48 
NATURE NOTES 
showing liow those features characteristic of aquatic plants 
can soon be brought about by the action of the surrounding 
conditions. 
Climbing Stems. — Many plants climb up others by twisting 
spirally about them. This habit has probably arisen by growing 
in very shady places. The subdued light enables the “inter- 
nodes,” or portions of stem between the joints, to grow freely, 
and this, coupled with the universal habit of “ circumnutating ” 
or “ bowing around,” has resulted in their twisting round neigh- 
bouring objects. Thus the lesser convolvulus growing in a corn 
field climbs up the wheat stems ; but if it happens to grow on a 
sunny bank it creeps along the ground, making no effort to climb 
whatever. 
Many tropical climbers have woody stems, and their anatomi- 
cal structure is very peculiar ; but in all cases it will be observed 
that the details are in harmony with the conditions of growth ; 
some, e.g., being like thick ropes with many strands, supplying 
enormous strength. Some species of the genus Strychnos (to 
which the nux vomica belongs) have converted their branches 
into tendrils, just as the pea has altered its leaves for the same 
purpose. In the case of the vine and Virginia creeper, it is the 
flowering branches which are utilised as tendrils for this purpose. 
If the student will search over a vine plant he will soon 
perceive that a flowering branch carries a tendril at its base, and 
it often happens that this tendril has two or three, or more, buds 
upon it. Conversely, now and then a long tendril shoots out 
from the middle of a bunch of flowers. This shows that these 
two are interchangeable in structure and use. And in propor- 
tion as a tendril bears buds so does the peculiar sensitiveness to 
touch, which it has to enable it to clasp an object, become less 
and less till it is a complete flowering branch, when it has none. 
A plant of the old-fashioned Virginia creeper {Ampelopsis hederacca) 
should be compared with the species which grows close to a 
wall {A. tricuspid at a), and it would be seen that both kinds fi.\ 
themselves by tendrils, not, however, by twining but by means 
of adhesive pads ; and that while the former does not make them 
until contact with the wall has taken place, in the other species 
the pads are hereditary in that they are partially formed before 
contact. 
A RED-LETTER DAY. 
OST observers of nature can look back on days, perhaps 
long past, when something of unusual interest has 
come to their notice — the sight of some animal, bird, 
beast, or insect, or some choice flower or plant; and, 
as time goes on, the very day itself becomes a landmark in the 
