164 BOTANICAL GAZETTE [FEBRUARY 
symmetrical. The photograph was taken 36 days after the begin- 
ning of the experiment. It will be seen that the size of the shoot 
varies with the size of the piece, but that some of the smallest pieces 
have failed to form shoots. ‘This fact is to be considered in experi- 
ments in which one leaf is left intact and the sister leaf cut into 
as many pieces as there are notches. In that case it may happen 
that the law of equal production of shoots by equal masses of leaves 
TABLE IX 
SISTER LEAVES: (@) WHOLE LEAF, BUT ALL NOTCHES WITH EXCEPTION OF ONE REMOVED, 
b) CUT INTO 4 PIECES, BUT NO NOTCH REMOVED; APRIL 5—APRIL 25, 1917 
“Sister loaves — of Nabe pag eg wear - — eS ate pg md 
I f(a) Whole leaf... ... I 0.1935 2.403 8 
V ANB) 4 peecest. 6 seuss 6 0.206 2.267 gI 
IL. f(a) bird He es, I 0.110 2.234 49 
1) 6 eee 6 0.105 2.431 43 
I. ieee — sg Fe I 0.136 1.647 Bs 
(i) 4 mech... 5... 5 0.185 2.083 89 
IV. i) We Malo Pea I 0.196 1.8325 107 
Pie ene 7 0.2975 2.387 125 
V. 18) Whole leaf... ... I 0.201 2.035 99 
(h) a Hees. 4 0.246 2.225 110 
VL. io a federal leat oes. I 0.110 1,086 Io 
(O) 4 ite 4 0.154 1.4015 109 
Total number of| Total weight of | Total weight of | Shoots per gm. 
shoots shoots leaves of leaf; mgm. 
nce | (4) Whole leaves. 6 0.9465 ty. 237 84 
Average \(b) Cut leaves... a2 1.193 12.794 93 
may not hold strictly, for two reasons: (1) some of the small pieces 
may not form any shoot at all or form it only too late; (2) a compli- 
cation may vitiate the result in the opposite direction, namely, that 
the shoots formed by small pieces can use the material available for 
shoot formation more readily than the shoots in the whole leaves. 
Table XI gives the results of such an experiment on 3 pairs of sister 
leaves, one leaf remaining intact or cut into two symmetrical halves, 
while the other was cut into as many pieces as there were notches. 
