254 BRITISH FOSSIL CORALS. 
Corallum massive, hemispherical, free ; its edge thin, and its under surface slightly 
concave, and covered with a strong epitheca wrinkled concentrically. Cadices circular, 
almost equal in size, not closely set, and terminated by a very thin, not exsert, margin. 
Coste very slender, and meeting directly those of the adjoining corallites under an angle, 
or else bifurcating and joining small transverse lamine, so as to constitute small polygonal 
divisions between the calices. These coste are not closely set; they do not always 
correspond to the septa, and they often bear some small tubercles laterally. The calicular 
fossulz are not very deep, and contain 12 very slender septa, which extend almost to the 
centre, and are somewhat irregular in size. Diameter of the calices almost one line; 
distance between them somewhat more. 
A vertical section shows that the wad/s are slender, but still very distinct, and 
apparently not perforated. The visceral chambers of the corallites are occupied by large 
tabule that are rather closely set, and in general almost horizontal, but somewhat 
irregular. The space between the corallites is filled up with vertical canalicule: formed by 
the costa that are well developed, and are subdivided by horizontal or slightly convex 
dissepiments into cells of about one fifth of a line broad. 
Upper Silurian deposits at Dudley, Walsall, and Delves Green. Professor M‘Coy 
mentions its existence in the Coniston limestone of Sunny Brow near Coniston, Lancashire ; 
in the impure limestone of Golugoed, Mendinam, Caermarthenshire ; and at Egool and 
Bellaghaderreen, Mayo. 
Specimens are in the Collections of Mr. Fletcher and Mr. J. Gray, of Dudley; of the 
Geological Society, the Parisian Museum, &c. 
P. petaliformis much resembles P. follis, but in this last-mentioned species the calices 
are smaller and more closely set, and the general form of the corallum appears to be 
constantly different. P. sc/fa’ is much smaller than P. petaliformis, and its septo-costal 
radii are much more regular. 
2. Puasmopora scita. ‘Tab. LIX, figs. 2, 2a. 
Puasmopora scita, Milne Edwards and Jules Haime, Polyp. Foss. des Terr Paleeoz. (Arch. 
du Mus., vol. v), p. 222, 1851. 
Corallum free; basal surface slightly convex, with a lamellated and somewhat 
prominent edge, and covered with a strong, wrinkled epitheca. Calices equally developed, 
shallow, quite circular, with a thin, shghtly prominent edge, and set at a distance from 
each other that does not exceed their diameter. Coste slender, smooth laterally, set wide 
apart, in direct continuation with the septa, and always joing directly the corresponding 
ones of the neighbouring corallites, but often united together at their outer edge by a small 
transverse lamina, which closes up exteriorly the intercostal loculi. Sep/a 12, almost 
1 Milne Edwards and J. Haime, Polyp. Foss. des Terr. Palaoz., p. 223, pl. xvi, fig. 3. 
2 See tab. lix, fig. 2. 
