Problem of Xeromorphy in Marsh Plants. 
823 
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LEAF No. 10 
Text-fig. 4. Three leaves from one erect flowering shoot of S. Ulmaria , var. denudata. The 
months indicate time of unfolding. Below each leaf are shown successively (a) part of its upper 
epidermis, superposed on palisade cells, ( b ) part of lower epidermis, with stomata, and (c) section 
of leaf lamina. Intercellular spaces are black. Shaded cells are at a somewhat different level to the 
others. Leaf outlines x about § ; all other drawings x 350. 
