SUXrifUBS AND LAYERS 



367 



Do these stalks increase in length or diameter after the tuber be- 

 gins to form? From what part of the plant do these stalks spring? 

 Is there ever a stem on both ends of a potato? From what point 

 do the roots of a potato plant first spring, — from the old "seed" 

 tuber, or from other parts? If an entire tuber is planted, do all 

 the eyes grow? 



LXXI. RUNNERS AND LAYERS 



459. A stalk or culm of a sedge or carex has 

 fallen to the ground in Fig. 386, and from four 

 of the nodes branches have arisen and from two 

 of them roots have started. These new branches 



Pio. 386. 

 Layer of a sedge. 



