JACQUES LOEB 



701 



As a consequence we have an abundant supply of roots in practi- 

 cally every notch of the leaf. In the upper lateral leaves which are 

 suspended sidewise the growth of roots is again more abundant in 



Ha 



Ya 



Fig. 12. The same leaves as in Fig. 11, but 25 days later, showing that the 

 more rapid development of roots on the lower side of Leaves I to V retards or 

 inhibits the development of roots on the upper side of the leaves. In Leaves 

 I a to V 0, where the lower edge is cut off, the development of roots and shoots 

 on the upper side is not restricted. 



the notches on the lower side, while no such influence of gravity is 

 noticeable in the lower central leaves. This difference has been 

 discussed in a previous paper and the influence of gravity on the 



