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with the widest part in the center of the leaf and then gradually tapering 
fo either end. This accounts, then, for the variation of the number of 
ducts. The ducts are all peripheral and are surrounded by a single layer 
of strengthening cells and lined by a layer of secretory cells. 
The fibro-vascular region lies in the center of the leaf and is surrounded 
PICKA ENGELMANNI, 
D Duets. E Epidermis. 
S Strength. cells. M Mesophyll. 
F Fibro-vas. bundle. B Bundle sheath- 
A Strength cell within sheath. 
