384 Mr. Webster on some new Varieties of Fossil Alcyonia, 



marine and animated forest ; and from the Infinite variety of 

 curvilinear forms in which the branches are found, it is probable 

 that they were possessed of the power of moving their arms in 

 every possible direction, for the purpose of searching for and ob- 

 taining their food, which they extracted from the sea-water. 



But if we reflect upon the changes which these extraordinary 

 creatures have undergone, our wonder must increase. From some 

 mysterious cause the animal membrane becomes converted into si- 

 liceous matter ; and we have then to contemplate the idea of their 

 still retaining their original forms and situations but changed into 

 stone. By subsequent convulsions of nature the silicified animals 

 are broken to pieces, whilst the fragments are scattered in all di- 

 rections. These are enveloped and covered by sand and calcareous 

 matter, the alternate depositions of each with these fossils forming 

 the vast mass of strata we have been examining. Had the animals 

 been overwhelmed by the sand while in their living state, they 

 must have been crushed quite flat by the superincumbent weight ; 

 but in no instance is this the case ; their cylindrical forms remain 

 perfect, and do not appear to have suffered from pressure. 



You will no doubt perceive that in thus supposing the first change 

 of the animal into silex, I have followed the theory of Mr. Par- 

 kinson, as stated in his work on organic remains ; and the above 

 observations may perhaps tend to confirm the justice of his con- 

 clusions. That these fossils contain generally more siliceous matter 

 than the investing stone, appears probable from their greater dura- 

 bility, and indeed in some instances I found them almost wholly 

 siliceous. 



Having noticed the extensive distribution of this fossil, I en- 

 deavoured to ascertain the several strata in which it is found. In 

 the ferruginous sand, below the green sandstone, I could not find 



