270 
The low and flat tracts in which this destructive operation goes 
on most rapidly, are those in which, from the deep rich soil and 
excessive moisture, all below the tall forest trees and larger palms 
is occupied by canes, bamboos, and minor palms. Such tracts would 
be most easily submerged; and in Mr. Hawkshaw’s opinion they 
might hereafter present a seam of coal, which would afford but few 
distinct traces of palms and forest trees. These phenomena, he says, 
may explain in part, why so few distinct forms remain of the num- 
berless forest trees, which must have formed a portion of the vege- 
table kingdom, at the time of the accumulation of our coal deposits. 
Mr. Hawkshaw does not attempt to explain the process by which 
dicotyledonous trees are rendered hollow in tropical forests. He 
expresses doubts respecting tne probable nature of the Calamites 
of the coal measures, and offers no explanation of the means by 
which they have been preserved in so greatabundance. If the coal 
be considered as the debris of a forest, he says, it is difficult to ac- 
count for not finding more trunks of trees than have been discovered 
in our coal basins; and he observes, it is only perhaps by allowing 
the original of our coal seams to have been a combination of vege- 
table matter, analogous to peat, that the difficulty can be solved. 
In this case, he is of opinion, but a few isolated trees might be ex- 
pected to be found, and that the remains of vegetable forms most 
frequently discovered, would only be confirmative of the antiseptic 
qualities of their original nature, as previously advanced by Professor 
Lindley, and not of the number or importance of their particular 
genera at the time of their deposit. 
In conclusion, Mr. Hawkshaw says, that whatever opinion may 
be drawn from what is conjectural in his paper, it will be obvious, 
that though fossil remains may be found filled with a mechanical 
deposit, and containing traces of other vegetables, yet that this con- 
dition does not prove, that the plants were originally hollow, nor 
even render it the most likely hypothesis, as they may haye been 
hard wood-trees, the centre of which had been removed by natural 
processes, 
A paper was then read, “‘ On the characters of the fossil trees lately 
discovered near Manchester, on the line of the Manchester and 
Bolton railway; and on the formation of Coal by gradual subsidence ;” 
by John Eddowes Bowman, Esq., F.L.S. communicated by the 
President. 
The paper commences with a few preliminary remarks on the 
theory of repeated subsidences of the land during the carboniferous 
zra; and on the drift theory, the author being of opinion that the 
former receives much support from the phznomena presented by 
the fossil trees found near Manchester, and that it affords in return 
great assistance in explaining the peculiarities of their position. 
Mr. Bowman does not deny that plants may have been carried into 
the water from neighbouring lands, as in the instances of fern-fronds 
and other remains scattered through the sandstones and shales ; but 
he conceives it is difficult to understand whence the vast masses of 
