AN EXUBERANT TERMINOLOGY 109 



2. Certain Necessary Saving Clauses 



A discussion of the different modes of hereditary resemblance 

 is somewhat hampered by an exuberant terminology, and by 

 the fact that different authors have sometimes used the same 

 term in different ways. We read of inheritance being unilateral 

 and bilateral, unisexual and bisexual, blended and conspired, 

 neutralised and combined, direct and collateral, atavistic and 

 progressive, reversionary, exclusive, particulate, alternative, 

 Mendelian, and so on. With the progress of investigation the 

 redundant terminology is being pruned. Thus, many modes of 

 inheritance which seemed at first discrepant are now recognised 

 to fall within Mendelian formulation. 



We have seen that cases of apparently very complete hereditary 

 resemblance may be illusions due to our inability to appreciate 

 the differences that really exist ; but on the other hand, we must 

 guard against the error of supposing that the frequently con- 

 spicuous differences between offspring and their parents neces- 

 sarily mean an incompleteness in the inheritance itself. The 

 fact that the resemblance often reappears in the third generation 

 shows that the incompleteness is often not in the inheritance, 

 but simply in its expression. The characters were probably 

 there in posse in the germinal matter, but they were neutralised, 

 kept latent, silenced we can only use metaphors by other 

 characters, or else they never met with the stimulus necessary 

 for their expression in development. We can imagine the son 

 of a lavish millionaire reacting to plain living, the superficial 

 inference that the money had been lost, and the contradiction 

 of this in the third generation. 



Similarly, when a male offspring is compared with the mother, 

 a female offspring with the father, it is important to bear in mind 

 that the difference in sex may account for some of the apparent 

 differences in detailed characters. Through functional cor- 

 relation, the differentiation of sex may bring about the non- 



