46 FOSSIL ALCYONIA. 



to be hardly admissible; since from the innumerable re- 

 cesses in which they lurk, and still more from the compara- 

 tively small degree of eagerness with which they have been 

 sought, we are totally unable to form any conjecture, as to 

 the number of those which may have hitherto entirely es-^ 

 caped observation. Analogy indeed may lead us to con- 

 clude, that by far the greater part of these fossil bodies are 

 actually the remains of extinct species; but where evidence 

 of a stronger kind cannot be also obtained, the fact must be 

 considered as undetermined. 



Fossil alcyonia Having made these few prefatory remarks, I shall now 

 proceed to a more particular examination of such fossils of 

 this description, in my possession, as are most illustrative of 

 the history of these extraordinary animals. 



Ramified. Those which are of a ramified form s.em to be most 



rarely found in a mineralized state. The specimen however 

 which is figured, Plate VII, fig. 12*, and which was found 

 in Berkshire, is undoubtedly the fossil remains of one of 

 these species ; although it is impossible to say to what par- 

 ticular ramified species it belongs, or whether indeed it is 

 at all referable to any known species. 



Silex & chalk. An examination of the substance of this fossil, now a 

 mixture of silex and carbonate of lime, affords us internal 

 evidence of its origin ; since its texture is such, as I have 

 found almost constantly to characterise the fossil remains of 

 any individual of this genus, which had been composed of 

 a sponge-like substance. This substance has evidently, like 

 sponge, been of a reticular texture ; but the disposition of 

 the meshes, if so they may be called, is in the spongy al- 

 cyonium much more uniform .and determinate than in ordi- 

 nary sponge, and though not to be described iu words, the 

 texture is so peculiar and characteristic, as directly to be 

 known by those, who have been in the habit of examining 

 these and similar substances, by the aid of magnifying 

 glasses. 



Digitated. The fossil represented Plate VII, fig. G, and which is also 



from Berkshire, appears to bear a tolerably close resem-» 



* The references here and elsewhere are to the figures of the original 

 work. 



blance 



