230 Knight. —The Interrelations of Stomatal Aperture , 
In the other experiment given, however, the positions were reversed and 
the relative transpiration maximum fell some hours later than that 
of evaporation. 
A review of the series shows that of twenty-six experiments ten were 
similar to No. 1 above in showing the ‘ early maximum ’ of relative tran- 
spiration, whilst of the remainder, six showed the transpiration maximum 
definitely later than that of evaporation, four showed the two maxima 
occurring at about the same time, and in six both graphs were falling 
throughout the experiment . 1 * * 
Table II. 
Plant. _ Sto?nata. 
Half-hour 
Atmometer 
Transpira- 
Absorption 
Time. 
Sto?natal 
periods 
loss in 
tion in 
in mg. 
aperture. 
ending 
mg (A). 
mg. (T). 
10.15 a.m. 
2 
10.30 
>7 
2 
10.45 
77 
2 
11.20 a.m. 
410 
1270 
1280 
3-io 
11. 15 
77 
79 
11.30 
77 
209 
11.37 
77 
26 6 
11.50 „ 
440 
1800 
1830 
4.09 
11.45 
77 
283 
11-53 
77 
265 
12.0 noon 
224 
2160 
12.5 
p.m. 
203 
12.20 p.m. 
470 
2110 
4.49 
12.10 
77 
168 
12.15 
77 
156 
12.25 
77 
164 
12.30 
77 
176 
12.50 „ 
500 
2270 
2400 
4*54 
12.35 
77 
173 
12.45 
77 
156 
12.55 
77 
i5r 
1.0 
77 
149 
1.15 
77 
169 
1.20 „ 
470 
2270 
2260 
4-83 
1.25 
77 
181 
1-35 
77 
203 
1.45 
77 
214 
i-5° » 
450 
2450 
2500 
5*44 
1.55 
77 
236 
2.5 
77 
208 
* 
5'5<5 
2.15 
77 
193 
2.20 „ 
450 
2500 
2490 
2.25 
77 
171 
2-35 
77 
153 
5-48 
2-45 
77 
129 
2-5° » 
440 
2410 
2520 
2-55 
77 
117 
5* 6 4 
3-15 
77 
67 
3.20 „ 
330 
00 
Os 
O 
1920 
3-30 
77 
56 
3.45 
77 
53 
380 
I560 
1690 
4‘i r 
4.15 
77 
40 
4.20 „ 
34° 
1120 
1170 
3.29 
4-45 
77 
38 
4-50 » 
3i5 
8lO 
900 
2-57 
Total 22430 23120 
Increase in water-content of plant, 690 mg. 
1 It may be noted here that Fig. i above shows the double transpiration maximum observed by 
some writers, but in the present work this has not appeared with sufficient frequency to warrant any 
conclusion as to its nature. 
