Fig. 5.1-10. Transverse section through vascular bundle of Cordyline (no common name). The conducting cells of xylem have thick, red-stained secondary walls because they are a type of sclerenchyma, so it can be difficult to distinguish between fibers and conducting cells in transverse sections. In this vascular bundle, however, the xylem cells have lignified their walls – and so have become red-stained – whereas the fiber walls are not lignified and not red-stained. Consequently, it is easy to tell one type of cell from the other. Notice that the phloem is completely surrounded by fibers.