JACQUES LOEB 



301 



In the next experiment one set of six leaves remained intact (Set 

 II) while more than half of the basal part of the set of sister leaves 

 (Set I) was cut off (Fig. 2). The tips of the leaves dipped into 

 water. Again the ratio of the mass of shoots and roots regenerated 

 was, within the Umits of the accuracy of the experiments, the same 

 as the ratio of the masses of the two sets of leaves. It was 0.37 for 

 the leaves and exactly the same number for the roots, while it was 

 slightly larger, 0.45, for the shoots (Table III). 



In the next set, the leaves were suspended sidewise, their lower 

 edges dipping in water (Fig. 3). In both sets of leaves the upper 

 edge was cut off; in one set the lower edge with the exception of one 



Fig. 3. Leaves suspended sidewise. The upper edge is cut oflf in both leaves. 

 In leaf to left all notches except one removed, in leaf to right all notches on the 

 lower side preserved. Duration of experiment 34 days. After nature. 



or two notches was cut off (Set I), while in the other set (Set II) all 

 the notches of the lower edge were left intact. This was done to 

 make the number of shoots produced by both sets unequal and to 

 show that the general law enunciated is independent of the number 

 of shoots produced. Thus, as Table IV shows, the leaves of Set I 

 produced six and the leaves of Set II produced sixteen shoots, yet 

 the mass of the two sets of shoots was almost the same, though it is 

 not impossible that when more shoots develop in one leaf the available 

 material furnished by the leaf can be utilized more fully than when 

 all the material goes into one shoot. 



