VARIATIONS 77 



" sports " which reach a new position of organic equilibrium as 

 if by a leap. This is the contrast between " continuous " 

 variations small in amount, and " discontinuous " or " tran- 

 silient " variations in which a considerable step is taken with 

 apparent suddenness, without the occurrence of intermediates. 



The term variation, used concretely to denote an organic pecu- 

 liarity or idiosyncrasy, is obviously a relative term, implying some 

 standard of comparison. It is a deviation from the parental type, 

 a divergence from the mean of the stock. Thus there are different 

 degrees, or perhaps even different kinds of discontinuity. 



In many cases, a variation may be described as simply an in- 

 completeness in the inheritance or in the expression of the inherit- 

 ance. The divergence from the norm is due to the suppression or 

 inhibition of some character. This may be illustrated by a per- 

 fectly white (albino) baby, born to almost coal-black parents.* 

 If such a form became the founder of an albino race, as in the 

 case of rats and mice, we should be justified in concluding that the 

 particular material organisation which eventually leads to the 

 deposition of pigment in the body had somehow dropped out of 

 the inheritance. If the albinism was in no respect transmitted to 

 the next generation, we should be justified in concluding that the 

 structural arrangements which lead on to pigmentation had simply 

 been hindered from finding their normal expression in develop- 

 ment. 



A minus variation like albinism may be described as due to 

 an incompleteness in the inheritance or in the expression of the 

 inheritance, but there are other variations which must, so to 

 speak, bear the plus sign, for they involve the augmentation or 

 exaggeration of a character. Plus variations of this sort have 



" Its father and mother were horrified ; their fi lends and relations, 

 in fact all the villagers, were called to examine and criticise it. Why such 

 surprise ? Wky such commotion ? The answer is self-evident : the law 

 of heredity had been broken." R. W. Felkin. The vulgar mind is always 

 impressed by size and quantity ; big deviations strike the imagination, 

 and the normal occurrence of small deviations is forgottent 



