THE LIFE OF THE LEAF 



green jelly embedded in protoplasm, which 

 under a microscope is seen to be full of holes; 

 sometimes these holes are found filled with 

 starch, which may be transformed into grape- 



Cell showing Nucleus and Protoplasm. Greatly Enlarged. After Atkinson. 



sugar, and passed on and down Into the tree, 

 feeding the cells and promoting the growth of 

 the tree body, or going on to produce the fruit 

 of the tree, or forming in combination other 

 products such as cellulose, oils, and gums. 



There are four essential conditions to the suc- 

 cessful productive activity of the leaf. Sunshine 

 must fall upon it, carbonic-acid gas must be in 

 the surrounding air, so that it can be absorbed 

 through the stomata, water must be supplied from 

 the roots in continuous and unfailing flow, and the 

 temperature must not be too low. Under these 

 conditions the leaf sways with the wind, dances 



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