ON A SUBMARINE FOREST IN THE FRITH OF TAY. 429 



of rushes. No provision in these cases had been made for 

 the effect of subsidence. 



Before concluding this paper, I may take notice of a few 

 facts which seem to have some interest in a geological point 

 of view. 



1. One effect of the subsidence to which I have here alluded, 

 is the complanation of all the vegetable remains which oc- 

 cur in a horizontal position, or parallel with the surface of the 

 bed of peat ; while those situate vertically retain their cylin- 

 drical shape. The vegetable remains, so common in the 

 strata accompanying coal in this country, exhibit the same 

 appearances in similar circumstances, and lead to the con- 

 clusion, that the matter of the strata, at the period of depo- 

 sition, was in such a condition as to admit of the mechanical 

 effects of subsidence taking place. 



2. In the examination of the vegetable remains in this bed 

 of peat, and of others which have been investigated, I have 

 been led to conclude (contrary to the commonly received opi- 

 nion*), that many of the supposed stems of reeds which 

 occur in a petrified state, are in fact roots. These roots, or 

 rather subterranean stems, such as the Arundo colorata and 

 phragmites, Menyanthes trifoliata, and many other marsh 

 plants exhibit, frequently occur in beds of peat, in a dead 

 state, and exhibit their peculiar characters, when but few 

 traces of the stems to which they belonged can be detect- 

 ed. 



3. Several 



* See Parkinson's Organic Remains, vol. i. p. 455. 



