24 



heredity of natural characters and that of acquired charac- 

 ters, a conflict, in which nature must win, if art does not 

 counteract it." x 



Thus far we see that the study of heredity teaches us 

 concerning the inheritance of like qualities the dormancy 

 or suspension of qualities which may become manifest on 

 a particular occasion in the individual life or in subsequent 

 generations (as evidenced by the fact that children whose 

 likeness to their mothers is apparent at one period of their 

 lives, at another will become much more like their fathers), 

 and the combination to produce certain qualities or varia- 

 tions. I shall now briefly inquire into the so-called laws 

 of heredity empirical, no doubt, but applicable to the 

 many oddities, exceptions, and contradictory opinions 

 which complicate the question when we venture to proceed 

 from theory to individual facts, and which may all be 

 brought within the compass of the following few formu- 

 laries : 



I. Direct Heredity. 



II. Reversional Heredity, or Atavism. 



III. Collateral, or Indirect Heredity. 



IV. The Heredity of Influence. 



V. Specialised or Initial Heredity. 



De Quatrefages says : " Clearly the mathematical law of 

 heredity would be for the parent creature to reproduce 

 itself in its progeny. And perhaps this law, absolute though 

 it be, is to be found underlying all natural phenomena ; but 

 in every case it is marked by accessory circumstances by 

 the conditions amid which heredity acts. But it does not 

 only rest on theoretical considerations it rests also on facts. 

 Although subject to profound and continual disturbance, 

 1 Ribot. 



