CHAPTER VI 
LEAVES 
Leaves collectively constitute the greatest manufacturing 
plant in the world. Most of the food, clothing, and medicine 
used by man is formed as a result of the work of the leaf. The 
cell contents, structure, and arrangement of the different cells 
of the leaf differ in a marked degree from the cell contents, 
structure, and arrangement of the cells in the other organs of 
the plant. This accounts for the presence of the large amount 
of chlorophyll in the leaf, the presence of stomata, and the 
peculiar arrangement of the cells. 
It should be ascertained if the stomata are above, even with, 
or below the epidermis; the nature of the epidermal cells, and, 
when present, the nature of the hypodermal cells; the number of 
layers of palisade parenchyma and whether it is present on 
both surfaces of the leaf, and the nature of the outgrowths from 
the epidermal cells. 
KLIP BUCHU 
The cross-section of klip buchu (Plate 108) has the following 
structure: 
Epidermis. The epidermal cells of klip buchu are modified 
to form papillz, the walls are yellowish white, and the papillate 
portion of the cell is nearly solid. 
Hypodermis. The hypodermal cells are never intact because 
the mucilage contained in the cells swells when placed in water 
and breaks the thin side walls. 
Upper Palisade Parenchyma. The palisade parenchyma is 
two layers in thickness. The cells of the outer layer are greatly 
elongated and are packed with chlorophyll. The inner layer 
of palisade cells is more irregular, and the cells are much shorter 
than the cells of the outer palisade layer. 
Spongy Parenchyma. The spongy parenchyma cells are 
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