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side. One tendril was pointing away from the light to begin 
with, and this did not move ; but the opposite tendril, which 
was pointing towards the light, bent right over, and became 
parallel to the first tendril. The pot was then turned round, so 
that both pointed towards the light, and they both moved over 
to the other side, and pointed away from the light. In another 
case, in which a plant, with six tendrils, was placed in a box, 
open at one side, all six tendrils pointed like so many weather- 
cocks in the wind — all truly towards the darkest corner of the 
box. These tendrils also showed a curious power of choice. 
When it was found that they preferred darkness to light, it 
was tried whether they would seize a blackened glass-tube, 
or a blackened zinc plate. The tendrils curled round both 
these objects, but soon recoiled, and unwound with, what 
my father says, he can only describe as disgust. A post with 
very rugged bark was then put near them ; twice they touched 
it for an hour or two, and twice they withdrew ; but at last one of 
the hooked tendrils caught hold of a little projecting point of 
bark ; and now it had found what it wanted. The other branches 
of the tendril quickly followed it, spreading out, adapting 
themselves to all the inequalities of the surface, and creeping 
into all the little crevices and holes in the bark. Finally a 
remarkable change took place in the tendrils : the tips which 
had crept into the cracks, swelled up into little knobs, and 
ultimately secreted a sticky cement, by which they were firmly 
glued into their places. This plan of forming adhesive discs on 
its tendrils is one which we shall find used by the Yirginian 
Creeper, as its only method of support, and it forms the fifth 
means of climbing to be met with among the Bignonias. 
We see now the meaning of the power possessed by the 
tendrils of moving towards the dark, for in this way they 
are enabled to find out and reach the trunks of trees to which 
they then become attached. It seems, moreover, that the 
tendrils are especially adapted to the moss or lichen- covered 
trees, for the tendrils are much excited by wool, flax, or moss, 
the fibres of which they can seize in little bundles. The 
swelling process is so delicate, that when two or three fine 
fibres rest on the end of a tendril, the swelling occurs in crests, 
thinner than a hair, which insert themselves between, and 
finally envelope the fibres. This goes on so that the ball at the 
end of a tendril may have as many as fifty or sixty fibres im- 
bedded in it, crossing each other in different directions. 
The tendrils of the Yirginian Creeper may here be worth 
noticing. This plant can climb up a flat wall, and is not 
adapted to seize sticks or twigs ; its tendrils do occasionally curl 
round a stick, but they often let go again. They, like the 
Bignonia tendrils, are sensitive to the light, and grow away 
