THE POTATO 



small white kidney-shaped seeds embedded in the midst 

 of a green and very acrid pulp (Fig. 3). These seeds 

 are sown for the purpose of raising new varieties. 



The main vertical underground stem varies in length 

 with the depth of planting. This stem branches at in- 

 tervals, and each branch enlarges at the end to form a 

 tuber (Fig. 12). Usually from two to four roots start 

 from the vertical underground 

 stem at the base of each tuber- 

 bearing branch, but roots may 

 start where such branches are 

 absent. This charadleristic 

 growth may be seen by grow- 

 ing a potato in a barrel half 

 full of soil and manure, and 

 watering it well; then, as the 

 stem grows, place soil round it, 

 thus increasing the length of 

 the underground portion and 

 the number of tuber-bearing 

 branches. The tubers may be 

 formed above ground, and 

 whenever they are abundant 

 in the axils of the leaves there 

 are few or none below ground. 



The tuber is an underground 

 stem, and the eyes on it are 

 equivalent to the leaf buds on a stem of a young 

 peach or ailanthus. They are arranged more or less 

 spirally in both cases (Fig. 4). From the eye a num- 

 ber of buds may start; hence, in the case of new and 

 expensive varieties, the tubers may be split through the 



FIG, 4 — KIDNEY-SHAPED 

 POTATO {Does Pride) 



Showing the alignment of 

 the eyes, and that the ter- 

 minal buds tend to start 

 first. Note the short, thick, 

 desirable shoots. 



