BEHAVIOUR OF CLIMBING PLANTS 151 
above their smaller neighbours. Some other plants 
which have comparatively weak stems have found 
means of getting up where there is light. Such plants 
cimb. Their stems cannot hold the plants upright. 
They climb on other plants, or on rocks, y 
rN YS 
fences, houses, etc. 
Climbing by coiled 
stems. A common 
way for some plants 
to climb is to coil or 
twine their stems 
round other plants. 
The convolvulus, 
the black bryony, 
the black bind- 
weed, and the 
honeysuckle are | 

examples. W hile F1G. 186, Coiling stem of dodder. 
these plants are \ 
srowing, watch the stems and see how they coil. | 
The young stems are more or less erect; but 
the-end of the stem is often bent to one side. You 
may watch the plant in the field, or several shoots 
may be cut and placed in a vessel of water. Notice 
now which way the bent ends point. In an hour or 
so look again. Some of them are pointing in a 
different direction. If you look at intervals through 

