On the scar are three prints, the central one alone representing the vascular bundle, while the lateral prints (parichnos) mark the position of merely parenchymatous strands.
The cortex, often sharply differentiated into sclerotic and parenchymatous zones, is bordered externally by the persistent leaf-bases.
In structure it is equally simple, being composed of parenchymatous tissue without any clearly marked conducting system.
A, The main anatomical features of a cycad stern a Spermatozoids may be summarized as follows: the centre is from G of fi occupied by a large parenchymatous pith traversed g; by numerous secretory canals, and in some genera c p onen-grain by cauline vascular bundles (e.g.
The pith is encircled by a cylinder of secondary wood, consisting of single or multiple radial rows of tracheids separated by broad medullary rays composed of large parenchymatous cells; the tracheids bear numerous bordered FIG.