OCCURRING IN THE VARIOUS STRATA. 9 



find it difficult to trace the operation of any sweeping current. By at- 

 tending to the manner in which the leaves and branches in recent planta- 

 tions or forests are found annually at the fall of the leaf, lying indiscri- 

 minately in every direction, much of the difficutly arising from the alleged 

 confusion may be got over, as it can be accounted for by the simple opera- 

 tion of violent winds. 



If we take it for granted that the coal-seams are formed by the deposi- 

 tion of vegetable matter, produced either on the spot where it is now found, 

 or brought from a distance, we can easily offer an explanation for the dif- 

 ferences found to exist between the coal-fields of England above alluded 

 to and the Scotch basins, in regard to the occurrence of fossil vascular 

 cryptogamic plants, and their impressions. In a flat country, like North- 

 umberland, Durham, and Yorkshire, surrounded by mountains of no great 

 elevation, from which a supply of more perfect wood could have been ob- 

 tained, the vast mass of carbonaceous matter deposited must have resulted 

 from vegetables growing on the spot, and this may have had its origin in 

 a great measure from the vascular cryptogamic plants, which a marshy 

 country, such as it might have been, would have produced in great abun- 

 dance, and with a luxuriance of which we can now have but little concep- 

 tion, unless we contemplate the profuse vegetation of the Tropics. 



The Scotch coal-basins on the contrary, seem to have been formed in 

 large inland lakes or hollows, produced by the expansion of immense bodies 

 of water. In these lakes or hollows, the produce of vast forests, which 

 may have existed in the valleys of the high regions, may have been car- 

 ried down by eddies and currents. As these trees had grown at great ele- 

 vations, most of those carried along by the great rivers and their tribu- 

 tary streams may have consisted of Coniferse, or plants possessing a struc- 

 ture closely allied to that of our present pines. 



In coal-fields, in which the carbonaceous strata were formed from such 

 materials, it is not at all surprising that fossils of a vascular cryptogamic 

 character should be considered as rarities ; and although, as stated above, 

 many beds of the Newcastle, Durham, and Yorkshire fields are accompa- 

 nied by varieties of these impressions, yet I believe a considerable number 



