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Vegetative parts of plants of Gnetales. (A) Ephedra fragilis, tips of growing photosynthetic shoots. (B) Ephedra sp., detail of stem base with scale leaves removed to reveal meristematic ‘diaphragm’ region (arrow). (C, D) Welwitschia mirabilis, leaf bases. (E–G) Gnetum gnemon leaves. (E) Abaxial views of two mature leaves. (F) Adaxial views of two mature leaves with scale. (G, inset) Youngest leaves examined, shown at same scale as in (F).
