172 Eugene Rollin Corson 



types of man, with greater differentiation and a more complex 

 brain and nervous system, and where there must necessarily 

 be a greater expenditure towards individuation, — and where 

 genesis itself is more elaborate, — a lower prolificness. And, 

 on the contrary, we find, as we might expect, a higher rate of 

 prolificness among savages than among the Caucasian. But 

 this holds good of the savage only as he is found in his own 

 habitat, and under the natural conditions of which he is the 

 product. Remove him from his natural soil and climate, 

 change his conditions of life and surroundings, and throw him 

 into competition with a superior race, and in a civilization 

 which has been brought about by the growth of that race, — a 

 civilization of which he is not the product, — and he is placed 

 in an abnormal condition, and must suffer physically. And 

 this will show itself in a general deterioration of physique, in 

 a higher rate of mortality, and in a lowered rate of increase. 



We see again in certain organic forms a sort of law of com- 

 pensation where nature seems to provide for great loss of life 

 by a greater prolificness, but these two terms stand to each 

 other as correlatives rather than cause and effect. It is ver}' 

 evident that there can be no such relationship at all compar- 

 able in the higher forms of life. Here where inimical factors 

 arise which render individuation more difficult and more pre- 

 carious, the expenditure of vitality becomes greater in this 

 direction, and so much the greater the more complex is the 

 individuation ; and in like manner the genesis suffers the 

 more, the more complex its processes are. And thus a race 

 which is struggling hard to maintain individual life, and 

 which suffers in addition from an unhealthy living, and from 

 excesses of all kinds, and whose death rate is high as com- 

 pared with the more favored race, cannot maintain its normal 

 rate of increase, but, on the contrary, must show a diminished 

 prolificness. 



And another point worthy of consideration is this : It is not 

 so much a question of How many offspring ? but How many 

 matured and perfected individuals ? In other words, what is 

 the ability to maintain life when started ? And this is what 

 I mean by the vital equation. The figures I have given of 



