130 



THE VEGETATIVE ORGANS 



induces increased formation of rhizomes and tubers, but 

 if left exposed to light, the tubers are small, green, and soon 

 develop leafy shoots. A potato plant, therefore, has three 



e. 



Fig. 83. Plant grown from a Slice of Potato.: e, 'eyes' ; 

 e.s, shoot growing from an ' eye ' of the large tuber ; p, slice of 

 potato ; rh, rhizome ; t, tubers. 



kinds of stems : (1) aerial stems, bearing green foliage- 

 leaves and flowers ; (2) rhizomes, bearing small scale- 

 leaves ; and (3) from the rhizomes spring greatly swollen 

 and irregular stems, on which are reduced buds, the 



