Koelreuter, who repeats this account in his ‘Historie der Versuche,’
a record of the experiments made between the years 1691 and 1752 on
the sexes of plants, ends his narrative with these words: ‘These
are, as far as I know, all the attempts which have been made and
described since the year 1691 to prove the existence of sexes in
plants.’ Koelreuter’s book was written to show that experiment only can
determine the question of sexuality in the vegetable kingdom, and that
no one beside Camerarius, Bradley, Logan, Miller, and Gleditsch had
pursued this method up to 1752.
While these botanists occupied themselves with the question whether
there was a distinction of sexes in the vegetable kingdom, we meet with
two writers at the beginning of the 18th century who regard sexuality
as proved, and who take up the question of the mode in which the
pollen brings about the formation of the embryo. Both were adherents
of the theory of evolution, bad observers, and not familiar with
the literature of the subject. The first is SAMUEL MORLAND. In the
‘Philosophical Transactions’ of 1702 and 1703, p. 1474, he names Grew
as the man who had observed that the pollen answers to the male semen,
but he makes no allusion to Camerarius’ experiments, the only ones
which had as yet been made. He himself suggests that the young seeds
may be compared to unfertilised ova, while the pollen-dust (farina)
contains embryo plants, one of which must find its way into every
ovule (ovum) in order to fertilise it. If so, the style must be a tube
through which the embryos pass into the ova. He supposes the pollen in
Fritillaria imperialis to be washed by wind and rain from the stigma
through the style into the ovary, without reflecting that the movement
must be an upward one in the hanging flower. If I could prove, he says,
that embryos are never found in unfertilised seeds, this would be a
demonstration; but I have never been so fortunate as to settle this
point. He does not mention that Camerarius had shown this ten years
before; he can only give as the main argument for his conjecture,
that in beans the embryo lies near the orifice of the seed-coat (the
micropyle), which shows that he was not aware that the two large
bodies in the seed of the bean (the cotyledons) belong to the embryo,
a fact which his countrymen Grew and Ray had already pointed out. It
appears therefore, that Morland supplied no answer to the question how
fertilisation takes place; his treatise contains nothing more than the
assertion that the embryo is already contained in the pollen-grain, and
that it reaches the seed through a hollow style and is there developed,
an entirely erroneous and not even an original idea, for it was the
offspring of the theory of evolution which was at that time in vogue.
Public-domain text, read in full here on John Shaqi.
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