460 
BOTANICAL GAZETTE 
[JUNE 
that is, to the increased radial pressure of the contact Poet. 
against the support, due to the pull of the weight. 
TABLE II 
DURATION OF EXPERIMENT 32 DAYS* 
Free Contact ne ocho aay 
I,—112 grams I,— 775 grams I,—1425 grams 
G:—150 G.— 725 G;—1170 
E,— 8 : 
E:—125 ea Gr E,—1050 
1—450 31040 Fy—1275 
H:—740 H,—1270 H,—1350 
D:—390 D:— 850 D;—1095 
B:— goo B,—1050 
A,— 575 A;—12 
K:—120 Ka. 375 K;— 400 
M:—152 so S75 
Ni—240 N.— 650 N;—1275 
L:—100 ee Eee 
i: Lé— 660 
7s 
Js—155 Jz— 450 i 
U:r—130 U,— 970 U;—1125 
Vi-— 45 V;—1110 
W:—185 W.— 365 
ages PF es 575 
"oa ® 
C.—110 C,— 408 Cs— 905 
C;—145 
P,—100 P:— 760 
cS Ri— 705 
ae, O.— 420 
ie oe Os— 660 
2g sae 
verage ; Average Average 
(20 tendrils), 190 (26 tendrils), 651) (17 tendrils), 1007 
* Capital letters ree vines, subscripts denote tendrils, which were numbered consecutively on 
the vine from below wu 
2. Middle third.—To determine the influence of tension alone 
the following method was devised. In the one set a ligature was 
tied at the distance of a third the length of the whole tendril from 
the tip, and another the same distance from the base (fig. 1). 
To the distal ligature tension was applied by running the cord 
over a pulley, and from the proximal ligature a cord ran to the 
stem, which was made taut, so as to relieve the basal third of the 
