x jj CONTENTS. 



CHAPTER XVIII. 



PAGE 



Special Physiology of Sex and Reproduction - - 221-243 



I. The continuity of germ-plasma. 



II. Sexual maturity. 



III. Menstruation. 



IV. Sexual Union. 



V. Parturition. 



VI. Early nutrition. 

 VII. Lactation. 



VIII. Other secretions. 



IX. Incubation. 



X. Nemesis of reproduction. 



XI. Love and death, or organic immortality. 



CHAPTER XIX. 



Psychological and Ethical Aspects - - - 244-260 



I. Common ground between animals and men. 



II. The love of mates. 



III. Sexual attraction. 



IV. Intellectual and emotional differences between the 



sexes. 



V. Love for offspring. 



VI. Criminal habit of the cuckoo. 



VII. Egoism and altruism. 



CHAPTER XX. 



Laws of Multiplication ------ 261-275 



I. Rate of reproduction and rate of increase. 



II. History of discussion. 



III. Spencer's analysis ; individuation and genesis. 



IV. Spencer's application to man. 



V. General statement of the population question. 



VI. Sterility. 



CHAPTER XXI. 



The Reproductive Factor in Evolution - - 276-289 



I. General history of evolution. 



II. The reproductive factor so far as hitherto recognized. 



III. Suggested lines of further construction. 



