of genius, like Camerarius and Koelreuter, who however surpassed them both in boldness of conception and was therefore
even less understood by his contemporaries and successors., than
they had been by theirs. The conclusions, to which his investigations led him, were so surprising, they suited so little
with the dry systematism of the Linnaean school and with
later views on the nature of plants, that they had become quite
forgotten when Darwin brought them again before the world
and showed their important bearing on the theory of descent.
As Camerarius first proved that plants possess sexuality, and
Koelreuter showed that plants of different species can unite
sexually and produce fruitful hybrids, so now Sprengel showed
that a certain form of hybridisation is common in the vegetable
kingdom, namely the crossing of different flowers or different individuals of the same species. In his work, 'Das neu entdeckte Geheimniss der Natur in Bau und Befruchtung der Blumen,' Berlin, 1793, he says at page 43: 'Since very many flowers are dioecious, and probably at least as many hermaphrodite flowers are dichogamous, nature appears not to have
intended that any flower should be fertilised by its own
pollen.' This was however only one of his surprising conclusions; still more important perhaps was the view, that the
construction and all the peculiar characters of a flower can
only be understood from their relation to the insects that visit
them and effect their pollination ; here was the first attempt to
explain the origin of organic forms from definite relations to
their environment. Since Darwin breathed new life into these ideas by the theory of selection, Sprengel has been recognised as one of its chief supports.
It is highly interesting to read, how this speculative mind
the second part of his famous work; his publisher did not even give him a copy of the first part. Natural disgust at the neglect with which his work was treated made him forsake botany and devote himself to languages. He died in 1816. One of his pupils wrote a very hearty eulogium on him in the 'Hora' of 1819, p. 541, which has supplied the above facts.
