8 . II. RELICS. Phenomena. 



u. In strata holding vegetable reliquia, as well 

 as in those in which the animal occur, the different 

 species are sometimes confusedly mixed or blended 

 together But 



V. It more frequently happens, that the different 

 species are found in distinct or separate accumula- 

 tions. 



B. 4. The phenomena peculiar to petrifactions 

 may thus be stated. 



a. Petrifactions are generally confined to moun- 

 tains, or other elevated situations, where the more 

 ancient of the secondary strata are presented to our 

 view. (v. . III. Soil, &c. ) 



b. They are usually incorporated in the earths 

 and stones, of which these strata consist,ff forming 



separated by seams or very thin strata of calcareous stone, contain- 

 ing echinittK and other marine productions About a mile 

 from Buxton, Derbyshire, on the right of the Macclesfield road, a 

 coal-pit was opened some years back, in which we observed strata 

 of shale and ironstone abounding in impressions of anomitue, &c. 

 although the interceding beds of coal and gritstone exhibited only 

 vegetable petrefactions these can only be considered as partial 

 exceptions, however, to the more usual phenomenon of vegetable 

 fossils and the remains of marine animals occurring in distinct 

 tracts. 



ft The most common exception to this remark, and to the fore- 

 going one, under a., occurs in petrified wood, or woodstone, 

 (Lythoxylpn) which is generally confined to water or modern 

 alluvial tracts, and is mostly found in a loose or unconnected state. 



