dtirifig the Deposit of the Transitmi and Coal series. 29 



The internal structure, its singular colour when contrasted 

 with the block of sandstone in which it was found, induced 

 me to request my friend Mr. Nicol to analyse it. The fol- 

 lowing was the result : 



60 per cent of carbonate of lime. 

 18 per cent of oxide of iron. 

 10 per cent of alumine. 

 9 per cent of carbonaceous matter. 

 The height of this gigantic plant was thirty-six feet ; three 

 feet diameter at its base, and lying in nearly horizontal posi- 

 tion corresponding with the dip. No branches were found. 

 This therefore, with a few others I could here mention, and 

 which I trust will ere long be submitted to your considera- 

 tion, form but trifling exceptions to the general distribution 

 of early vegetation. 



Thus in these great coal-fields (exclusive of the many varie- 

 ties of plants found in the bituminous shale, which I am happy 

 to sav will shortly be submitted to the public, in a work in- 

 titled' " The Fossil Flora of Great Britain," by Mr. Lindley, 

 Professor of Botany in the London University, and my friend 

 Mr. Hutton of Newcastle) we find theopinion of M. A. Brong- 

 niart most completely verified; namely, that the vascular cry- 

 ptogamic plants had a vast numerical proportion ; and in fact, 

 of 260 species discovered in this terrain or period, 220 belong 

 to this class. " Should however," adds M. A. Brongniart, 

 " more precise observations or new discoveries make known 

 in the old formation, some plants of more than one of the 

 classes which we have admitted, or even some species of 

 one of the classes which have appeared to us to be wanting at 

 this epoch, still the essential relation of these classes to each 

 other would be but slightly modified. Thus it might be 

 proved, that certain, yet little known genera of the coal for- 

 mation, are true dicotyledonous plants. Yet it would not be 

 the less certain, that the vascular cryptogamic plants were 

 by much the most numerous vegetables, during the first period 

 of vegeiation." The same remarks he makes respecting the 

 lias, and other formations. Thus whatever new discoveries 

 may be made in the vegetables of this period, from the first 

 deposit of the transition rocks to the top of the coal-field, yet 

 the essential characters can be but slightly modified, and this 

 period will always remain perfectly distinct. 



The more gentlemen will therefore interest themselves in 



had so little time for examination, I cannot now give a final, but only a 

 conditional c|.inion. It is, that 1 believe it to be a section of a mono- 

 cotyiedonous plant." 



promoting 



