292 BRITISH FOSSIL CORALS. 



7. Genus Acervularia (p. lxx). 



Acervularia luxurians. Tab. LXIX, figs. 2, 2a, 2b, 2c, 2d, 2e, 2/. 



Madrepora composita, &c, Fougt, Arasen. Acad., vol. i, p. 93, tab. iv, fig. 8, 1749. 

 Fungites, Thomas Pennant, Phil. Trans., vol. xlix, 2d part, p. 515, tab. xv, fig. 11, 1/57. 

 Madrepora ananas (pars), Linne", Syst. Nat., edit. 12, p. 1275, 1767. 



— truncata, Parkinson, Org. Rem., vol. ii, pi. v, fig. 2, 1808. (Not Linne.) 



— ananas, Parkinson, Ibid., pi. v, fig. 1. (Not Linne.) 

 Floscularia luxurians, Eichwald, Zool. Spec, vol. i, p. 188, tab. xi, fig. 5, 1829. 

 Astrea ananas, Hisinger, Leth. Suec, p. 98, pi. xxviii, fig. 1, 1837. 

 Garyophyllia truncata, Hisinger, Ibid., p. 101, pi. xxviii, fig. 14. 

 Cyathophyllum dianthus (pars), Lonsdale, in Mnrchison, Sil. Syst., p. 690, pi. xvi, 



figs. 12a, \2d, 1839. (Not Goldfuss.) 

 Astrea ananas, Lonsdale, Ibid., p. 688, pi. xvi, fig. 6. (Not Lamarck.) 

 Lithostrotion Lonsdalei, TfOrbigny, Prodr. de Paleont., vol. i, p. 48, 1850. 

 Acervularia ananas, M'Coy, Brit. Paleeoz. Foss., p. 35, 1851. 



— luxurians, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palseoz. 



(Arch, du Mus., vol. v), p. 415, 1851. 



Corallum composite, massive, convex ; in general tall. Corallites sometimes free 

 laterally and cylindrical, but in general united by their walls, and compressed so as to 

 become prismatical. In some cases the individuals so united diminish in diameter as they 

 grow up, and so become again free and cylindrical. Epitheca thick in the aggregate as 

 well as in the free corallites, and forming on the surface of the massive corallum delicate, 

 zigzag, slightly prominent, polygonal lines, that separate the individuals from each other. 

 Gemmation principally calicinal. Calices vary much in size, and are rather deep in the centre. 

 Septa nearly equally thick exteriorly, but unequally developed inside of the interior wall, the 

 large ones only extending to the centre ; in general 54 in large corallites, and about 30 

 in the small ones. The area comprised between the two walls terminated by a flat or 

 slightly concave surface. Breadth of the large polygonal individuals about 6 lines ; the 

 small ones about 2 lines. Diameter of the true calice or central fossula about half the 

 diameter of the corallites in large specimens, but much more proportionally in the small 

 individuals, where the space comprised between the two mural investments is but little 

 developed. 



Dudley, Wenlock. Ledbury, Herefordshire (M'Coy). It is also met with in Gothland 

 and Dalecarlia. 



Specimens are in the Collections of the Bristol Museum, Parisian Museum, of the 

 Museum of Practical Geology, of Mr. Fletcher, Mr. John Gray, Mr. Bowerbank, 

 M. Bouchard-Chantereaux, and M. de Verneuil. 



This coral may be easily distinguished from the other species of the same genus by the 

 development of its inner walls, and its mode of gemmation, which is almost entirely 

 calicinal. 



