1847.| BROWN ON LEPIDODENDRON WITH STIGMARIA ROOTS. 47 
that the stem in question is a genuine Lepidodendron united to roots 
of Stigmaria, 
The main coal, six feet in thickness, is overlaid by a shale roof 
abounding in plants. Occasionally when the coal is worked out, large 
masses of shale fall down, leaving hollow spaces known to the 
miners by the name of “Pot Holes’’ ; the fallen masses being in 
fact the roots and truncated stems of Sigillariz and other trees, 
which separate at the parting formed by the coaly bark covering the 
roots, when the supporting coal is taken away. The pit overman 
having brought me several pieces of the root of a tree from one of 
these pot-holes, showing the areole of Stigmaria scattered amongst 
rhomboidal markings peculiar to Lepidodendron, I caused the timber 
props to be taken out, which allowed the shale roof to fall and bring 
down with it the remaining roots and a piece of the stem of the tree. 
Fig. 1. 
ee 
: =S 
SS Se 
MAIN COAL SEAM. 
Six Feet thick. 
Underclay containing Stigmaria. 
Fig. 1. Section showing the position of the tree above the coal seam, with the 
inclination and lengths of two of the principal roots so far as they could be di- 
-stinetly traced. 
Fig. 2. Sketch of the trunk with its branching roots, constructed from careful 
measurements of the dimensions and position of each root, taken on the spot. 
The stem being composed of friable shale arranged in horizontal 
layers, separated and fell away from the bark when the props were 
removed, leaying a hollow cylinder of coaly matter one-third of an 
