CHAPTER I.

History of the Sexual Theory

1. From Aristotle to R. J. Camerarius 376

2. Establishment of the Doctrine of Sexuality in Plants by R. J. Camerarius, 1691-1694 385

3. Dissemination of the New Doctrine; its Adherents and Opponents, 1700-1760 390

4. The Theory of Evolution and Epigenesis 402

5. Further Development of the Sexual Theory by J. G. Koelreuter and Konrad Sprengel, 1761-1793 406

6. New opponents of Sexuality and their refutation by Experiments, 1785-1849 422

7. Microscopic Investigation into the Processes of Fertilisation in the Phanerogams, the Pollen-Tube and Eggs, 1830-1850 431

8. Discovery of Sexuality in the Cryptogams, 1837-1860 436