ISOLATED LEAVES OF BRYOPHYLLUM 



13 



Experiment 2. — Nineteen pairs of sister leaves were used, one 

 leaf of each pair (designated as 2 in Fig. 15) was left intact, while 

 each sister leaf was cut into a small apical and a larger basal piece 

 (la and 1&). All dipped with the apical end into water (Fig. 15). 

 The figure shows that the roots and shoots produced by sister 



Fig. 15. — One leaf (2) intact, the sister leaf cut into 2 pieces, a small apical 

 one (la), and a larger basal one {lb). Shoot and root production are in pro- 

 portion to the mass of the pieces. Mar. 26 to Apr. 17, 1923. 



leaves varied approximately in proportion to the mass of the 

 pieces of the leaves. This was confirmed by the measurements 

 in Table 11. The experiment lasted from Mar. 26 to Apr. 

 17, 1923. The 19 whole leaves are termed Set II, the 19 sister 

 leaves each cut into two pieces, la and 16, are termed Set I. 



