10 
The Philippine Journal of Science 
1917 
The figure is similar to that given by Matthaei (p. 65) and 
shows that as the temperature rises from — 6° to +3° there is 
a rapid increase in the rate of assimilation. Beyond this point 
the rate is increased very little if at all by higher temperatures. 
In regard to this part of the curve Matthaei (p. 6, par. 4) says: 
Individual differences in the readings of any one series are hardly 
greater than the experimental error obtained in the actual experiments. 
The part of the curve below 3° shows very much higher co- 
efficients than would be called for according to the van’t Hoff 
principle. At these temperatures many plant processes are just 
coming into activity. Under such conditions it would not be 
surprising to find that a general ratio would not hold for any 
particular function. The present discussion will be confined to 
temperatures between 3° and 33° C., where it is believed that the 
results of Matthaei show little or no increase in the rate of 
assimilation with rises in temperature. 
The next series of experiments mentioned by Matthaei deal 
with light intensities of one, two, four, and six units with va- 
rious temperatures. The details are given in Table V of her 
publication, and are summarized in Table VI, Her summary is 
copied in our Table 6. 
Table 6. — “Summary of the experiments in Table V setting forth the 
ratios of the assimilation with the different intensities of light.” 
(Matthaei Table VI.) 
Experiment No. 
Date. 
Tem- 
pera- 
ture. 
Real aas 
1. 
milation 5 
Light in 
2. 
0 sa. cms. 
tensity. 
4. 
1 
n 1 hour, j 
6. 
1902. 
°C. 
Grams. 
Grams. 
Grams. 
Grams. 
XXVIII 
0.4 
0. 00175 
0.0020 
XXIX 
Apr. 12-13 
8.8 
0. 00225 
0. 00385 
XXX 
Apr.13-14 
9.2 
0. 00205 
0. 00366 
XXXI 
11.4 
0.0022 
0. 00466 
0.00606 
XXXII 
11.4 
0. 0022 
0. 00376 
XXXIII 
Apr.24-26 
11.4 
0. 00465 
XXXIV 
Apr. 29 
26.2 
0. 00215 
0.00616 
•0.0063 
XXXV - 
25.2 
0. 00385 
XXXVI . 
Apr. 19-20 
24,8 
0. 00185 
0. 00485 
* This figure does not appear in Matthaei's Table V. 
The column for unit light intensity shows, as did the previous 
experiments, that with this light there was no change in the rate 
of assimilation with the temperatures that were above 3° C. 
