94 



THE VEGETATIVE ORGANS 



experiment repeated or varied in several ways ; e. g. by 

 coating some of the leaves with vaseline (i) on their 



FlG. 56. POTOMETER, TO MEASURE THE RATE OF 



Transpiration in a Shoot (Farmer). 



upper and (2) on their under surface ; (3) by removing 

 some of the leaves ; (4) by exposing the apparatus to 

 sunlight or (5) to diffused light ; or (6) to dry air or (7) 

 to moist air. 



