Fig. 5.3-19a and b. Transverse section of stems. It is not very common for epidermis cells to be sclerenchyma, it does occur occasionally. In these, the epidermis cells have deposited a secondary wall and then lignified it. Fig. a (above) is a sedge (Scirpus), and you can see that there are many fiber bundles just below the epidermis as well as between the large intercellular spaces. The vascular bundles too have fibers alongside them.

Fig. b (below) is a rush (Juncus). The high magnification view shows the thick walls of the epidermal cells, virtually indistinguishable from those of the fibers immediately below.