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22 BRITISH PALAEOZOIC FOSSILS. [ZoOPHYTA. formed for those Favosites with branches composed of oblique divaricating tubes. I find that the tubes are hexa gonal in the interior, but distinguished remarkably from the true Favosites by the great thickness of the walls, especially at the surface, where they resemble an abundant compact ccenenchyme, widely separating and often almost closing the apertures. I have only indistinctly seen the connecting pores. CCENITES INTERTEXTUS (.EidlW.) Ref. and Byn.—Eichwald, Zool. Bpecialis, t. 2. f. 16, and remarks, p. 42, of Urwelt Russlands; = Limaria clatlirata. Lonsd. Sil. Syst. t. 16. bis. f. 7. Bp. Ch.—Corallum forming irregular, cylindrical or compressed branches, two or three lines in diameter, dichotomising irregularly, and occasionally anastomosing; apparent coenenchyme very abundant and compact; cells three to four in an oblique line in the space of one line; when most developed, quincuncially arranged, rather less than their diameter apart, triangular, usually broader than long, anterior margin, broadly rounded, posterior or inferior prominent angle separated from the lateral angles by a large prominent tooth, projecting inwards from each of the straight sides; in other states the posterior angle shortens, and the arched cells nearly close by the increased thickness of the compact intervening tissue, leaving slender transverse doubly- arched impressed lines, for the cell-apertures; in other states (probably worn) the compact pseudo-ccenenchyme is of very variable extent, and the cell-openings are of very irregular size and shape, for the most part tri angular, rhombic, or irregularly rounded; surface under the lens between the cells very minutely granular, and marked with concentric lines round each opening; transverse diaphragms rather more than the diameter of the tubes apart. The changes of form in the apertures of the cell-tubes in this coral are extremely remarkable and difficult to account for, but do not in practice cause much difficulty, as almost every specimen shews in some part the characteristic transversely-arched triangular forms of the perfect cells; the triangular or irregular form of the apertures, and their being separated by such a distance of compact interstitial matter, or thicked walls, pre vents this coral being confounded with any of the polygonal-celled Favosites, or round-celled Stenopores. Position and Locality.—Common in the Wenlock limestone near Aymestry, Herefordshire, in company with the Favosites ? oculata (Gold.) sp. also in the Wenlock limestone at Dudley, Staffordshire; one very irregular doubtful specimen from the Wenlock limestone near Sedgely. CCENITES STRIGATUS (M c Coy). PI. 1. C. fig. 8. Ref.—M c Coy, Annals Nat. Hist. 2nd Series, Vol. VI. Bp. Ch.—Corallum forming cylindrical, dichotomous branches, two to three lines in diameter; surface with small, narrow, triangular cells, the base of the triangle below, and the apex usually more or less pro longed upwards into a vermiform channel, often upwards of half a line long; four to five rows of cells in the space of one line, measured transversely, about two in the same space measured longitudinally; compact interstitial space between the rows of cell-openings usually rather exceeding their width. The usual compact appearance of the Coenites combined in this species with the interrupted scratch-like channels of the cell-mouths, completely distinguishes it from any species of Favosites or Stenopora. Position and Locality.—Not uncommon in the Wenlock limestone of Dudley, Staffordshire. Explanation of Figures.—Plate 1. C. fig. 8. Branch natural size, from Dudley.—Fig. 8 a. Portion of do. magnified four diameters. Genus. NEBULIPORA (APCoy). Ref.— M e Coy, Ann. Nat. Hist. 2nd Series, Vol. VI. p. 282. Gen. Char.—Corallum incrusting or forming lenticular masses, with a concentrically wrinkled epitheca below; composed of small prismatic tubes perpendicular, or nearly so, to the upper surface on which they open; among the small tubes, are regularly arranged clusters of similar tubes of rather larger size ; all the tubes in contact, traversed by horizontal diaphragms at regular distances, (walls apparently perforated by rows of small foramina).