Chapters in this book

1. Frontmatter i
2. ACKNOWLEDGMENTS ix
3. CONTENTS xi
4. CHAPTER I. INTRODUCTION 3
5. CHAPTER II. MONSTROSITIES AND TWINS 11
6. CHAPTER III. SUNDRY FACTS CONCERNING TWINS 18
7. CHAPTER IV. A REVIEW OF SOME EXPERIMENTAL STUDIES UPON TWINS 39
8. CHAPTER V. OUR EXPERIMENTAL APPROACH AS RELATING TO HEREDITY AND ENVIRONMENT: METHODS, TESTS, PROBLEMS 50
9. CHAPTER VI. DATA ON DISSIMILAR TWINS LIVING IN SIMILAR ENVIRONMENT 55
10. CHAPTER VII. DATA ON SIMILAR TWINS LIVING IN SIMILAR ENVIRONMENT 93
11. CHAPTER VIII. DATA ON SIMILAR TWINS LIVING IN DISSIMILAR ENVIRONMENTS 121
12. CHAPTER IX. RESULTS: THEIR INTERPRETATION AND IMPLICATIONS 139
13. CHAPTER X. CONCLUSIONS 147
14. INDEX 151