The Phili'p'pine Journal of Science 
1917 
Table 1. — Velocities of assimilation of carbon dioxide at different temper- 
atures {van Amstel, Table VI) and the corresponding temperature 
coefficients calculated for 10° C. 
Time of 
heating:. 
Velocity of assimilation at — 
Temperature coef- 
ficient Qio. 
24° C. 
36. 5° C. 
40° C. 
24°-36. 5° 
36. 5°- 40° 
Minutes. 
Milligrayns oxygen per minute. 
3 
200 
278 
293 
1.30 
1.16 
9 
200 
282 
306 
1.31 
1.26 
16 
200 
265 
303 
1.25 
1.46 
21 
200 
274 
285 
1. 28 
1.11 
27 
200 
264 
246 
1.25 
1.28 
1.25 
BLACKMAN AND SMITH’S WORK ON ELODEA 
Blackman and Smith have performed two experiments with 
Elodea, which are interesting in this connection. These experi- 
ments are summarized in our Table 2. 
Table 2. — Summary of experiments D and E of Blackman and Smith ort 
Elodea. 
Experiment. 
Initial 
temper- 
ature. 
Final 
temper- 
ature. 
Carbon di- 
oxide assi- 
milation at 
initial tem- 
perature. 
Carbon di- 
oxide assi- 
milation at 
final tem- 
perature. 
D 
°c. 
7 
°c. 
21 
Grams. 
0. 0115 
Grams. 
0. 0252 
K — 
13 
21 
0.0177 
0. 0226 
In the first case the rate of assimilation was determined at 7° ; 
then the temperature was raised to 21°, and another deter- 
mination was made. The second experiment was similar to the 
first, the temperatures in this case being 13° and 21°. The light 
was the same throughout. Blackman and Smith in discussing 
these experiments say : 
By experiment D we have established 0.0115 as the “specific temperature 
maximum” for the temperature of 7° C. and by E the value of 0.0177 for 
the temperature of 13° C. 
“ Blackman, F. F., and Smith, A. M., Experimental researches on vege- 
table assimilation and respiration. IX. — On assimilation in submerged 
water-plants hnd its relation to the concentration of carbon dioxide and 
other factors, Proc. Roy. Soc. London B 83 (1910-11) 389. 
