Chlamydomonas and other vegetable cells . 
183 
the time of their death, the counts gave a measure of the number of deaths 
which had taken place after the various intervals of time, and consequently 
of the number surviving after these intervals. That this is the case seems 
most probable from the results obtained. If n x — number of cells surviving 
after an interval of time t 1} and n 2 the number surviving after t 2 , then the 
equation 
1 1 
' 2 — ° g » 2 
— a constant 
is found to be approximately obeyed, within the limits of experimental 
110 
100 
90 
Z 60 
•o 
70 
0 ) 
c 
3 60 
< 
< 50 
Z 
O 40 
50 
i 
20 
10 
10 20 50 
TIME IN MINS. 
Fig. t. Curve showing relation between number surviving and time (actual). 
error, as seen in the fourth column of Table II. Owing to the difficulty 
of obtaining suitable material, I was unable to repeat the two experiments, 
the results of which are shown, or to obtain larger and more satisfactory 
numbers. 
