APPENDIX
SUMMARY OF CHAPTER II
1. Every kind of cell or other organism has a natural limit of size (dependent partly on the relation between surface and volume).
2. When that limit is reached, superfluity of nutrition and growth tends to bring about Reproduction.
3. Reproduction begins with simple division or budding.
4. Conjugation in its primitive form (as among protozoa where there is no distinction of sex) takes place between similars, and is an exchange to some degree of cell-contents.
5. It apparently affords a superior nutrition, and is a kind of Regeneration, essential to the continued health of the species, and favorable to reproduction.
6. Hunger and Love are thus related at this stage.
7. Later, conjugation takes place between dissimilars (of the same species); and the distinct phenomena of sex appear—of male and female.