LEAVES OF THE SUGAK BEET. 91 



CHAPTER III. 



LEAVES OF THE SUGAR BEET. 



There can be no doubt as to the important role 

 which the leaves play in the beet culttire. As before 

 stated, their exterior signs give evident proof in many 

 cases of the qualities of the root to which they belong. 



The functions which they have to fulfil are most in- 

 teresting. These we consider have for an object the for- 

 mation of the greater quantity of the final sugar in the 

 root, the most important element being carbon, which 

 is partly or entirely absorbed as carbonic acid ; the latter 

 being partly decomposed, a certain quantity of the 

 oxygen is thrown out. The remaining carbonic acid 

 seems to circulate for a time in the tissue. During the 

 growth of the leaves the root increases but compara- 

 tively little in size, and, as soon as complete, the conti'aiy 

 action takes place. Evidently the greater their size the 

 larger the. amount of the elements which they are able 

 to extract from the surrounding air, and their total 

 weight is up to a certain period greater than that of 

 the root. Each leaf has apparently communication 

 with a given portion of the beet, and supplies it with 

 the nourishment it requires. 



The outer borresponds to the inner portion of the 



