4 The Philippine Journal of Science 1917 
TABLE 1.—Velocities of assimilation of carbon diowide at different temper- 
atures (van Amstel, Table VI) and the oe temperature 
coefficients calculated for 10° C. 
Temperature coef- 
Velocity of assimilation at— ficient Quo. 
24° C. | 86.5°C. | 40°C. |24°-36.5°} 36. 5°-40° 
Minutes, | Milligrams oxygen per minute, 
3 200 278 293 1.30 116 
9 200 282 306 1.31 1, 26 
15 200 265 |. 303 1.25 1.46 
21 200 274 235 1,28 11 
27 200 264 246 oe foe 
Aversion Sh 1.23 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 af experiments D and E Ks Blackman and Smith on 
Elodea. | 
Carbon di-| Carbon di- 
Initial Final | oxide assi-| oxide assi- 
Experiment. temper- | temper- |milation at'milation at 
ature, | ature. |initial tem-| final tem- 
perature. | perature. 
bei °C. Grams. Grams. 
RENE Sa ES a eS 7 21 0.0115 0. 0252 
We ee ee a eae e ane 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: ‘and its relation to the concentration of carbon dioxide and 
other factors, Proc. Roy. Soe. London B 83 ak ae ae 389, 
