The result was, that the
cotyledons of five out of the nine seeds thus placed were raised above the
ground still enclosed within their seed-coats. Four seeds were buried with
the end from which the radicle protrudes pointing vertically downwards, and
owing to the peg being always developed in the same position, its apex
alone came into contact with, and rubbed against the tip on one side; the
result was, that the cotyledons of all four emerged still within their
seed-coats. These cases show us how the peg acts in co-ordination with the
position which the flat, thin, broad seeds would almost always occupy when
naturally sown. When the tip of the lower half of the seed-coats was cut
off, Flahault found (as we did likewise) that the peg could not act, since
it had nothing to press on, and the cotyledons were raised above the ground
with their seed-coats not cast off. Lastly, nature shows us the use of the
peg; for in the one Cucurbitaceous genus known to us, in which the
cotyledons are hypogean and do not cast their seed-coats, namely,
Megarrhiza, there is no vestige of a peg.
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