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Fig. 11. Part of stem of unequally illuminated plant showing approach to dorsiventral 
condition. 
Fig. 12. Unequally illuminated plant with two prostrate secondary axes showing 
dorsiventrality and anisophylly. 
Fig. 13. Secondary axis of 12, on a larger scale, showing difference in size of dorsal 
and ventral leaves. 
Fig. 14. Transverse section of young root showing endophytic fungus and cortical 
cavity. 
Fig. 15. Transverse section of old root. 
Fig. 16. Transverse section through aerial part of young root of secondary axis. 
Fig. 17. Part of transverse section of young stem. 
Fig. 18. Section of older stem with base of leaf and ligule. 
Fig. 19. a. Part of leaf-margin with stomata. 6. Part of epidermis of leaf-base with 
stomata abutting upon thickened epidermis of stem destitute of stomata. c. Stoma with 
neighbouring epidermal cells elongated in direction of leaf -margin, d. Normally placed 
stoma and stoma with guard cells transverse to long axis of leaf. 
Fig. 20. Vertical section through leaf-base showing aerenchyma, stomata, and 
tracheides at base of ligule. The leaf -trace is cut obliquely. 
Fig. 21. Horizontal section through superficial aerenchyma of leaf -base. 
Fig. 22. Transverse section across leaf -blade. 
Fig. 23. Outline of leaf showing triple vein, position of ligule, and of stomatal area 
of leaf-base. 
Fig. 24. Part of leaf cleared in caustic potash showing the protoxylem and two parallel 
bands of transfusion tracheides continuous with reticulate tracheides at base of ligule. 
Fig. 25. Variations in shape of ligule. The glossopodial cells are not shown. 
Fig. 26. Transverse section through base of ligule showing tracheal sheath. 
