LUTHER BURBANK 



It must supply nourishment to the multitudin- 

 ous cells that make up its root and stem and 

 branches, which, as we have seen, are quite in- 

 capable of extracting nourishment from the crude 

 salts in solution that they are constantly trans- 

 porting. 



But incidentally, in manufacturing food for its 

 own cells, the plant is producing a supply of food 

 that will be available for the sustenance of animal 

 cells also. Thus the entire animal world may be 

 said to be a vast parasitic colony as absolutely 

 dependent upon the vegetable colony for its essen- 

 tial food supplies as any other parasite is 

 dependent upon its host. 



When we consider the matter in thie light, 

 it is pretty obvious that about the most interesting 

 thing in the world, from the standpoint of animal 

 economy— which of course includes human 

 economy — is the wonderful laboratory or factory 

 of the plant where alone is effected the transfor- 

 mation of the crude inorganic elements into such 

 combinations as are available for the sustenance 

 of life. 



When we reflect that the plant laboratories in 

 which this wonderful and vitally essential trans- 

 formation is eif ected are chiefly located in the leaf 

 of the plant, it appears that the thoughtful person 

 must regard this structure — the most "ordinary 



[26] 



