36 TWINING PLANTS. Cuar. I. 
laterally from one to the other pot; but as the 
plants grew older, some of the shoots twined regu- 
larly up thin upright sticks. Though the revolving 
movement was sometimes in one direction and some- 
times in the other, the twining was invariably from 
left to right ;* so that the more potent or persistent 
movement of revolution must have been in opposition 
to the course of the sun. It would appear that this 
Hibbertia is adapted both to ascend by twining, and to 
ramble laterally through the thick Australian scrub. 
I have described the above case in some detail, 
because, as far as I have seen, it is rare to find any 
special adaptations with twining plants, in which 
respect they differ much from the more highly organ- 
ized tendril-bearers. The Solanum dulcamara, as we 
shall presently see, can twine only round stems which 
are both thin and flexible. Most twining plants are 
adapted to ascend supports of moderate though of 
different thicknesses. Our English twiners, as far as 
I have seen, never twine round trees, excepting the 
honeysuckle (Lonicera perielymenum), which I have. 
observed twining up a young beech-tree nearly 4} 
inches in diameter. Mohl (p. 184) found that the 
Phaseolus multiflorus and Ipomea purpurea could not, 
* In another genus, namely 
Davilla, belonging to the same 
family with Hibbertia, Fritz 
Miiller says (ibid. p. 349) that 
“the stem twines indifferently 
from left to right, or from right to 
left ; and I once saw a shoot which 
ascended a tree about five inches 
in diameter, reverse its course in 
the same manner as so frequently 
occurs with Loasa,” 
