Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/250

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Additional Note by Mr. Parkinson.

The specimens Nos. 1. and 4. illustrate the nature of some fossil corals, showing that the forms in which they at present exist are not those which belonged to the same substances in their original state, and consequently ought not to affect their specific or generic distinctions.

In some of these specimens only circular or polygonal cavities occur, which possess no internal radiated structure, but have their insides more or less crenelated. Dr. Skey's specimen No. 4, is chiefly composed of empty cylindrical cavities with slightly crenulated sides; but in two of these cavities, near the center of the specimen, erect lamellæ are disposed in a stellular form, evincing that the corresponding lamellar of the other cavities have been removed by accident.

In other specimens are erect radiating lamellæ not surrounded by any parietes. Dr. Skey's specimen No. 1. is also thus composed of lamellæ forming stellular columns, between which no parietes are disposed. But in one part of this specimen the compleat form of the madrepore appears, two or three of the radiated columns being here surrounded by similar parietes with those which are seen without any columnar portion in specimen No. 4, showing that this was the original form of the madrepore, and proving the identity of the madrepore an remains in both Dr. Skey's specimens, Nos. 1.and 4.