Plate P3. Vitrinite showing fluorescence from cell walls. 3. T5809; Hole 1109D; 387.86 mbsf. Oblique section of wood preserved as telovitrinite. The cell lumens are partially filled with humic material, but open lumens are still present and little compaction has occurred. Cell walls are much lower in reflectance and are most easily seen in fluorescence mode. The vertical cells represent a medullary ray structure (reflected light; field width = 0.22 mm; vitrinite reflectance [cell contents] = 0.34%).