CHAPTER VII 



THE TRANSMISSION OF ACQUIRED CHARACTERS 



" A right answer to the question whether acquired characters are or are 

 not inherited underlies right beliefs, not only in Biology and Psychology, 

 but also in Education, Ethics, and Politics." — Herbert Spencer. 



" II n'est pas demontre que les modifications acquises sous l'influence 

 des conditions de vie soient generalement hereditaires, mais il parait bien 

 certain qu'elles le sont quelquefois. Cela depend sans doute de leur 

 nature." — Yves Delage. [This is the opinion of one of the acutest of 

 living biologists, but we find ourselves forced to a negative position.] 



§ I. Importance of the Question. 



§ 2. Historical Note. 



§ 3. Definition of the Problem. 



§ 4. Many Misunderstandings as to the Question at Issue. 



§ 5. Various Degrees in which Parental Modifications 



might affect the Offspring. 

 § 6. Widespread Opinion in favour of Affirmative Answer. 

 § 7. General Argument against the Transmissibility of 



Modifications. 

 § 8. General Argument for the Transmissibility of Modi- 

 fications. 

 § 9. Particular Evidences in support of the Affirmative 

 Answer. 

 § 10. As regards Mutilations and the Like. 

 § 11. Brown-Sequard's Experiments on Guinea-pigs. 

 § 12. Negative Evidence in favour of the Affirmative Answer. 

 § 13. The Logical Position of the Argument. 

 § 14. Indirect Importance of Modifications. 

 § 15. Practical Considerations. 



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