig. 9 a. Do. Vertical section.—Fig. 9 h. Do. Horizontal section, shewing the near equality in strength of the radiating and vesicular plates, and the consequent indistinctness of the radiation. Sarcinula turerosa {M'Coy). PI. 3. B. fig. 8. Ref.—M c Coy, Ann. Nat. Hist. 2nd Series, Vol. III. p. 124. Sp. Ch.—Corallim forming large shapeless masses, the upper surface covered with irregular tuberose projections, separated by flat or concave spaces, and each having a depressed tubular centre, one line in diameter, average distance between the centres five lines; from the margin of each centre about thirty slightly sigmoidal,