QUESTION OF PHYSICAL DEGENERATION 241 



fertility correlated with unfitness ; (3) infertility correlated 

 with fitness ; (4) infertility correlated with unfitness. Now 

 it is obvious that only those mothers in whom the first of 

 the four correlations is found will leave any great number of 

 descendants. Hence fertility will tend to become associated 

 with the characters that are best suited to the race, fertility 

 without this association constantly tending to disappear through 

 the working of Natural Selection. Reproductive selection has, 

 therefore, to figure as a mere subordinate. The correlation 

 between height and fertility, noticed by Professor Karl Pearson, 

 is merely the machinery by which Natural Selection maintains 

 the standard of height that in long ages of struggle has proved 

 best. 



I will now put down the conclusions with regard to stature Conclusion 

 that seem to follow from the evidence obtainable. (l) Stature 

 is to a large extent a race characteristic that lasts with little 

 alteration for very long periods ; (2) each person has a poten- 

 tial stature which through unfavourable circumstances may 

 not be actualised ; (3) the increase of height observable in 

 the present day, especially in the daughters of aristocratic 

 mothers, is due to a change of environment, i.e. the potential 

 stature remains as it was ; (4) that the change of environment 

 which produces great stature is in many cases a lessening of the 

 stress of Natural Selection, and that the gain in height and even 

 bulk is often accompanied with a reduced power of bearing 

 hardship. 



If these conclusions are correct, as I hold, we have materials 

 for forming an opinion on the question of degeneration. Since 

 increase of stature is not necessarily any evidence of greater 

 potential strength or even actual strength, we cannot base any 

 arguments upon it. On the other hand, small stature in the 

 degraded population of the squalid parts of our big towns is 

 no proof of race degradation : the potential stature has not 

 suffered, and vigour is being evolved by elimination on a large 

 scale. Another phenomenon is more discouraging, viz., that 

 what would formerly have been considered luxuries, are now 

 apparently necessities for the children of the well-to-do. The 



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