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



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 lime- 

 stone were the chief repositories. I traced them upwards into the 

 cher^ ; 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 cylin- 

 ders 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 sand- 

 stone, 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.* 



Since my return to London, the drawings and specimens 

 above described have been seen by several gentlemen skilled in or- 

 ganic 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 ditTerent species, not one of which had hitherto 

 been described. The circumstances which he pointed out in v/hich 

 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. 



* In a subsequent excursion to Dorsetshire, I observed evident traces of an alcyonium 

 nearly similar in the Purbeck stone, and anotl-.er apparently somewhat difTerent in the 

 limestone rocks between Weymouth and Sandsfoot Castle. I found in great abundance 

 the appearances of the ^v'hite radiated circular and elliptical figures in the Isle of Port- 

 land, and have since noticed that these arc 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-wa^ s of most of tlic large houses in this metropolis. 



Vol. II. 3 c 



