Fig. 6.3-5a. Longitudinal section through a shoot tip of horse-chestnut (Aesculus; this genus also contains buckeye). The zonation of the corpus here is very dramatic, very easy to see. The apical meristem is flanked by two rather large leaf primordia, and on the right side, the procambium (which will produce the vascular tissue) is prominent, running right up to the base of the leaf primordium. Cells to the outer side of the procambium will become part of the cortex, those to the inner side will become pith. A higher magnification is shown in Fig. 6.3-5b.