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section of coal, and he also exhibited various pieces of coal, one 
of which he held in the position it occupied in the coal bed. 
Another diagram, he said, represented a quantity of black coaly 
matter arranged in layers, and embedded in this matter were 
some small bodies which had been flattened by the pressure of 
the coal, and by the superimposed beds between the coal. ] 
Prof. Huxley spoke of these bodies under the name of sporangia, 
or spore cases. Now, he (Prof. Williamson) had come to the 
conclusion that they were all spores of two classes—the larger 
ones called macro-spores, and the smaller ones micro-spores. 
A latge number of the plants, if not all, found in the coal- 
measures belonged to the cryptogamic plants, in which was 
found no trace of seeds or flowers. The reproductive bodies 
that took the place of seeds were little bud-like structures, to 
which the name of spores was given. Ina certain class of those 
plants, the club-mosses, for instance, were two kinds of these 
spores. The sporangia of club mosses and similar plants never 
became detached from their parent stem. They burst and libe- 
rated multitudes of contained spores, which were objects like those 
so abundant in many coals. But these spores did not play so im- 
portant a part in the formation of coal as Prof. Huxley supposed. 
On examining these objects it was found that each of the 
little rounded discs exhibited three ridges that radiated ina 
triangular manner from a common centre, These discs were 
originally masses of protoplasm, lodged within a mother-cell. 
By-and-by each of these masses broke up into three or four 
parts ; and it was found that to accommodate one another in the 
interior of their circular chamber, they mutually pressed one 
another. To illustrate the mutual compression, Prof. William- 
son produced a turnip, which he had cut into four parts, that 
corresponded exactly, he said, in tveir arrangement with the 
arrangement of the four spores in the interior of the mother 
cell, 
Then Prof. Huxley held that coal consisted of two elements. 
Prof. Williamson, exhibiting again a piece of coal said the dirty 
blackening surface was a thin layer of little fragments of woody 
structures, vegetable tissues of various kinds, known by the 
name of mineral charcoal. These layers of mineral charcoal 
were exceedingly numerous. Prof. Huxley, recognising the 
abundance and significance of these little spore-like bodies, 
thought that mineral charcoal forméd only a portion, and a 
limited portion, while the great bulk of black coaly matter was 
really a mass of carbon derived from chemically altered spores. 
He thought that on this point they would be obliged somewhat 
to differ from Prof. Huxley. 
The bed which had been most widely quoted as containing 
most beautiful spores was found in the district of Bradford. If 
everything decayed, and Bradford was by an exceedingly im- 
probable combination of circumstances to pass out of memory, it 
would be remembered in scientific history as the locality in which 
the ‘‘better bed” was found. The fragment he held in his 
hand was a fragment of the better bed. On examining it for a 
moment through a magnifying glass he saw that it was a solid 
mass of mineral charcoal, yet the microscope revealed in it no 
trace whatever of organic structure. Therefore, while Prof. 
Huxley divided coal into two elements—mineral charcoal and 
coal proper, including in the latter term altered spores—he 
would say that coal consisted of three elements—mineral char- 
coal, black coal derived from mineral charcoal, and spores. 
This outline of the history of coal led them to the independent 
conclusion that two elements were mingled in coal ; the vegetable 
déris, or broken up fragments of the plants of the carboniferous 
age were intermingled with the peculiar spores to which Prof. 
Huxley had so properly called attention. In proceeding to deal 
further with the plants of which coal was formed, the lecturer took 
occasion to acknowledge with thanks the loan of certain valuable 
specimens to illustrate his discourse from the Bradford Museum. 
One of these specimens was a most rare and valuable specimen 
which he would be glad to take away with him to Owens 
College, if he had the chance ; but he was afraid the Bradford 
people were too Conservative to stand that. 
After giving a number of botanical and other details with 
regard to the plants of which coal was formed, he said our 
knowledge of this subject resolved itself into two diyisions, viz., 
that of the outward forms of plants and that of their inward 
organisation. These two lines of inquiry did not always run 
parallel, and the one great object of recent research had 
been to make them do so. Specimens throwing light on 
the subject had been found at Arran, Burntisland, Oldham, 
Halifax, Autun in France, and elsewhere, and upon these a host 
of observers had been and still were working, It had long been 
known that most, if not all, the coal plants belonged to two 
classes, known as the Cryptogamia, or flowerless plants, and 
the gymnospermous exogens, represented by the pines and firs. 
All recent inquiries added fresh strength to this conclusion. One 
of the most important of these groups was that of the Equiseta 
or horse tails, and which were represented in the coal by the 
Calamites. The long cylindrical stems, with their transverse 
joints and longitudinal grooves, were shown to be casts of mud or 
sand, occupying the hollows in the piths of the living plants. 
Each of these piths was surrounded by a thick zone of wood, 
which again was invested by an equally thick layer of bark. 
Specimens were shown in which, though the pith was only an 
inch in diameter, the wood and bark combined formed a cylinder 
4 inches thick, giving a circumference of at least 27 inches to 
the living stem, But there exist examples of the pith casts 
alone, which are between 2 and 3 feet in diameter. It was 
evident, therefore, he concluded, that the Calamites became true 
forest trees, very different from their living representatives —the 
horse tails of our ponds and marshes. 
After describing the organisation of these plants, the Professor 
proceeded to describe the Lycopods of the coal measures as 
represented by the Lepidodendra, Sigillarise, and a host of other 
well-known plants. The living Lycopods, whether seen at home 
or in tropical forests, are dwarf herbaceous plants, but in the 
carboniferous age they became lofty forest trees, 100 feet high, 
and ten or twelve feet in circumference. To enable such lofty 
stems, with their dense mass of serial branches and foliage, to 
obtain nutrition, an organisation was given to them approach- 
ing more nearly to that of our living forest trees than to that 
of any recent cryptogams. A succession of woody layers was 
added to the exterior of those previously existing ; so that as 
the plant rose into the air the stem became strengthened by these 
successive additions to the vascular tissue. As this process ad- 
vanced it was accompanied by other changes, producing a large 
central pith, and two independent vascular rings immediately 
surrounding the pith, and the relations of these various parts to 
the roots, and leaves, as well as to the nutrition of the plants, 
was pointed out. The fruits of these Lycopods were then 
examined. The existence of two classes of spores corresponding 
in functions to the stamens and pistils of flowering plants, was 
dwelt upon, and one of these classes (the macrospores) was 
shown to be so similar to the small objects found in coal, as to 
leave no doubt that those objects were derived from the lepido- 
dendroid and sigillarian trees which constituted the large portion 
of the forest vegetation. 
Certain plants known as _ Asterophyllites were next 
examined. The ferns were also reviewed, and shown to be as 
remarkable for the absence of exogenous growth from their 
stems as the Calamites and Lycopods were for its conspicuous 
presence. The structure of some stems supposed to represent 
palms was shown to be that of a fern, there being no true evi- 
dence that palms existed in that age, The plants known as 
coniferous plants, allied to pines and firs, were described, and 
their peculiar fruits, so common at Peel, in Lancashire, were 
explained, and some plants of unknown affinities, but beautiful 
organisation, were referred to. The physiological differences 
between these extinct ferns, and other plants especially in their 
marvellous guvasi-exogenous organisation, was pointed out, and 
the lecturer concluded by showing how unvarying must have 
been the green hue of the carboniferous forests, owing to the 
entire absence from them of all the gay colours of the flowering 
plants which form so conspicuous a feature in the modern Jand- 
scape, especially in the temperate and colder regions, The an- 
tiquity of the mummy, he added, was as nothing compared with 
the countless ages that had rolled by since these plants lived, and 
yet they must not forget that every one of those plants, living in 
ages so incalculably remote, had a history, an individuality as 
distinct and definite as our own. ‘They would probably be 
inclined to ask the question, When did all these things take 
place? Echo answered, When? 
THE BRITISH ASSOCIATION 
HE Bradford Meeting has been on the whole a 
good one; though there have been no salient dis- 
cussions, the papers read have been all up to a good 
useful average. Mr. Ferrier’s paper on the brain 
was a surprise to many, we believe, and the only ap- 
proach to a genuine sensation was the appearance of 
Captain Markham, R.N., in the Geographical Section 
FON ea re ea 
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