314 ANATOMY OF LEAVES. 



ing the secretions found in the bark, wood, and roots 

 of plants, the leaf itself is a secerning organ, and con- 

 tains in its cells and follicles many secretions useful, 

 undoubtedly to the plant itself; but, independent of 

 that, of the first importance in medicine and the arts ; 

 and in supplying food for the support of animal life. 



