Leaf epidermis structure in <i>Castanopsis</i>.

<p>(A) Geographical distribution of leaf epidermis structure. Circle sizes are proportional to sample sizes. (B) Transverse sections of leaves; (i) a leaf taken from a tree growing in Maizuru (population no. 16) has a double epidermal cell layer, (ii) a leaf with a single epidermal cell layer from Ise (No. 48), (iii) intermediate epidermal morphology in a leaf from Hagi (No. 43). Scale bar = 20 µm.