431 



especially those of the upper; the radial walls are markedly un- 

 dulating, and almost equally so upon both sides (Fig. 68, C, D). 

 Upon the upper surface there are only a few stomata, upon 

 the lower about 350 persq. mm.: they are fairly evenly distri- 



ct D 



Fig. 58. Coptis trifolia. 



A, Epidermis of the peduncle, showing a stoma (Godthaab; ^""/i). B, Transverse section 

 of a one-year-old leaf (Godthaab; ^^U). C, Epidermis of the upper surface of the leaf 

 (Sukkertoppen; '^"^k). D, Epidermis of the lower surface of the leaf (Sukkertoppen; 

 ""11). £, Section of spongy parenchyma, parallel to the surface, from a one-year-old leaf 

 (Sukkertoppen; äoo/i). p, Sphæro-crystal from the cells of the lower surface (^™'/j). 



buted, but are absent above the large veins. The direction of 

 the stomata is almost similar to that of the principal vein of 

 the leaf-lobe. The epidermis contains chlorophyll. In the 

 young leaves the bundles are not accompanied by any especi- 

 ally well-marked stereom, but in Ihe one-year-old leaves but- 



28' 



