4 MISS A. BATESON AND MR. F. DARWIN ON THE EFFECT OF 
the Grand Period of Growth. We do not pretend that this phe- ° 
nomenon has necessarily any connection whatever with the grand 
period of normal growtb, since we are aware that purely mecha- 
nical changes, such as the untwisting of a Stipa-awn in water, 
exhibit a similar series of rates. But the fact is undoubtedly 
worthy of record, and possibly of further investigation. 
Exp.1.— Aug. 14,1886. Sunflower-pith and auxanometer-lever. 
The cylinder was filled with water at 10.10 a.m. 
Times of observation. Rate of Times of observation. Rate of 
A.M. * growth." AM * growth." 
1012  ........ 80 10.16  ......... 142 
89 10.16°2 ......... 149 
10.13  ......... 100 133 
10.132 ......... 111 10.171 ......... 133 
10.13:5 ......... 117 1018  ....... 123 
10.14  ......... 133 10.185 ......... 117 
10.142 ......... 138 10.24  ......... 85 
10.145 ......... 153 74 
10.15  ......... 151 10.28 — ........ 60 
151 
151 
Exp. 2—Aug.3,1886. Jerusalem Artichoke ; lever. 
Times of observation. Rate of | Times of observation. Rate of 
P.M. * growth." | P.M. “ growth.” 
52. ........ Water. | 5.6 esne 270 
107 | 263 
192 | 250 
222 | 250 
256 | 243 
285 ' ! 59 ....... 222 
56 ann... 285 | 222 
277 | 
Whatever may be the significance of the “apparent grand 
period,” it was of importance for our work that its existence 
should be known, since it is obvious that we could not draw any 
conclusions as to the action of reagents till the normal course of 
things was known. 
EFFECT oF WARMTH. 
The results of warming the water in which the pith is placed 
are of considerable interest, as showing that, although the increase 
in length of pith, freed from the surrounding tissues and placed 
1n water, must necessarily be abnormal in character, yet that it 
behaves in a normal manner in response to variations in the 
