196 THE TREND OF THE RACE 



them because they are unable to do so or because the children 

 are unable to take mothers' milk. " These results," says Pearson, 

 "suggest that it is not the artificial feeding, but the health of the 

 mother which is the dominating factor in the mortality and 

 delicacy of the infant." The precise r61e of heredity here is, of 

 course, not revealed, but the facts indicate that it is more potent 

 than the crude data on the relation of artificial feeding to mor- 

 tality would indicate. 



Much infantile weakness, however, is the product of purely 

 somatic variability, depending upon immaturity of birth, illness 

 or misfortune to the mother and many other fortuitous conditions. 

 Of the many malformations that cause infants to die soon after 

 birth there is in relatively few cases evidence of the hereditary 

 character of the defect. Such variability serves to mask more or 

 less the true hereditary variations that may be present. Natural 

 selection would tend to eliminate the weak or imperfect individ- 

 uals whether their defects were hereditary or not, but it is only 

 to the extent that the purely hereditary variations are picked out 

 that natural selection is able to produce any racial modification. 



A high infant mortality has been considered by some investiga- 

 tors as racially advantageous in that a larger proportion of the 

 congenitally weak are eliminated. The preservation of a larger 

 proportion of the new born would save many weaklings who 

 would produce a deterioration of the vitality of the population. 

 The Eugenics Section of the American Association for the Study 

 and Prevention of Infant Mortality recognized that under present 

 conditions the efforts of the society "must necessarily work some 

 anti-eugenic results," although maintaining, as practically all do, 

 that it is an imperative duty to check infant mortality so far as 

 possible. No one seriously proposes to do away with medicine 

 and hygiene because the death rate in the adult population is to a 

 certain degree selective and it would hardly be consistent to deny 

 the benefits of medical science to the helpless period of infancy. 

 Even those who maintain that a high infant mortality is of racial 

 value generally hesitate to advocate the abolition of efforts to 

 reduce it. In reading the literature on the subject one cannot fail 



