378 EVOLUTION AND GENETICS 



Decreasing Proportion of Children in the United States 

 (From Holmes, after Willcox) 



r^ Number of Children under 5 per 



^^^^ 1,000 Women 16-44 Years of Age 



1800 976 



1810 976 



1820 928 



1830 877 



1840 835 



1850 699 



1860 714 



1870 649 



1880 635 



1890 554 



1900 541 



1910 508 



This is not, in itself, a serious matter. Natural conditions tend 

 to maintenance of species rather than to their increase, and there 

 is nothing in human welfare that demands any more than the 

 maintenance of our present population. The birth rate could 

 continue to decrease in the United States for many years without 

 bringing about a decrease in population. 



Reproduction of the Unfit. A most unfortunate factor in 

 the decreasing birth rate is that the least desirable members of 

 society do not share in the common decrease. Many eugenists 

 have called attention to the fecundity of mental defectives, which 

 can probably be explained by the fact that they lead a more nearly 

 animal existence than persons of normal intelligence. Families 

 of five to eighteen children have been reported among such people 

 and even unmarried individuals contribute to their undesirable 

 stock through illegitimate unions. When associated with the 

 frequent transmission of their mental defectiveness to their off- 

 spring the fertility of these people becomes a serious prol)lem. 

 Whetham says: " Most of these children inherit the mental 

 condition of their parents, and where both parents are known to 

 be feeble-minded, there is no record of their having given iDirth 

 to a normal child. In one workhouse there were sixteen feeble- 

 minded women who had produced between them one hundred 

 and sixteen children with a large proportion of mental defect. 

 Out of one such family of fourteen, only four could be trained to 

 do remunerative work." 



The Birth Rate of the Mentally Normal. Even among the 

 classes of desirable citizens a marked disparity may be noted. 



