plants were at that time often regarded on insufficient grounds
as true seeds; Gärtner distinguished them from seeds, because
they are formed without fertilisation and yet are capable of
germination, whereas ovules become seeds capable of germination only under the influence of the pollen. He distinctly denied
the sexuality of the Cryptogams; it was not till fifty years later
that strict scientific proof was substituted in this department
of botany for vague conjecture, and it was more in the interest
of true science in Gärtner's day to deny sexuality in the Cryptogams altogether, than to take the stomata in Ferns with
Gleichen, or the indusium with Koelreuter, or the volva in Mushrooms for the male organs of fertilisation. Gärtner rightly
appealed to Koelreuter's hybrids against the defenders of the
theory of evolution; and to those who saw in the seed only
another form of vegetative bud, he said, that the bud can
produce a new plant without fertilisation but that the seed
cannot. We have already given an account in the chapters on
Systematic Botany of the services rendered by Gärtner to the
knowledge of the seed in its immature and in its mature
condition; as regards the process of fertilisation he adopted in
the main Koelreuter's view, that it is the result of the union of a male and female fluid, from which the germ-corpuscle in
the ovule is developed by a kind of crystallisation. Konrad
Sprengel also fully committed himself to this view, and was
thereby prevented from understanding the process of fertilisation in Asclepiadeae.
In Konrad Sprengel[1] we encounter once more an observer
- ↑ Christian Konrad Sprengel, born in 1750, was for some time Rector at Spandau. There he began to occupy himself with botany, and devoted so much time to it that he neglected the duties of his office, and even the Sunday's sermon, and was removed from his post. He afterward lived a solitary life in straitened circumstances in Berlin, being shunned by men of science as a strange, eccentric person. He supported himself by giving instruction in languages and in botany, using his Sundays for excursions, which any one who chose could join on payment of two or three groschen. He met with so little support and encouragement that he never brought out
