264 THE MEDALS OF CREATION. Cua. VII. — 
5 
In the tertiary clays at Bracklesham Bay, Sussex, a beau- 
é 
tifal small coral of this type (Siderastrea Websteri, Dixon’s — 
Foss. tab. i. 5), is found attached to flint pebbles. 
Several species of this and the following genus, perfectly © 
silicified, are found in the state of pebbles and boulders in 
the superficial soil of Antigua, and other islands of the West — 
Indies, associated with the fossil palms, described in a former 
part of this work. Some of these corals are of great beauty, 
and polished sections exhibit the coralline structure most 
perfectly.* 
Maprepora.— Polyparium arborescent or frondescent, 
porous, fixed ; cells deep, with twelve rays, prominent, irre- 
gularly dispersed on the surface, and accumulated towards 
the terminations of the coral. 
The term madreporite, or fossil madrepore, was formerly 
applied to all the branched fossil corals with radiated cells, 
but is now restricted to those which possess the above cha- 
racters. The recent common species, figured Wond. p. 620, 
will serve to illustrate this genus. The elevated, branched 
Madrepores, with minute polygonal cells having twelve rays, 
the lamelle of which are denticulated, are termed Porites, 
and are frequent in the Silurian strata (Sv. Syst.). 
Mituepora. Lign. 89.—Coral ramose ; cells very minute, 
distinct, perpendicular to the surface, giving the interior a 
finely striated fracture, disposed irregularly. 
There are many fossil species of this genus, some of which 
are of considerable size. A small species from the moun- 
tain limestone is figured Lign. 89, fig. 7.T 
LirgopEnpron. Lign. 70, jig. 3.—Polyparium branched, 
formed of deep, cylindrical, elongated cells, which are ter- 
minal, and radiated, with a prominent central axis. 
Large masses of corals of this genus, composed of clusters 
* In the “ Spongitenkalk,” at Nattheim, near Heidenheim, all the 
corals are replaced by chalcedony. 
¢ Millepora, Pict. Atlas, pl. xl. fig. 6. 
