Fig. 3.2-5. Transverse section of stem of angelica (Angelica, an ornamental herb in the parsley family) The large red-stained cells at the bottom of the micrograph are xylem cells, the larger ones at the top are phloem cells. The band of flat, cuboidal or box-like cells in between xylem and phloem are vascular cambium cells, another type of synthetic parenchyma. Although these appear to be small cells, like those of the shoot apical meristem in Fig. 3.2-4, the fact that so few nuclei are visible indicates something must be not quite as it appears. These are actually extremely long cells that have been cut in transverse section – most cells are probably about 100 to 200mm long and this section is only about 10mm thick, so there is a 10 in 100 to 200 (1 in 10 to 20) chance of cutting through one of these cells in an area where a nucleus happens to be.