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Lazniewski (Flora, 1896) has described the leaf-anatomy of 

 this species very accurately and has given flgures of it. He 

 points out that the leaves are seated so closely together that, 

 for the greater part, they overlap each other, and he then 

 emphazises the fact that only that part of the leaf which is 

 covered by neighbouring leaves bears stomata abundantly, while 



Fig. 29. Saxifraga oppositifolia. 

 The epidermis of the leaf: A and G, of the upper surface; В and D, of the lower surface. 



{A, B, C, D 2«2/i). 



the light-exposed leaf-apex is almost without them, and has a 

 very thick outer epidermal-wall and true palisade-cells (which, 

 on the other hand, are absent from the shaded part). Lazniewski 

 maintains that this distribution of the stomata is also found in 

 rosette-plants and regards it as a protection against excessive 

 transpiration. Ук 



19* 



