Mistletoe (Viscum album) stem. Light micrograph of a section through a stem from a European mistletoe plant. The epidermis has a thick cuticle (yellow) with scattered stomata (pores). Under the epidermis are collenchyma cells, the inner cortex and parenchyma cells containing chloroplasts (green) and starch grains. Then there is an inner ring of nine vascular bundles consisting of sclerenchyma (brown), first-year phloem sieve tube cells and parenchyma, then the cambium, second-year xylem ad first-year metaxylem. At centre of the stem is the pith composed of parenchyma cells. Magnification: x7 when printed 10 centimetres wide.