_ 85 - TRANSPIRATION. 



19. Demonstration of the transpiration current. 



WATER-ECONOMY. 



20. Examples of xerophytes, showing the following modifications : 

 (a) Reduction of transpiring areas ; 

 (6) Hairy surface ; 



(c) Waxy surface ; 



(d) Water-storage tissues. 



21. Stomata of xerophytes. 



(a) Section of xerophytic leaf showing thick cuticle and sunk-in stomata, to 



be compared with : 



(6) Section through normal stomata, and 

 (c) Section through stomata of a hydrophyte. 



