346 H. W. Turpin 
explained above), is shown in table 9 (appendix, page 362) and in figure 60. 
It will be noticed that increases in temperature were more frequently 
accompanied by rises in carbon dioxide in the bare soil (indicating a 
relationship between bacterial activity and carbon-dioxide production), 
than by rises in the carbon dioxide produced by the crop. Inthe latter 
Per cent : Temp. 
of CO2 a (C.) 
2.4 - Bee 
98 JEL? DCI IIUTE 35° 
5 Carbo Hoxe trotr 7(Mef COP —= —= —=|. 340 
OO CO?D007 HONG 117 LA°E SOl/oee JN 
a* Ie aR 
Hin Ke 
1.8 ! ~ 
1.6 
1.4 i 
1.2 } 
1.6 
a 7 S e 
0.8 iter are 
PSN ys 
~ Ve 
0.6 a7 co! 
0.4 
0.2 4 
8 12 
August 
Fic. 60. RELATION BETWEEN THE CARBON DIOXIDE PRODUCED BY A MILLET CROP, 
THE CARBON DIOXIDE IN A BARE SOIL, AND THE TEMPERATURE OF THE SOIL AT THE 
TIME OF SAMPLING, 1918 
case no such close relationship appeared, but the carbon dioxide mereased 
gradually as the age of the plant advanced until the point of maximum 
carbon-dioxide production, after which there was a decline. This increase 
in carbon dioxide seems to have kept pace with the rate of growth of the 
plants. At the time when the plants ceased to grow actively (some time 
after heading), the carbon-dioxide production also fell off. If the excess 
Bie. 
