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SOME OBSERVATIONS ON THE CHICKWEED.
resistance to adverse influences. The one (closely allied) is
Stellaria graminea, and the other is the Scarlet Pimpernel (Anagallis
arvensis). The latter, although belonging to quite a different
order, has some strong points of resemblance to the Chickweed,
being very often its companion in adversity and prosperity.
Both, I have noted, will survive when the clod of earth in which
the roots are affixed has been frozen quite through, and both too
will survive after that clod has been rendered air dry for days,
and in the case of the Chickweed for even weeks. Moreover,
both plants are very impatient of water in the bloom and will
fold up all the envelopes of the flower against rain or damp
weather. Under stimulated growth their behaviour up to a
certain stage is identical, the principal feature being a consider-
able lengthening of the internode.
Stellaria graminea, being an allied species to S. media, may be
supposed to possess all the above points of similarity. I have
chiefly, however, noticed its behaviour under stimulated growth.
The lengthening of the internode is then very much
exaggerated.
So far then these plants respond to the influences of their
environment in a similar manner, but we have now to notice
what sometimes takes place in the case of S. media. It is that
one or more branches of the plant take an upward tendency, and
hang on to the branches of an overshadowing plant, from whence
they still proceed in their upward growth until the top is
reached, where they then often spread out in the normal manner.
In true climbing plants as soon as the ascending stem comes
into contact with a support a process is put out whereby its hold
on this support is strengthened, or otherwise the stem twines
round its support. Nothing resembling either is to be found
in the Chickweed. It exerts pressure on its support, which I
submit is an interesting point in its development, and this,
coupled with the rigidity of the stem, enables it to scramble to
the top sometimes in a very circuitous direction. Were the
plant endowed with consciousness, we should say that it has not
yet learned to climb, although it is very successful in its early
essays.
In describing this tendency to climb I have had to use the
word "sometimes" in two or three cases, and herein appears to
me to lie the interest of the matter. In the other two plants I