252 Darwin and Per is, — On the Production 
Exp. V. May ii, 1891 . Dandelion . 
p. 
Minutes. 
Movement. 
17 
I 
3 
D 
10 
U 
II 
W hH 
1 00 0 
D 
U 
III 
30 
D 
IV 
21 
U 
7 
D 
V 
25 
U 
4 
D 
7 
D 
VI 
15 
U 
5 
D 
5 
D 
VI 
10 
U 
12 
D 
| 20' A 
i 
1- 69' B 
I 
J 
| 32' A 
26' B 
20' A 
Exp. V (in which there are some difficulties of interpreta- 
tion) again shows an irregular rhythm approaching in some 
places to the half-hourly period. 
The movement is more readily followed when expressed 
graphically. Fig. 1 gives the result of Exp. VI. 
