A monograph of the British fossil corals - kreidefossilien.de

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BRITISH FOSSIL CORALS.
19. Gciuis Ctenophyllia.
Dana, Zoophytes, p. 169, 1846.
Corallum pedunculate, but increasing very little by its basis,
and terminated by a large
oval, almost fiat, calicular sm-face ; the different series of corallites intimately united together
by means of their common walls, and without there being in general any cceneuchyma ; the
gyi'i or calicular grooves very long, and the mural ridges thin. Columdla lamellar, and
aimost uninterrupted from one end of the gyrus to the other. In general, some traces of
pall. Septa rather closely set, slightly exsert, and delicately granulated. Dissepiments very
abundant, arched, and oblique ; sometimes simple, but in general producing a vesicular
mass.
Tiie common epitheca rudimentary, and covering only the inferior part of the common
exterior walls, in the upper part of which are costa, nearly equal, and more or less cristiform
near the margin of the calicular surface.
Typ. sp., CtenojihyUia mceandrites, Milne Edw. and J. Haime, Ann. des Sc. Nat., 3"" serie, vol. x, p. 277 ;
Meandfina pectinafa, Lamarck ; Madrej). mcBandrites, Solander and Ellis, Zooph., tab. xlviii, fig. I.
20. Genus Dendrogyra.
Ehrenberg, Corall. des Roth. Meeres, p. 100, 1834.
Corallum composite, having the form of a thick, massive, vertical column, in which the
corallites are placed perpendicularly to the axis, and constitute very tortuous gyri,
completely united by their walls ; mural ridges broad, flat, and compact ;
grooves shallow.
Coliniiella highly developed, and formed by a series of very compact, enlarged processes.
Septa very thick and closely set. Bissepiments large, but not crowded.
Typ. sp., Dendrogyra cylindrus, Ehrenb., op. cit. ;
Milne Edw. and J. Haime, Ann. des Sc. Nat., 3"" serie,
Zool., t. X, pi. vi, fig. 9.
21. Genus Rhipidogyra.
Milne Edw. and J. Haime, loc. cit., p. 281, 1848.
Corallum composed of a single series of corallites and constituting a flabelliform or
tall tortuous mass, the lateral walls of which are always free from top to bottom. Columella
lamellar, but almost rudimentary. Septa exsert and crowded, Bissepiments abundant.
Costce delicate, in general subcristate near the margin of the calice. No epitheca, or only
a rudimentary one.
Typ. sp., Rhipidogyra flabellum, Milne Edw. and J. Haime, loc. cit. ; Lobophyllia Jlabellum, Micheliu,
Icon., tab. xviii, fig. 1.
22. Ge7ms Pachygyra.
Milne Edw. and J. Haime, loc. cit., p. 468, 1848.
Corallum adherent by a very thick jieduncle ;
gyri with a narrow calicular groove,
and united by a very broad mass of dense coenenchyma. Columella lamellar. Septa
crowded. Costa delicate and granulated ; little or no epitheca.
Typ. sp., Pachygrjra labyrinthica, Milne Edw. and J. Haime, loc. cit. ; Loboptiyllia labyrinthica, Michelin,
Icon., pi. Ixvi, fig. 3.