Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/395

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385
Mr. Webster on some new Varieties of Fossil Alcyonia.

any specimens. In the blue marl on which the sandstone rests, I found only two or three fragments of cylinders with the cortical part easily detaching itself, the substance being of the same nature as the stratum containing them. The green sand and the limestone were the chief repositories. I traced them upwards into the chert; but they there became rare, and they totally disappeared in the chalk marl. But in the fragments of flint with which the shore from Dunnose to Ventnor is covered, I found many of the cylinders enclosed, and sometimes exhibiting both the internal and cortical part. Frequently I observed white circles in the flint, somewhat resembling those above-mentioned in the green sandstone, having in the internal part flint of the same kind as the envelope; and it is not improbable that these are sections of the cylindrical forms I have been describing.[1]

Since my return to London, the drawings and specimens above described have been seen by several gentlemen skilled in organic remains, and particularly by Mr. Parkinson. It was his opinion that they all belonged to the genus Alcyonium, but were of three if not four different species, not one of which had hitherto been described. The circumstances which he pointed out in which the first-mentioned differed from any known fossil Alcyonia are the following.

The heads vary in form from any other, being longer or more tulip-shaped.

  1. In a subsequent excursion to Dorsetshire, I observed evident traces of an alcyonium nearly similar in the Purbeck stone, and another apparently somewhat different in the limestone rocks between Weymouth and Sandsfoot Castle. I found in great abundance the appearances of the white radiated circular and elliptical figures in the Isle of Portland, and have since noticed that these are extremely common in the blocks of stone brought from that place to London. They may be seen very distinctly in the Portland slabs in the door-ways of most of the large houses in this metropolis.
Vol. ii.
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