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"The Power of Movement in Plants"

* The strength of such inheritance differs
* Pfeffer denies such inheritance; he attributes ('Die Period. Bewegungen,'
pp. 30-56) the periodicity when prolonged for a day or two in darkness, to
"Nachwirkung," or the after-effects of light and darkness. But we are
unable to follow his train of reasoning. There does not seem to be any more
reason for
[[page 408]]
attributing such movements to this cause than, for instance, the inherited
habit of winter and summer wheat to grow best at different seasons; for
this habit is lost after a few years, like the movements of leaves in
darkness after a few days. No doubt some effect must be produced on the
seeds by the long-continued cultivation of the parent-plants under
different climates, but no one probably would call this the "Nachwirkung"
of the climates.
[page 408]
much in different species, and seems never to be rigid; for plants have
been introduced from all parts of the world into our gardens and
greenhouses; and if their movements had been at all strictly fixed in
relation to the alternations of day and night, they would have slept in
this country at very different hours, which is not the case.


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