98 



cular. To know the animals that are thus found as it were 

 petrified may not seem at all the province of the minera- 

 logist, nor is it perhaps strictly necessary; yet it is conve- 

 nient to have such information, as it may be sometimes of 

 great importance; and it must appear remarkable to all, that 

 although the petrified remains of other animals are very uni- 

 versal, yet those of our own species are never found. The 

 effects of the change in the Echinus are remarkable, as it 

 appears to be extremely gentle; for the parts of the shells 

 which are of a delicate structure, and are easily separated in 

 common decay, are often very little disturbed by the changes 

 of the animal substance. The animal parts, exclusive of 

 the Carbonate of Lime, must pass away, while Carbonate 

 of Lime, or Flint, is filling up the vacancy. 



This species of Echinus is either a new one, or a variety 

 of Echinus Cidaris of British Miscellany , and was sent to 

 me from Queen sford by my kind friend T. Mead r Esq. 

 The soil in which it was found is a chalky marie. 



TAB. CLIL 



I he apparent loss of the animals in these Echini is as yet 

 unaccounted for, and an immense quantity must have been 

 lost to our view; although, on the examination or analysis 

 of Earths, the animal substances have never been discovered. 

 Mineralogists have indeed lately discovered alkali in some 

 Basalts, See. which was always supposed to belong to the 

 vegetable kingdom. This specimen was found in a chalky 



