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fossils, Mr. Bowman is convinced that they stand where they origin- 
ally flourished; that they were not succulent, but dicotyledonous, 
hard-wooded forest trees; and that their gigantic roots were mani- 
festly adapted for taking firm hold of the soil, and in conjunction 
with the swollen base of the trunks to support a solid tree of large 
dimensions with a spreading top. 
Towards the close of 1838, in forming the railway tunnel at Clay- 
cross, five miles south of Chesterfield, a number of fossil trees were 
found, standing at right angles to the plane of the strata. The tunnel 
passes through the middle portion of the Derbyshire coal measures, 
which there dip about 8° to a little north of east. The bases of the 
trees rested upon a seam of coal fifteen inches thick. ‘The exterior 
of the stems consisted of a thin film of bright coal, furrowed and 
marked like the Stgillaria reniformis ; and the interior consisted of a 
fine-grained sandstone. Mr. Conway, who supplied Mr. Bowman 
with an account of the discovery, infers, from the information which 
he obtained, that there must have been at least forty trees found, 
and judging by the area excavated, he is of opinion that they could 
not have stood more than three or four feet apart. ‘There were no 
traces of roots, the stems disappearing at the point of contact with 
the coal. Several specimens of Stigmaria ficoides were also noticed 
by Mr. Conway, lying horizontally and about three feet in length. 
With reference to fossil trees in general, and especially to those 
near Manchester, Mr. Bowman proceeds to show still further; Ist, 
that they were solid, hard-wooded, timber trees, in opposition to the 
common opinion that they were soft or hollow; 2nd, that they ori- 
ginally grew and died where they have been found, and consequently 
were not drifted from distant lands ; and, 3rd, that they became hol- 
low, by the decay of their wood, from natural causes, similar to those 
still in operation in tropical climates, and were afterwards filled with 
inorganic matter, precipitated from water. 
1. In’stating his reasons for believing that the coal measures’ casts 
were solid timber trees, Mr. Bowman alludes to the rifting of the 
bark of modern forest trees, in consequence of the expansion caused 
by the annual addition of a layer of wood between the bark and the 
alburnum ; and to the thickening or swelling of the base of the trunk 
and main roots, and the apparent lifting up of the latter out of the 
soil, in old trees, by the greater annual increase of the upper part or 
that nearest to light and heat. These phenomena in vegetation were 
illustrated by a diagram, which exhibited the form of the base of the 
stem and the root of a sapling, and of a full-grown tree. The author, 
in applying these characters to the fossils of the Manchester and 
Bolton railway, alludes to the irregular, longitudinal and disconti- 
nuous or anastomosing furrows on their surface, to the swelling out at 
the base of their stems, and to the divergence as well as the angle 
of dip or downward direction of their roots. These characters, he 
says, are not observable in soft monocotyledonous trees, their stems 
never expanding laterally, and being as thick when only a few years 
old and a foot high, as when they attain the height of 60 or 100 feet. 
Their roots also, instead of being massive and forking, generally pre- 
