What are the features labeled A-D? Try and identify the plant stems. What
problems are there in identifying these plants? The scale bar = 5mm.
||Geopetal sediment in a plant straw
||A xylem strand displaced during the decay
and shrinkage of the plant stem
||A cemented fracture cutting previously
silicified plant axes and matrix
||Shrunken and partially decayed axes
|| Straws of Aglaophyton major.
||Many anatomical features have been lost prior to
silicification due to the shrinkage and partial to almost complete decay
of the plants. A few clues remain to identify them at the magnification in
this photograph; partly the relatively large diameter of the axes but more
specifically the pattern of cortex decay (bottom left) is primarily found
in Aglaophyton. We cannot tell at this magnification if the xylem
cells lack thickenings.