Acquired Modifications Heritable? hi 



a white male, since black is the dominant 

 character. Of course experiments of this type 

 must be multiplied before we reach a certain 

 conclusion, but, as far as the evidence goes, it 

 looks as if the body plasm were early set off 

 from the body germ, and that the former had 

 Uttle or no effect upon the germ plasm. 



Such a conclusion is also compatible with the 

 results achieved in the experiments cited before, 

 viz., that acquired characters, which are modi- 

 fications that impress the body plasm only, can- 

 not be transmitted. To put this result in more 

 concrete manner it would mean this: that if a 

 person in whose ancestry tuberculosis had 

 seldom or never occurred should come doAvn 

 with the disease and ultimately die of it, 

 children of such an individual would be no more 

 prone to the disease as far as inheritance is 

 concerned than the children of a person who 

 has not died of tuberculosis. Conversely, this 

 would be true : that if a person in whose ances- 

 try tuberculosis was a very common cause of 

 death should, by hygienic living and wise pre- 

 cautions, avoid tuberculosis, the hereditary 



