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multiflorus, to behave as
its progenitors once did, the hypocotyl (h, Fig. 59), in whatever position
the seed may have been buried, would become so much arched that the upper
part would be doubled down parallel to the lower part; and
* An instrument devised by Sachs, consisting essentially of a slowly
revolving horizontal axis, on which the plant under observation is
supported: see 'W?rzburg Arbeiten,' 1879, p. 209.
[page 94]
this is exactly the kind of curvature which actually occurs in these two
plants, though to a much less degree. Therefore we can hardly doubt that
their short hypocotyls have retained by inheritance a tendency to curve
themselves in the same manner as they did at a former period, when this
movement was highly important to them for breaking through the ground,
though now rendered useless by the cotyledons being hypogean. Rudimentary
structures are in most cases highly variable, and we might expect that
rudimentary or obsolete actions would be equally so; and Sachs' curvature
varies extremely in amount, and sometimes altogether fails.


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