, Al g Structural and - Physiolog wcal Botany. 
mud, and their remains preserved in the rock which results 
from the hardening of the mud. The soft and delicate 
parts could not be perpetuated in this manner; and it is 
found in fact that only the harder parts, like the wood, bark, 
ie 
By 
‘ Sex Nye 
= iN (My, Suugnsess ot 
: ee i iy : lh ae oN M , 
i i Mv rey | | y 
I | CH HEL i 
wii i 
whith, 
HA Hil | 
aK Hi Hi 
stems of fossil trees ; 6 bed of ironstone; c layer of shale ; d bed of coal. 
Fic. 534.—Section of coal-measures at St. Etienne; a bed of sandstone with erect 
Si 
ih i 
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and fruits, are preserved (Fig. 534). The softer portions 
have been more or less quickly decomposed ; although, under 
specially favourable conditions, there has been some preser- 
vation even of them. The delicate parts, for example, are — 
