Fig. 2. Cross‐sections through the seed coat in the chalazal vein region at four different developmental stages between 10 and 30 dpa. A, Overview. B, Epidermis and hypodermis. Between 10–15 dpa the epidermis cells elongate and the hypodermis cells become hourglass shaped. Substantial cell wall formation takes place in both cell layers from approx. 20 dpa onwards. C, Chlorenchyma. Starch disappears after 20 dpa. D, Ground parenchyma. E, Branched parenchyma. Before this cell layer is compressed by the expanding cotyledons (from 20 dpa onwards), it is characterized by small, irregular cells with extensive intercellular spaces. e, Epidermis; h, hypodermis; ch, chlorenchyma; gp, ground parenchyma; bp, branched parenchyma; vb, amphicribral vascular bundle. Bars represent 100 µm (A), or 10 µm (B–E).