130 THE TREND OF THE RACE 
types of humanity. On the other hand, those who are mentally 
defective or subnormal tend, through their lack of restraint and 
foresight, to be unusually prolific. The records of the Jukes, 
Kallikaks, Nams, Hill Folk, Tribe of Ishmael and other notorious 
defective strains show that these degenerates are distinguished 
for unusual fecundity which more than offsets their high infant 
mortality. Dr. Wilmarth in reporting on some cases of the 
transmission of mental defect has incidentally chosen cases which 
illustrate the high fecundity which is only too prevalent in this 
class: “‘Two children from one family are under our care. From 
the sheriff, who brought the children, and an intelligent neighbor, 
I learned that the mother was weak mentally. The father seldom 
worked but managed to raise his family on what he could obtain 
in other ways. Not one of the eighteen children was a desirable 
member of society. The girls drifted into disreputable lives; the 
boys were idlers and thieves with no moral sense. I know a 
couple in Pittsburgh, Pa., whose nine children were all idiots of 
low grade. A family in eastern Wisconsin, the father and mother 
are both feeble-minded; at least 7 of the 8 children are imbeciles; 
5 we have cared for. A couple in this state have nine children, all 
subnormal, and there are several, to my knowledge, in collateral 
branches of the family. One feeble-minded woman, now removed 
from the state, had by different men 18 children in 19 years, she 
alleges. I have seen only three of her children. These were 
feeble-minded and especially defective in moral sense.” 1 
1Dr. C. T. Ewart (Jour. Mental Science, 56, Oct., 1910) states that “Dr. Ettie 
Sayer, in the course of her work for the London City Council, studied the family 
history of 100 normal families and 100 families where mental defectives were found. 
The normal families averaged five in number, while families showing abnormality 
averaged 7.6, or nearly one-third as many more.” It is not altogether clear from 
the account how the average number in the normal families was arrived at. If 
100 families were chosen and the average number of children computed, it would 
not form a fair basis of comparison with the fecundity of the stocks containing 
mental defectives. Taking the mental defectives, or any lot of individuals however 
characterized, it is probable that they will be found to come from families of 
more than the average size. If we draw 100 people at random from the general 
population, we are apt to get a preponderating number from families of relatively 
large size, since these present the largest number of individuals to draw from. If 
we take 100 families and find the average number of individuals they contain, this 
