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ZOOPHYTA.] UPPER PALAEOZOIC RADIATA. 109 SlPHONODENDRON SEXDECIMALE (.Pllill. $p.) Ref. and Syn.—Lithodendron id. Phil. Geol. York. t. 2. f. 11, 13. Sp. Ch.—Corallum forming loosely branched masses; cell-tubes slightly flexuous, subparallel, averaging slightly more than one line in diameter, and usually rather less than their diameter apart, branching at an acute angle, the branches attaining their full diameter at about four lines long; outer wall very thick, smooth, with faint transverse lines of growth, without distinct costal striae; axis strong, solid, persistent; transverse diaphragms nearly horizontal, strong, three interdiaphragmatal spaces in one line; radiating lamellae of moderate thickness, sixteen long, reaching quite to the axis, or a few occasionally uniting branch-wise with their neighbours; an equal number of very short marginal ones, one between each pair of primary. The very small size of the branches, and small number of the lamellae, easily distinguish this rare species from its congeners. Position and Locality.—Not uncommon in the carboniferous limestone of Kendal, Westmoreland; impure carboniferous limestone of Lowick, Northumberland; also at Burdiehouse; and carboniferous limestone of Derbyshire. Family. ASTRAEIDJE. See page 36. Subfamily. EUSMILINAE. See page 36. Genus. CYATITAXONIA. See page 36. Cyatiiaxonia cornu (Mich.) Ref.—Michelin, Icon. Zooph. t. 59. f. 9. Sp. Gli.—Corallum very small, slightly curved when young, nearly straight when old, the adult diameter of about three and half lines, is reached at about six lines from the apex; sometimes an inch in length with the same diameter; axis prominent, thick, solid, cylindrical, about one fourth the diameter of the tube; radiating lamellae appearing in small terminal cups as thirty-five or thirty-six alternately larger and smaller lamellae, which unite in pairs near the axis: horizontal section of larger specimens shew twenty-four radiating lamellae, extending from the axis a short way, and then splitting into a pair of slender ones, extending to the walls; no connecting vesicular plates; external surface with distinct, obtuse, close vertical striae (about five in one line) branching not unfrequently; no transverse vesicular plates. I have compared the specimens described with one from the original locality of Tournay, and find the coincidence exact. Position and Locality.—Rare in the carboniferous limestone of Derbyshire; and Kendal, Westmoreland. Cyathaxonia costata (M c Coy). PI. 3. C. fig. 2. Ref.—M c Coy, Ann. Nat. Hist. 2nd Series, Vol. III. p. 6. Sp. Ch.—Elongate-conic, generally about one inch long and half an inch in diameter at the cup, which is circular and horizontal; surface irregularly wrinkled transversely, and marked longitudinally with remarkably, thick, strong, sharply-defined striae, about seven in one-fourth of an inch; central solid axis very thick (often one line in diameter), and from it twenty-five thick, wedge-like, vertical lamellae, radiate to the walls; transverse versicular plates connecting the lamclke exceedingly delicate; in the sections the vertical lamellae are seen to dichotomize upwards, and the large curved plates of the loose vesicular structure incline upwards and inwards towards the axis.