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been obtained ; and here its remains are so plentiful, that, in several 

 parts, the buildings are formed of a stone almost entirely composed 

 of its vertebras. But specimens of the body part of the skeleton, espe- 

 cially those with any part of the vertebral column attached, are now 

 exceedingly rare, which is not to be wondered at, when it is consi- 

 dered with what avidity they have been sought ; and that the finer 

 specimens, those which have had one side free from the matrix, must 

 have almost, of necessity, laid near to the surface of the rock, ex- 

 posed to the search of collectors. The matrix in which these remains 

 are found appear constantly to be limestone, and the organic remains 

 themselves are always spathose : but, perhaps, from the deficient 

 proportion of the crystalline matter, interposed between the animal 

 remains, the stone does not, on polishing, yield an appearance suffi- 

 ciently beautiful to occasion its being employed for ornamental pur- 

 poses. 



