156 BOTANICAL GAZETTE [FEBRUARY 
Tables III and IV show a slightly greater variation than tables I 
and II, owing to the inevitable errors in such experiments (errors in 
cutting off and ascertaining the weight of the small shoots, errors 
in evaporation, differences in the condition of the two sister leaves, 
TABLE III 
APRIL 11—MAy 10, 1917 
: i : Mem. of shoots 
: Number of | Weight of shoots| Weight of | 
Sister leaves canes tgs poy 00 ba a omen oe 
I Test eee aay oe 2 °.180 1.655 10g 
AEM Bod ie cis I 0.201 1.590 126 
II (reat Pee vars 2 0.115 1.050 109 
gS ae Be 2 ©0.166 1.505 IIo 
WE Pe ae 3 0.155 1.081 143 
Il. ‘Teal Po eee 2 0.140 1.098 127 
SOME Po ats ieee - 0.123 1.158 106 
Iv. (Keat Bae a veces 3 °.126 1.245 . 101 
V pee Ree ee eed ee 2 ©.110 1.038 106 
ee reer eee t 2 0.089 _ ©.995 go 
VI BME 2s os a ve ess 2 0.183 1.646 IIL 
MAME Bie rer 04% 2 0.153 1.383 111 
Re ee 3 0.231 1.617 143 
WE Meta 3 0.178 1.463 122 
BE fy RS Se ae 4 0.220 1.547 142 
Vill. Test 7 Beare SUMacde: 2 0.146 ¥:177 125 
ND pare eee 3 0.119 1.230 97 
i (Leal eee Pisa s es 3 ©.149 1.410 106 
RPBVOE Bic eas ei eens 1.436 12.022 + 119 
aveeage tare ens re Senet Bee 1.348 11.861 114 
and in the external conditions of moisture and light, and others). . 
The fact that these errors are accidental is proved by the proximity 
of the average shoot production in each set of leaves, which is 119 
and 114 mgm. of shoots per gm. of leaf in table III, and 106 and 
109 mgm. in table IV. 
We may make the following statement, therefore: Two healthy, 
isolated sister leaves of equal mass will produce in equal times and 
under equal conditions approximately equal masses of shoots, although 
