FOSSIL ALCYDNIA* 4$ 



belonging to a former world. So great indeed will be the 

 variety of these bodies, and so perfectly well preserved 

 will they appear, as to render it necessary for me to say a 

 few words, respecting the state of preservation in which 

 they are found. 



This is rendered necessary; since the comparatively fre- Attempt to ac. 

 quent appearance of these bodies, in a fossil state, appears count l ** 

 to contradict a position laid down in the former volume* 

 whilst speaking of fruits, that substances possessing a pulpy 

 consistence were not likely to be found in a fossil state; 

 since their decomposition would most probably take place 

 with too much rapidity, to allow of that change being ef- 

 fected, on which their mineralization would depend. But 

 a peculiarity of structure exists in these animals, which 

 exempts them from the influence of this law. It appears, 

 as we have seen from the observations of Marsilli and Do- 

 nati, that these animals have blended, with their gelatinous 

 and carneous substance, innumerable minute spicula?, which 

 may be considered as the bones of the animal. These ma- 

 nifest themselves by the prickling sensation they occasion, 

 on being handled, which has obtained for some of these 

 animals the name of the sea nettle. That these spiculie, 

 formed of a hard and durable matter, may, in some, and 

 especially that the spongy fibres and coriaceous covering 

 may, in others, keep up the form of the animal, for a suf- 

 ficient time to admit of the petrifactive process being ac- 

 complished, seems to be not improbable; and indeed ap- 

 pears to afford a satisfactory mode of explaining this curious 

 fact. 



That the bodies now about to be more particularly de- They must • 



scribed are the remains of animals of a former world, seems have belonged 



. to a former 



to require no stronger proof, than the circumstance of these WO rld. 



inhabitants of the sea being found in their changed state, 



in mountains much elevated above the level of the sea, and 



at a considerable distance from the situations which it now 



possesses. Whilst treating of the fossil corals, many were 



pointed out, whose recent analogues were positively not as 



yet known, and which were therefore conjectured to be the 



remains of certain species which might be now extinct. .Any 



opinion of this kind with respect to these animals appears 



to- 



