CORALS FROM THE SILURIAN FORMATION. 295 



Corallum massive, subgibbose; epitheca thin. Calicinal circles small, and circum- 

 scribing a shallow, but well marked central fossula. Costo-septal radii very delicate, 

 closely set, very flexuous, unequally developed alternately, extending to a considerable 

 distance, and confluent with those of the adjoining individuals. Some appearance 

 of a pseudo-columella produced by the inner extremity of the large septa; some 

 of which are slightly curved. 35 or 40 of these occupy the calicinal space, 

 but exteriorly the number of the septo-costal ridges augments greatly, and varies much. 

 Diameter of the calicinal circles 2§ or 8 lines ; depth of the calicinal fossula about half a 

 line. A vertical section shows that the vesicular tissue is rather dense, the cells somewhat 

 unequal in size, and presenting vertical septo-costal stria?, in general distinct, although 

 small. 



Much Wenlock. 



Specimens are in the Collections of the Museum of Practical Geology, of the Parisian 

 Museum, of Mr. Bowerbank, and M. de Verneuil. 



This coral differs from all the other species of the genus Strombodes in not having any 

 trace of exterior walls between the individuals. 



9. Genus Syringophyllum (p. lxxii). 



Syringophyllum organum. Tab. LXXI, figs. 3, 'da, 33. 



Madrepora composita, &c, Fougt, Arasen. Acad., vol. i, p. 96, tab. iv, fig. 6, and No. 1, 



1749. 

 — organum, Linne, Syst. Nat., edit. 12, p. 1278, 1767. 



Sarcintjla organon, Schweigger, Handb. der Naturg., p. 420, 1820. 



— organum, Goldfuss, Petrel". Germ., vol. i, p. 73, tab. xxiv, fig. 10, 1826. (Not 



Lamarck.) 



— organon, Eichwald, Zool. Spec, vol. i, p. 189, 1829. 



— organum, Holl, Handb. der Petref., p. 401, 1830. 



— — De Blainville, Die. Sc. Nat., vol. lx, p. 314, 1830.— Man., p. 348. 



— — Morren, Descr. Cor. Belg., p. 67, 1832. 



— — Hisinger, Letb. Suec, p. 97, tab. xxviii, fig. 8, 1837. 

 — . — Eichwald, Sil. Syst. in Estbland, p. 199, 1840. 



Astreopora organum, D" Orbigny, Prodr. de Paleont., vol. i, p. 50, 1850. 



Sarcinula organum, M'Coy, Brit. Palseoz. Foss., p. 37, 1851. 



Syringophyllum organum, Milne Edwards and Jules Haime (Introd., p. lxii, 1850), Pol. 



Foss. des Terr. Palseoz. (Arcb. du Mus., vol. 5), p. 490, 



1851. 



Corallum massive, astreiform, rather tall ; gemmation lateral ; calices of unequal size, 

 circular, rather prominent, and placed at a distance from each other about equal to their 

 diameter; costas thin, but slightly prominent, equally developed, separated by large furrows, 

 straight or slightly flexuous, and extending to the bottom of the inter calicular space, where 



