ROOTS 



13 



gloxinias, and bryophyllum. In the black-cap raspberry 

 and in dewberries, a shoot (stem) may bend over by its own 

 weight, and where it strikes the ground, develop adventi- 

 tious roots, and thus secure a foothold. When once the 

 tip has rooted well, the stem may be cut loose from the 



GROUND 



l-l NE 



T" 





V 



^■^ 



Fig. 4. — Tap-root system of young sugar beet. (Moxjon.) 



parent stem and such rooted tips used as "sets." Straw- 

 berries produce slender stems, called runners. Adventitious 

 roots may be produced at the nodes. 

 A very different sort of root system develops in such plants 



