These concentric rings of secondary xylem and phloem (fig. 9) afford a characteristic cycadean feature.
In some cases he seems to refer to the phloem and cambium by this name, and in other cases to the perimedullary zone.
The central tissue (x) is called the woody tissue (xylem); the outer, the bast (phloem).
The browning in the vascular bundles appeared to be confined to the phloem tissue.
This shows a number of white bars (xylem) surrounded by a more delicate tissue (phloem).
The phloem, when strongly magnified, is seen to be made up of cells arranged in nearly regular radiating rows.
Just inside of the bundle sheath there is a row of similar fibres marking the outer limit of the phloem (ph.).
1870, from German phloëm (1858), coined by German botanist Karl Wilhelm von Nägeli (1817-1891) from Greek phloos, phloios "bark of trees," of uncertain origin, + passive suffix -ema.
A tissue in vascular plants that conducts food from the leaves and other photosynthetic tissues to other plant parts. Phloem consists of several different kinds of cells: sieve elements, parenchyma cells, sclereids, and fibers. In mature woody plants it forms a sheathlike layer of tissue in the stem, just inside the bark. See more at cambium, photosynthesis. Compare xylem.