PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 59 
The List of Donations to the Library was read. 
The following communications were read :— 
1. “On the Structure and Formation of Coal.” By E. Wethered 
Kisq., F.G.S., F.C.S. 
[ Abstract. | 
The author, having referred to the work of previous investigators, 
pointed out that seams of coal do not always occur in one bed, but 
are divided by distinct partings, some of which, as in the case of the 
Durham main seam, contain Stigmarie. It is important to 
notice this feature for several reasons, but especially as the beds of 
coal, defined by the partings, show differences both in quality and 
structure. In the case of the shallow seam of Cannock Chase there 
is at the top a bed of coal 1 foot 10 inches thick, the brown layers 
of which are made up of macrospores and microspores. ‘The bright 
layers are of similar construction, except that wood-tissue some- 
times appears, also a brown structureless material, which the 
author looked upon as bitumen. He, however, objected to that 
term, and thought that “ hydrocarbonaceous substance” would be 
preferable. What this hydrocarbonaceous material originated from 
is a question for investigation. In the lower bed of the Welsh 
“Four Feet” seam wood-tissue undoubtedly contributes to it; 
whether spores do is uncertain; it is true they can be de- 
tected in it. In the second bed of the shallow seam there is a 
very different coal from the upper one. It is made up almost as 
a whole of hydrocarbonaceous material. Very few spores can be 
detected in it. It is possible that the scarcity of these objects may 
be due to decomposition ; but the author’s investigations seem to 
show that spores resist decomposing influences more effectually 
than wood-tissue, which seems to account for the fact that where 
they occur they stand out in bold relief against the other material 
composing the coal. Below the central bed of the shallow seam 
comes the main division. In it the author detected a large accumu- 
lation of spores, but hydrocarbon formed a fair proportion of the mass. 
The author referred to other seams of coal from various parts of 
England, and pointed out the structure of each bed composing them. 
The conclusions on the evidence elicited from his investigations were 
(1) that some coals were practically made up of spores, others were 
not, these variations often occurring in beds of the same seam ; (2) 
that the so-called bituminous coals were largely made up of the sub- 
stance which the author termed hydrocarbon, to which wood-tissue 
undoubtedly contributed. 
An appendix to the paper, written by Prof. Harker, Professor of 
Botany and Geology at the Royal Agricultural College, Cirencester, 
dealt with the determination of the spores seen in Mr. Wethered’s 
microscopic sections. ‘Taking the macrospores, the resemblance to 
those of Jsoétes could not fail to strike the botanist. He had pro- 
cured some herbarium specimens of Jsoétes lacustris in fruit, and 
VOL, XL. g 
