| The Bee as a Member of a Social Unit |
| The Way of Life of Bees and their Adaptability to Environment |
| Why Bee Breeding is an Exceptional Case |
| The Effects of Parthenogenesis |
| The Pedigree of the Honeybee |
| The Significance of Multiple Mating |
| The Advantages and Disadvantages of Inbreeding |
| Mendel's Laws of Heredity |
| Racial Purity in the Light of these Laws |
| The Application of Mendelism to the Honeybee |
| Chromosomes and Reduction Division |
| The Reciprocal Influence of the Genes |
| Results secured in the crosses indicated |
| Polymeral Transmission |
| Linked Characteristics |
| The Limitations Imposed by Heredity |
| Mutations |
| Synthesising New Combinations |
| The Limits Imposed on Us |
| Sex Determination |
| A Word of Warning about Mere Theory |