ABSTRACT
It has of course been dear from very early times that there is some biological inheritance. The character of an organism depends, to some extent at least, on that of its parents. The problem of how the parental influence is exerted was for long debated in purely philosophical terms, but with the invention of adequate microscopes, and the discovery of spermatozoa and of the universal occurrence of eggs, hypotheses of a verifiable nature could be put forward. The first theory to gain general acceptance had a deceptive air of simplicity; it was supposed that the sperm (or, for the feminists, the egg) contained the complete organism in miniature, which merely had to grow to become the new adult. Elaborate theories were evolved as to how these homunculi in their turn mated and reproduced; but still more efficient microscopes soon made it clear that the eggs and sperm do not in fact contain miniature animals, and the whole elegant edifice of theory had to be abandoned. 1
