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is directly opposed to the generally received definition of a root, 
i.e. " That its fibres obey no fixed order of arrangement ;" 
and, secondly, the apparent indications of articulate or mov- 
able fibrillae, if such has been the case, is, I believe, without a 
parallel. From a fine example discovered at Dukinfield, 
Mr. Binney has also determined a singular character in this 
plant, which has long presented a difficulty I could not 
solve ; — that the upper portion of the stem, probably all that 
was above the surface of the ground, had the perpendicular 
parallel lines which characterise Sigillaria. The lower portion 
of the stem beneath the soil, and the main radicular branches 
extending to the secondary and tertiary bifurcations, a 
gnarled, and ruggedly striated appearance ; and, finally, the 
terminating radiculae, the quincuncial areolae, and fibrillae of 
the Stigmaria. There is yet, however, another point to 
determine. What was the nature of the extremities of the 
radiculae ? As amongst the hundreds of specimens that have 
passed under my observation, I have never seen one with the 
terminal portion. It is, therefore, an interesting point to 
ascertain whether this also differs in character from the 
other parts of the plant. 
My attention has been called to this question by having 
recently obtained, from a sandstone quarry, near Leeds, the 
terminal portion of a plant possessing well-marked and 
peculiar characters, somewhat resembling those of Stigmaria 
at first sight, but, when closely examined, apparently distinct. 
The specimen to which I allude is smaller than I have ever 
seen any of the Stigmaria, being only about two inches in 
diameter. In the smaller and more perfect specimens of the 
latter, the circular scars, as I have already observed, are 
generally arranged in quincuncial order, though varying 
much in the distance at which they are placed from each 
other; but without any connecting lines. In the specimen 
recently obtained, its first peculiarity consists in having a 
