Chap. III. BIGNONIACE^J. 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 a square 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. Ulti- 

 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 when 

 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, 



