Dicranopteris TS rhizome
Although this is a member of
the lower vascular plants, Dicranopteris (Gleicheniaceae)
serves to illustrate how the vascular tissue is arranged
in these plants.
Fern rhizomes have rather complicated anatomy, as illustrated here by Dicranopteris. This fern rhizome has been included, as it is unusual, in that the xylem is composed of xylem vessels (X). These vessels have distinctly perforate end walls. There is a large group of sclerenchyma fibres above the xylem. These serve an important mechanical function, as the rhizome is not distinctively woody, and neither are the fronds which emerge from this structure.
Note the phloem tissue (P) which forms a cross in the centre of this micrograph, and which completely surrounds a parenchymatous field (Par) below.