under Various Electrical Conditions. 143 
text in each case, and an account of the repetitions of many of the 
experiments will be found in the Appendix. 
In plotting the curves, each figure for carbon dioxide is attributed to 
the point of time terminating the period for which that value was obtained : 
thus in No. 113, Fig. 3, the number o-oioo represents the carbon dioxide 
output for the second half-hour and is plotted at time one hour. 
The ‘normal curve’ of respiration, as represented by No. 113, Fig. 3, 
takes a decided downward trend from the beginning, its slope decreasing 
with time, until, about two hours from the start, the variations are reduced 
well below 10 per cent. This downward trend was observed in every 
Fig. 3. 
control experiment carried out with germinating seeds, and is doubtless to 
be attributed to the fact that moisture is continually evaporating from the 
surface of the seeds, and owing to this loss of water the vital processes are 
retarded, the conditions gradually approaching the normal winter state, 
when respiratory functions are practically at a standstill. 
It has been observed that slight alterations in the experimental con- 
ditions have a corresponding influence upon the shape of the curve, and it is 
perhaps advisable to enumerate these here. 
The position of the first point of course depends primarily upon the 
number of seeds employed and the extent to which they have germinated. 
The initial slope of the curve varies, as shown by a comparison of 
Nos. 53 and 59, and this is probably due to the variation in the rate of 
