12 
Transactions of the Royal Society of South Africa. 
It will also be noticed in the above table that in concurrent experiments 
the results for the transpiration per unit leaf area are reasonably concordant 
in the case of Leucadendron, e. g. Nos. 12 and 13, 16 and 17, 27 and 28. 
With the Pine twigs fewer measurements were made, and Experiments 14 
and 15 show a considerable divergence in respect of transpiration per unit 
leaf area. 
Two sets of experiments were performed to ascertain whether the high 
rate of transpiration continued in the Pine as the twigs were allowed to dry. 
Twigs of both Pine and Silver Tree were kept overnight in water and the 
following morning the cut ends were blocked with paraffin wax. The loss 
of weight was then followed in the one set for five hours and in the other 
for two days. Both sets showed that the rate of loss of the Pine twig was 
greater than that of the Leucadendron during the first two hours, but after 
this it became less. 
Experiments Nos. 20 and 26 : Date, January 20, 1920. 
No. 20 : Leucadendron. 
No. 26 . Pine 
Time. 
Weight of twig. 
Loss of weight. 
Time. 
Weight of twig. 
Loss of weight. 
9.53 a.m. 
37-82 grm. 
9.57 a.m. 
66'54 grm. 
10.56 „ 
3635 „ 
1*47 grm. 
10.59 „ 
62 90 „ 
3 64 grm. 
11.55 „ 
3510 „ 
1-25 „ 
11.58 „ 
5952 „ 
338 „ 
12.17 p.m. 
3493 „ 
017 „ 
12.22 p.m. 
5939 „ 
013 „ 
1.16 „ 
3419 „ 
0-74 „ 
1.19 „ 
5910 „ 
0-29 „ 
2.13 „ 
3359 „ 
0-60 „ 
2.16 „ 
58-86 „ 
024 „ 
3.16 „ 
32-86 „ 
073 
3.20 „ 
5859 „ 
0-27 „ 
Experiment No. 33 ; Date, January 29, 30, 31, 1920. 
No. 33 : Leucadendron. 
Date. 
Time. 
Weight of twig. 
Loss of weight. 
January 29, 1920 
11.6 a.m. 
2746 grm. 
2.4 p.m. 
26-69 „ 
0-77 grm. 
30 „ 
9.20 a.m. 
2315 „ 
3 54 „ 
31 „ 
9.50 „ 
17-80 „ 
5 35 „ 
No. 33 : Pine. 
January 29, 1920. 
11.13 a.m. 
36-05 grm. 
2 8 p.m. 
3324 „ 
2-81 grm. 
30 „ 
9,24 a.m. 
31-57 „ 
167 „ 
31 „ 
9.54 „ 
3017 „ 
1-40 „ 
