 Corner of Coleus Stem stained with Phloroglucinol. The Phloem has not stained but the Xylem, and Phloem Fibers have stained positively for lignin. The dark layer in the Cortex is Chlorenchyma. |
 Same as above but viewed with crossed Polarizers. Note the Collenchyma which was invisible with bright-field optics. |
