INHERITANCE OF MENTAL DEFECTS AND DISEASE 41 
gives 35 per cent, and the 56 per cent of my table coincides with 
Spratling’s record in 1,100 cases.” 
The gravity of the disease (it is seldom curable) and its not 
infrequent connection with some of the worst crimes of violence, 
render the subject of its mode of transmission of especial impor- 
tance. The first serious attempt to show that epilepsy is inherited 
according to Mendel’s law was made by Davenport and Weeks 
who followed up the pedigrees of many of the inmates of the New 
Jersey State Village for Epileptics at Skillman, N. J. The pedi- 
grees were obtained mainly by field workers and the data were 
analyzed according to the assumption that the matings fell into 
the classes which might be expected to occur in simple Mendelian 
inheritance. We quote the principal conclusions of the investiga- 
tion: “Epilepsy and feeble-mindedness show a great similarity of 
behavior in heredity supporting the hypothesis that each is due to 
the absence of a protoplasmic factor that determines complete 
nervous development.” 
“When both parents are either epileptic or feeble-minded all 
their children are so likewise. 
“The conditions named migraine, chorea, paralysis, and ex- 
treme nervousness behave as though due to a simplex condition 
of the protoplasmic factor that conditions complete nervous 
development. .. . 
“When such a tainted individual is mated to a defective about 
half the offspring are defective. 
“When both parents are simplex . . . and ‘tainted’ about 
one-quarter (actually 30 per cent) are defective. 
“Normal parents that have epileptic offspring usually show 
gross nervous defect in their close relatives. 
‘While we recognize that ‘epilepsy’ is a complex, yet there is a 
classical type numerically so preponderant that, in the mass, 
‘epilepsy’ acts like a unit defect.” 
Only one instance is given in which both parents were epileptic 
and it happened that both were feeble-minded also. Of their four 
children one was feeble-minded and died before 14; but the other 
3 all developed epilepsy. In a subsequent paper by Weeks two 
