tTbe Stors of tbe 1Root 15 



In a few years some of these put on a heavy bark, 

 like that of the trunk, and throw out tufts of leaves 

 or twigs. This proves them to l)e branches sent forth 

 underground, at the base of the stem. 



A potato is a thick underground stem. The true 

 roots of the potato-vine are the string-like fibres which 

 grow from the lower portion of the erect stem. What 

 we call the potato is a stem thickened for a food 

 reservoir. The eyes on this potato are buds: by 

 each one is a thin oval or triangular slip of scale — a 

 modified, abnormal leaf. The potato-eyes being 

 planted, with a portion of potato for food, begin to 

 grow and send out stems and leaves. 



What is a lily bulb — a root ? Cut it in two, behold, 

 it is a stem with two buds for next year at its base. 

 These thick white scales are closely packed bleached 

 leaves or leaf-bases, which never develop further, but 

 which are detailed to furnish food to be absorbed by 

 the growing stem. A case nearly similar is afforded 

 by the onion. 



Take a sweet potato ; that has not the eyes nor 

 the scales that an Irish potato shows, to prove its 

 status as a stem. What is it? A sweet jiotato is a 

 thickened portion of the true root. Most of the roots 

 of a sweet potato vine are fibrous, but in places they 

 swell out, forming solid masses, which are store- 

 houses of sugar and starch for plant-food. The tend- 



