CONTENTS xiii 



PAGB 



for the Transmissibility of Modifications. 9. Particular Evi- 

 dence in support of the Affirmative Answer. 10. As regards 

 Mutilations and the Like. n. Brown-Sequard's Experiments 

 on Guinea-pigs. 12. Negative Evidence in favour of the Affirma- 

 tive Answer. 13. The Logical Position of the Argument. 14. 

 Indirect Importance of Modifications. 15. Practical Con- 

 siderations. 



CHAPTER VIII 

 HEREDITY AND DISEASE . . . . . . . 25O 



i. Health and Disease. 2. Misunderstandings in regard 

 to the " Inheritance " of Disease. 3. Are Acquired Diseases 

 transmissible ? 4. Can a Disease be transmitted ? 5. Pre- 

 dispositions to Disease. 6. Particular Cases. 7. Defects, 

 Multiplicities, Malformations, and other Abnormalities. 8. 

 Some Provisional Propositions. 9. Immunity. 10. Note on 

 Chromosomes in Man. n. Anticipation and Intensification of 

 Disease. 12. Practical Considerations. 



CHAPTER IX 

 STATISTICAL STUDY OF INHERITANCE. . . 309 



i. Statistical and Physiological Inquiries. 2. Historical 

 Note. 3. A Hint of the Statistical Mode of Procedure. 4. 

 Filial Regression. 5. Law of Ancestral Inheritance. 6. Criti- 

 cisms of Gallon's Law. 7. Illustration of Results reached by 

 Statistical Study. 



CHAPTER X 

 EXPERIMENTAL STUDY OF INHERITANCE .... 336 



i. Mendel's Discoveries. 2. Theoretical Interpretation. 

 3. Corroborations. 4. Illustrations oj Mendelian Inheritance. 

 5. Mendel's Discovery in Relation to Other Conclusions. 6 

 Practical Importance of Mendel's Discovery. 7. Other Experi- 

 ments on Heredity. 8, Consanguinity. 



CHAPTER XI 



- HISTORY OF THEORIES OF HEREDITY AND INHERITANCE . 391 



i. What is required of Theories of Heredity and Inheritance. 

 2. The Old Theories of Heredity. 3. Theories of Pangenesis> 

 4. Theory of Genetic or Germinal Continuity. 



