ANIMALS. 37 
than usual, and their lower part, on the celluliferous surface, is strongly angulated 
through the prominency of the dividing ridge, and the close proximity of the tubercles ; 
while higher up they possess the usual characters. Similar differences obtain with 
the meshes, the form of which depends chiefly on the distance of the stems from each 
other, being circular in one specimen, oval in another, oblong in this, and linear in that. 
The fossil represented by Goldfuss in the ‘ Petrefacta Germaniz,’ pl. xxxvi, fig. 2 4, ¢, 
is a rare condition for this species. I have been fortunate, however, in obtaining a 
specimen resembling it, showing the tubercles with an aperture at the apex, as repre- 
sented in Plate II, fig. 11. Never having been able to find any internal casts of 
these appendages, so frequent as regards the cellules, I am inclined to think that they 
remained closed until a late period of their growth. Mr. Lonsdale, referring to 
Goldfuss’s figure, simply designates them “abraded vesicles.”" Why may they not 
be considered gemmuliferous vesicles, which have become ruptured through the 
discharge of their contents? M‘Coy’s Fenestella carinata, and some other species, 
display similar open cellules.* 
This Coral sometimes attains a large size: the frond of my largest specimen 
measures eight inches in width. The under side or non-celluliferous face is occasionally 
seen with root-like processes, apparently hollow, from} to ; of an inch in length, 
striking off from the stems (vide Plate II, figs. 18 and 19). . From what is displayed 
in a specimen before me, I am inclined to think that in many cases all the fronds of 
one Coral possess these processes, and that they served, not only as supports to the 
fronds, but as stays to keep them separated from each other. Specimens are some- 
times so completely folded, that it is difficult to abandon the idea of its being the outer 
surface of the frond, which is celluliferous. Is not the specimen represented by Geinitz, 
in his ‘ Versteinerungen,’ pl. vii, fig. 15, in this condition ? 
Mr. Lonsdale, in showing that Fenestel/a has no relation to Gorgonia, the genus in 
which Goldfuss and others have placed the Permian Corals, states, that ‘“ beneath the 
thick series of obliquely-overlying cylindrical cells, limited to one side of the Coral, 
there is no axis formed of concentric bands, yet distinct from the crust,” as in Gorgonia, 
“but a parallel layer of vertical, capillary tubes, the walls of which differ not 
apparently from those of the cells. In the young state this layer constitutes the outer 
surface of the non-cellular side.” In Fezestella retiformis the vertical capillary tubes 
are sometimes finely displayed, when they are seen to be straight, and crowded with 
minute foramina, as shown in the magnified representation in Plate II, fig. 17. 
According to Mr. Lonsdale, the intermediate layer of vertical capillary tubes is totally 
wanting in Retepora (Hlasmopora), proving that the species under consideration does 
not belong to this genus, as was formerly supposed. 
' Geology of Russia, &c., vol. i, Appendix A, p. 630. 
? Synopsis of the Carboniferous Fossils of Ireland, pl. xxviii, fig. 12; pl. xxix, figs. 1, 2. 
% Geology of Russia, vol. i, Appendix A, p. 627. 
