CHAPTER V
| The Theory of Natural Selection (continued) | [129] |
| – Objections to the Theory of Natural Selection | [129] |
| – Sterility between Species | [147] |
| – Weismann’s Germinal Selection | [154] |
CHAPTER VI
| Darwin’s Theory of Sexual Selection | [167] |
| – Sexual Selection | [167] |
| – General Criticism of the Theory of Sexual Selection | [213] |
CHAPTER VII
| The Inheritance of Acquired Characters | [222] |
| – Lamarck’s Theory | [222] |
| – Darwin’s Hypothesis of Pangenesis | [233] |
| – The Neo-Lamarckian School | [240] |
CHAPTER VIII
| Continuous and Discontinuous Variation and Heredity | [261] |
| – Continuous Variation | [261] |
| – Heredity and Continuous Variation | [270] |
| – Discontinuous Variation | [272] |
| – Mendel’s Law | [278] |
| – The Mutation Theory of De Vries | [287] |
| – Conclusions | [297] |
CHAPTER IX
| Evolution as the Result of External and Internal Factors | [300] |
| – The Effect of External Influences | [300] |
| – Responsive Changes in the Organism that adapt it to the New Environment | [319] |
| – Nägeli’s Perfecting Principle | [325] |