44 HEREDITY IN RELATION TO EUGENICS 



complicated than stature and still further removed from any 

 semblance of a unit character. Moreover, it is much more 

 dependent upon conditions of life, for, as is well known, a 

 sedentary life with overfeeding and drinking tends, in persons 

 so disposed, to increase weight, even as strenuous activity and 

 dieting favor the reduction, within certain limits, of weight. 

 Despite this dependence of weight on environment we may 

 attempt to learn if it shows any trace of heredity. First, it 

 is necessary to avoid the use of absolute weights on account 

 of sex differences. So we find the mean weight of American 

 fathers and mothers and calculate our weights as deviations 

 from these means. The mean weight of fathers in our data is 

 162 pounds; of mothers 131 pounds. The range in weight of 

 fathers is from 110 to 250 pounds. The range in weight of 

 mothers is from 90 poimds to 360 pounds.^ In our study 

 we are, however, concerned less with absolute deviations in 

 weight from the average than in the deviations in corpulency 

 and so we make our starting point the weight for a given 

 stature and calculate in each case the deviation from the 

 weight that is normal for the given stature. The table of 

 normal weight that we employ is Table VI. 



Table VI 



NORMAL WEIGHT, IN POUNDS, FOR EACH INCH OF STATURE AND EACH SEX 



Inches of stature 59 60 61 62 63 64 65 66 67 



Normal weight in ( male 131 132 134 137 140 143 147 152 



pounds for ( female 107 112 117 122 126 



Inches of stature 68 69 70 71 



Normal weight in | male 157 162 167 172 



pounds for ] female 144 150 155 160 



The first result is that when both parents are slender in 

 build or of relatively light weight the children will tend all 

 to be slender. 



* This maximum occurred in a single case of our records; the next lower 



weight is 225 pounds. 



