Fig. 5.2-2. Transverse section of stem of cosmos (Cosmos). This is a mass of fiber cells cut in transverse section. There are no nuclei at all, and most cells appear completely empty. A few fibers have a bit of crumpled debris perhaps the remnants of the protoplasts that did not break down completely when the cells died. Although the fibers died soon after they matured, the surrounding stem tissues have remained alive and healthy.