THE LIFE OF THE LEAF 



minute passages lying among the green cells of 

 the leaf, and seem to be fairly automatic in 

 their action; when there is too much moisture 

 in the air they become gorged and close, if too 

 little they dry and open so as to get all there is. 



Stomata, Closed and Open 



These stomata are easily seen under a micro- 

 scope, are irregularly placed, and their number 

 is simply enormous. For example, scientists 

 report that in an apple leaf there are about 

 158,670 in each square inch of the lower surface, 

 moreover, they say that apple leaves are under 

 rather than over supplied. When we consider 

 what the leaf does we shall understand the need 

 of these millions of breathing vents for the 



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