CHAP, i.] Joseph G. Koelreuter and Konrad Sprengel. 415 



of genius, like Camerarius and Koelreuter, who however sur- 

 passed 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 in- 

 vestigations 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 ent- 

 deckte 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 herma- 

 phrodite 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 con- 

 clusions ; 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 

 ' flora' of 1819, p. 541, which has supplied the above facts. 



