516 THE ROOT-SYSTEM ОЕ IMPATIENS ROYLEI. 
PLATE 38. 
Fig. 9. Adventitious roots developing from a cotyledonous node. 
10. Transverse section near the tip of a pentarch tap-root, showing tyloses. 
11. Transverse section of a primary lateral root showing cork formation in hypodermal 
layers of the cortex. 
12. Transverse section of an adventitious root showing tannin cells and a raphid sac. 
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