CLIMBING AND WATER PLANTS 109 
upwards, along or through the supporting 
vegetation, only produces minute leaves, and 
at very distant intervals. It is not until the 
roof of the forest is reached that the large 
crop of big green leaves is unfolded, and their 
weight is entirely borne by the vegetation 
over which they are growing and spreading. 
Entangled as the climber becomes among the 
branches of the sustaining trees, it is evident 
that when the latter are swayed by the wind, 
the danger of snapping which confronts its 
thin stems is a very real one. Furthermore, 
while the plant is a young one, the risk of 
being parted from the root isnot small. These 
difficulties are all obviated in several ways. 
In many of them the first formed wood of 
the young plant consists almost entirely of 
strong mechanical tissue, and this is especially 
true of those climbers which produce no 
functional leaves worth mentioning till they 
reach the roof of the jungle. The presence of 
this axile cord of sclerenchymatous wood is 
most important to all these plants, for they 
need to be very flexible, and at the same 
time to be able to withstand very considerable 
pulls which might otherwise snap them 
asunder. The fact that they are admirably 
constructed in these respects is illustrated by 
the name of “jungle ropes,’ by which so 
many of them are commonly known—a 
popular tribute to their flexibility and their 
very great strength. 
But it is evident that stems constructed 
