t914] HASSELBRING—EFFECT OF SHADING 275 
be placed in the results than would be possible if the plants had 
been selected from an indiscriminate mixture. The result of this 
selection was manifested in the uniform growth of the plants in 
each of the two stations. The data relating to the total transpira- 
tion of the two sets of plants are given in table VI. 
TABLE VI 
WATER TRANSPIRED BY PLANTS DURING 60 DAYS OF GROWTH 
OPEN SHADE 
| Water ——— Water — 
No. Total water ts sah Total water | Per Bram o 
0. of plant transpired der Be No. of plant transpired pe Roos 
produced produced 
_ So) 
ok eee §1,256 cc. 246 OY Cl. 16 ss eg 41,117 CC. 194.47 CC. 
Bets t ces 41,328 245.52 i. 37,39 
3 ee 45,959 239.48 Tao ae 35,494 192.20 
a... 66 939.600 (Tie), 4.3.0 5 ee 191.38 
a 45,625 246.54 PY ara es tl 32,035 176.31 
rates sss 44,402 235.93 pe es de 31,396 180.16 
Average... . 45,539 241.72 Average....| 35,212 186.99 
| eee es 
Table VI shows that the sun plants transpired on the average 
10 liters (about 30 per cent) more water per plant than the shade 
plants, Although the figures show considerable fluctuation in 
transpiration among the individuals of each set, yet if the plants of 
the two sets are compared in the order of magnitude of their tran- 
‘piration, it will be found that the difference between the mem- 
bers of the different series is practically the same as the difference 
between the averages for the whole series. Since the average weight 
of dry matter produced was the same in the two sets of plants, it 
follows that the series having the higher total transpiration also has 
the highest transpiration per gram of dry plant substance. This 
'S substantiated by the figures which show that the shade plants 
transpired 186.99 cc. of water for the production of one gram of 
Plant substance, while the sun plants transpired 241.72 cc. for one 
sm, or about 30 per cent more than the shade plants. The 
quantity of water transpired per unit of dry matter produced is 
remarkably uniform for the plants within each group. A similar 
“ose agreement between the quantities of water transpired per unit 
