Carruthers— On a Fossil Cone from the Coal-measures. 435 
sporangium is continuous over the protuberance. These prominences 
are seen in the sporangium fig. A 5, and more marked specimens 
occur in a broken case which I have figured at a6. They are 
strikingly shown in Mr. Prestwich’s illustration. Supposing that 
these might be spores, I had several thin sections of a shale in which 
the sporangia abound prepared ; but I have not been able to discover, 
in the numerous sporangia I have examined, any structure like a spore. 
This, however, undoubtedly arises from the manner in which the 
bodies are preserved. Prof. Morris accurately describes them as 
being ‘neither bituminized nor mineralized, but in a state of brown 
vegetable matter.’ The external form, and even the cell-markings on 
its surface, are beautifully preserved in the mould of shale which was 
deposited around them; but no internal structure exists. A change 
similar to that produced in animal bodies when they are converted 
into adipocere has taken place in them; and they are converted 
into a hydrocarbon of an orange-brown colour when seen by 
a reflected light, and of a texture like solid paraffine. It is remark- 
able that while the axis and scales of the cone are converted into 
coal, the sporangia should be changed into so different a substance : 
and this is the condition in which they appear always to occur. The 
specimens obtained from coal and shale which I have examined, the 
examples from the splint-coal of Fordel described by Prof. Balfour, 
and those from coarse sandstones of Coalbrook Dale, described by 
Prof. Morris, are all in the same condition. Prof. Balfour suggests 
that the organic mineral called by the late Prof. Johnstone, of Dur- 
ham, ‘ Middletonite,’ may be derived from these sporangia. This 
mineral was originally obtained in very thin layers, or in small round 
particles, in the main-coal at Middleton, near Leeds. It occurs so 
abundantly both in layers and in granular pieces in the Fordel coal, 
as to give a peculiar rusty-brown aspect to the coal. This substance 
was observed more than forty years ago by the late Dr. Fleming in the 
‘splint-coal’ of Balbirnie, in Fife, and afterwards in coal from 
Clackmannan; and he believed that certain veins of arich wine-yellow 
which occur in Boghead coal were the same mineral. All the spo- 
rangia which I have had sliced show a perfectly uniform structure 
throughout, and this substance exactly agrees in its physical proper- 
ties with ‘Middletonite’ as described by Johnstone. 
The cavity of the sporangium is filled with a dark amorphous 
substance similar to the body of the rock in which the discs are 
found. Prof. Balfour considers this black carbonaceous matter to be 
the altered sporules, and corresponding to the Lycopode-powder of 
recent Lycopodia. 
Having described this singular fossil, there are two questions that 
we shall examine: first, the relation this cone bears to the different 
specimens of Lepidostrobi that have already been described; and, 
secondly, the affinities it has to the living vegetable kingdom. 
The great majority of specimens of Lepidostrobus are found flat- 
tened and carbonized, and so exhibiting the forms of the cone without 
any structure. Some examples found in nodules in shale are pre- 
served in the round, showing the external form and the arrange- 
FF9 
