INHERITANCE OF MENTAL DEFECT 71 



minded and the probable degeneracy of their offspring 

 the evidence from institutions and the opinion of 

 medical men is in substantial agreement. Dr. Tred- 

 gold, an especially experienced witness, pointed out 

 that the average number of children in the families 

 which now use the public elementary schools is about 

 four ; whereas in the degenerate families whose children 

 are passed over to the special schools, there is an aver- 

 age of 7.3 children, not including those still-born. 

 The following table was prepared to show the con- 

 dition of 150 mentally defective children with their 

 brothers and sisters. In the 150 families there were 

 1269 children born. 



The high rate of mortality is noticeable, and also the 

 fact that only one-third of the offspring were accounted, 



