298 BRITISH FOSSIL CORALS. 
are much smaller and less irregular, and the lateral circular accretion ridges are much less 
developed. Height about 2 inches, diameter of the calice 14 inch. 
Dudley. Collection of the Geological Society, of Mr. Fletcher, Mr. John Gray, &c. 
3. CYSTIPHYLLUM SILURIENSE. ‘Tab. LX XII, figs. 1, la. 
CysTIPHYLLUM SILURIENSE (pars), Lonsdale, in Murchison, Sil. Syst., p. 691, pl. xv bis, 
1839. (Not the fig. 2, which is an Omphyma.) 
CYATHOPHYLLUM VEsIcULOsUM, Hichwald, Sil. Syst. in Esthl., p. 201, 1840. 
CYSTIPHYLLUM SILURIENSE, Milne Edwards and Jules Haime, Pol. Foss. des Terr. Palzeoz. 
(Arch. du Mus., vol. v), p. 465, 1851. 
Corallum turbinate, short, and very broad ; epitheca thick, and presenting some radici- 
form prolongations. Ca/ice subcircular, rather deep, very broad, presenting some obscure 
indications of septal strize, and occupied by large unequal vesicles, the structure of which 
is very distinct in a vertical section. Height about 13 or 2 inches; diameter of the calice 
somewhat more. 
Wenlock. Dudley (Lonsdale) ; Ardaun and Cong (M‘Coy) ; Russia (Eichwald). 
Collection of the Geological Society of London. 
The Silurian fossil described by Professor M‘Coy, under the name of Fistulipora 
decipiens,‘ much resembles a Heliolites, in which all traces of the septal apparatus have 
disappeared, and the coenenchyma does not present the vesicular structure which is charac- 
teristic of the genus Fistulipora, but is made up of small vertical tubes, divided like the 
visceral chambers by numerous horizontal tubule. 
The same paleontologist has recently added to the list of the British Silurian Corals, 
two other species, the zoological characters of which are still so imperfectly known, that 
we cannot give any decided opinion respecting their natural affinities. One of these, 
1 M‘Coy, Ann. and Mag. of Nat. Hist., 2d ser., vol. vi, p. 285, 1850; ibid., Brit. Palzoz. Foss., 
po 11 plac; figs, 185i: 
* Corallum torming hemispherical or sub-cylindrical masses, three or four inches in diameter, con- 
centrically wrinkled at base ; cell-tubes straight, sub-parallel, with moderately thick walls, leaving clearly 
definite, circular, smooth-edged cells in the transverse section, very regular in size and disposition ; usually 
slightly less than half a line in diameter, and averaging rather less than their diameter in the shortest line 
between adjacent cells, in which line there are usually two, or more, rarely three, of the intermediate 
vesicular cellules; about eighteen of the intermediate or polygonal cellules in the space of two lines; 
diaphragms in the small tubes slightly more or less than their diameter apart, two interdiaphragmal spaces 
in the large tubes slightly exceeding the diameter. 
«Wenlock Limestone, near Aymestry, Herefordshire.’ (M‘Coy, op. cit.) 
