GROWTH. 
8 MISS A. BATESON AND MR. F. DARWIN ON THE EFFECT OF 
These maxima are certainly high when we compare them with 
the maxima recorded for normal growth. For the Maize, Pfeffer 
Fig. 1. 
TIME P.M. Fig. 9. 
8.10! 12' 18' 20! 23' 24' 9T! 31! 38! 
450 | 
440 
430 
420 Bl 340 
410 E 330 
400 320 
390 310 
380 300 
370 290 
360 5 280 
350 M 270 
340 260 
330 250 
220 240 
310 230 
300 220 
290 . 210 
280 Ei 200 
210 E 190 
260 © 180 
250 ra 170 
240 © 160 
230 150 
220 140 
210 130 
200 120 
190 110 
180 100 
170 90 
160 80 
150 70 
140 60 
130 50 
120 40 
110 
100 30 dt 7 _ 
M 15° 20° 25° 309 359 409 459 50 55° 60° 
iM TEMPERATURE (° C.). 
eo Bi 
50 
"PT 259 309 359 409 459 50° 559 60° Diagrams showing effects of Rise of 
TEMPERATURE (° C.). Temperature. 
gives 46°2 C. as the highest temperature at which growth occurs ; 
but 56°-57° C. is not a higher temperature than plants are known 
to be capable of surviving*. l 
Pfeffert has pointed out that where the maximum is a very 
high temperature, it often happens that the maximum growth 
* Wiesner, Sitzungsb. der Wiener Akad. 1871, Bd. lxiv., got seeds of Pinus 
Laricio which had been exposed for 15 minutes to temperatures of 55°, 60°, 
and 70° C., to germinate ; and seeds of Abies excelsa exposed to a temperature 
of 70° C. for the same time germinated. 
t ‘ Pflanzenphysiologie,' ii. p. 123. 
