Cuap. III. BIGNONIACE. 105 
capreolata; but the whole does not move from the 
light, nor do the hooked tips become enlarged into cel- 
lular discs. After the tendrils have come into contact 
with a moderately thick cylindrical stick or with 
rugged bark, the several branches may be seen slowly 
to lift themselves up, change their positions, and 
again come into contact with the supporting surface. 
The object of these movements is to bring the double 
hooks at the extremities of the branches, which natu- 
rally face in all directions, into contact with the wood. 
I have watched a tendril, half of which had bent itself 
at right angles round the sharp corner of asquare post, 
neatly bring every single hook into contact with both 
rectangular surfaces. The appearance suggested the 
belief, that though the whole tendril is not sensitive to 
light, yet that the tips are so, and that they turn 
and twist themselves towards any dark surface. Ullti- 
mately the branches arrange themselves very neatly 
to all the irregularities of the most rugged bark, so 
that they resemble in their irregular course a river 
with its branches, as engraved on a map. But wher 
a tendril has wound round a rather thick stick, the 
subsequent spiral contraction generally draws it away 
and spoils the neat arrangement. So it is, but not in 
quite so marked a manner, when a tendril has spread 
itself over a large, nearly flat surface of rugged bark. 
We may therefore conclude that these tendrils are not 
perfectly adapted to seize moderately thick sticks or 
rugged bark. If a thin stick or twig is placed near 
a tendril, the terminal branches wind quite.round it,. 
