HEREDITY. 13 



cular motion in cells " are equally hypothetical ; while 

 nothing is really known as to the action of Weis- 

 mann's " germ-plasm " or Nageli's " idioplasm." We 

 have no evidence that the protoplasm of the repro- 

 ductive cell differs from that of any other cell ; yet 

 that it has the power of transmitting from parent to 

 offspring most subtle peculiarity of mind and body we 

 know from experience, but how or why it should be 

 so endowed still remains one of Nature's profoundest 

 secrets. 



Notwithstanding the fact, however, that we cannot 

 follow Nature in all her mysterious workings, our course 

 is perfectly clear. We know that " like produces like " 

 all through Nature, and it is our duty to recognise the 

 potent influence exerted by this law in determining 

 the conformation of mind and body in the human 

 family, and endeavour to use this knowledge for the 

 benefit of the race. The hereditary transmission of 

 physical characters has been known from the earliest 

 times of which we have any record, and man has 

 benefited by this knowledge in the breeding of animals 

 from time immemorial. (He has not hesitated to apply 

 it even to the human family when the excellence of 

 the offspring was of pecuniary interest to him, as in 

 the case of slaves.) Yet, for some inscrutable reason, 

 when it becomes a personal question he ignores this 

 great fundamental law, and every year thousands of 

 children are begotten with pedigrees which would con- 

 demn puppies to the horsepond. 



What, I would ask, would be thought of the man 



