HOW PLANTS CLIMB. 
17 
26. There is great variety in the behavior of different tendrils. Those of the 
Grapevine do not make sweeps, but stretch out away from the light, or in the 
direction from which least light comes, — an instinct which is apt to lead them 
to a support, — and the two forks diverge, as if feeling for something to lay hold 
of. When they reach anything that can be surrounded, one fork commonly grasps 
from one side, the other from the opposite side, somewhat as an object would be 
grasped by a thumb and finger. 
27. The more branching tendrils of the Virginia Creeper equally turn from the 
light, and therefore towards the wall or trunk, which this climber delights to 
occupy and cover. 
When their tips 
reach the wall they 
expand into a disk 
or flat plate, which 
adheres firmly to 
the surface. This 
particularly adapts 
the Virginia Creeper 
to ascending walls 
or other flat sur- 
faces. Thedendrils 
which do not attach 
themselves remain 
slender, and in a 
week or two shrink and wither away. Those that do usually spread their branches 
widely apart, like fingers of an outstretched hand, form their disks and fix them 
fast to the wall ; then they contract more or less into coils, and at length grow 
stronger and more rigid ; so that they last for years, and endure a pretty heavy 
strain without breaking or parting from the wall. It is most interesting to see 
how the strain is divided by these five or six separate attachments, by the coiling 
of each branch to give elasticity, so that the pull shall come upon all at once, and 
to note the strengthening of the whole by the formation of more woody fibre. 
The strain is distributed among the branches, and the whole combination is so 
strong that it is rarely torn away by wind or storm. 
28. In revolving tendrils the most wonderful thing to remark is the way in 
2 
Fig. 7. Virginia Creeper : tendril beginning to form its disks or holdfasts. 8. Older 
branches with full-formed disks. 
