VIRILE SENTIMENT 87 



fulfilled in this case, too ? The answer is Yes. When- 

 ever normal parents have married — and in this 

 family inter- marriages between extracted normals 

 have occurred — the offspring is always normal. 

 There is altogether an offspring of one thousand six 

 hundred and sixty-three normal individuals derived 

 from the marriages of normal parents, and not a 

 single abnormal person has occurred. As far as 

 human investigation can be concerned, nothing can 

 be clearer than the meaning of such a record. The 

 segregation of the normal character, once it has 

 occurred, is complete, notwithstanding that inter- 

 marriages between extracted recessive individuals 

 have occurred. And there are cases within this 

 family where this pure breeding has extended con- 

 tinuously for seven generations. There is nothing 

 to suggest that the recessive character will not con- 

 tinue so to breed for indefinite generations. 



When we examine the records of the offspring 

 derived from the marriage of abnormal with normal 

 persons (that is, marriages of the type D R x R R), 

 we find the Mendelian expectation fulfilled in that the 

 expected two types, i.e., the night-blind person and 

 the normal person, are present. But, however, the 

 expected equality of the two is widely departed 

 from. There are three hundred and sixty-four 

 persons in the disease-bearing branches of the family, 

 and it is expected that half of these will show the 

 disease, and that the other half will be healthy. 

 The expected proportion is, therefore, in round 

 numbers 182 : 182. The actual result is 135 : 229, 



