Cunap, IV. VITACER. 145 
movement, but turn, as was long ago observed by 
Andrew Knight,* from the light to the dark. I have 
seen several tendrils move in less than 24 hours, through 
an angle of 180° to the dark side of a case in which 
a plant was placed, but the movement is sometimes 
much slower. The several lateral branches often move 
independently of one another, and sometimes irregu- 
larly, without any apparent cause. These tendrils are 
less sensitive to a touch than any others observed by 
me. By gentle but repeated rubbing with a twig, the 
lateral branches, but not the main stem, became in the 
course of three or four hours slightly curved; but 
they seemed to have hardly any power of again 
straightening themselves. The tendrils ofa plant which 
had crawled over a large box-tree clasped several of the 
branches; but I have repeatedly seen that they will 
withdraw themselves after seizing a stick. When they 
meet with a flat surface of wood or a wall (and this 
is evidently what they are adapted for), they turn 
all their branches towards it, and, spreading them 
widely apart; bring their hooked tips laterally into 
contact with it. In effecting this, the several branches, 
after touching the surface, often rise up, place them- 
selves in a new position, and again come down into 
contact with it. 
In the course of about two days after a tendril has 
arranged its branches so as to press on any surface, the 
eurved tips swell, become bright red, and form on 
* Trans. Phil, Soc. 1812, p. 314. 
