PLATE 1o1 
‘A. Cross-section of buchu stem (Barosma betulina (Berg.], Barth. and 
Wendl.). 1, Outer wall of epidermis; 2, Cell cavity of epidermal cell; 3, Wall 
of cork cell; 4, Cavity of cork cell; 5, Phellogen layer; 6, Divided phellogen 
cell changing into a cortical parenchyma cell; 7, Cortical parenchyma cell. 
B. Cross-section of leptandra rhizome (Leptandra virginica {L.], Nutt.). 
1, Parenchyma cells undergoing change in the composition of their walls; 2, A 
break in the epidermal tissue; 3, Parenchyma cells undergoing division, 
