Fig. 1. General Borszczowia aralocaspica seed structure. (A) Heterocarpous seeds with light, thin coats and dark, thick coats. Bar = 0·2 cm. (B) Cross‐section of cotyledon in seed. All the cell layers of the mature cotyledon are already present. Bar = 20 µm. (C) Immunolocalization of Rubisco in cotyledon in seed (label appears as yellow dots). Some Rubisco is already present in plastids throughout the seed tissues. Bar = 20 µm. Ch, chlorenchyma tissue.