20 



THE FEEBLY INHIBITED. 



TABLE 8. Distribution of nomadism (W) in the offspring when the family history of each 

 parent is little known or at least shows no other case of nomadism (class 6) Continued. 



VI. INHERITANCE OF THE NOMADIC TENDENCY. 



1. HYPOTHESIS. 



The first outstanding fact that a study of the tables reveals is that 

 nomadism is found prevailingly in the male sex. Thus in the principal 

 fraternities of our tables there are 168 cases of male nomadics to 15 of 

 female nomadics. This fact leads one to formulate the hypothesis that 

 nomadism is a sex-linked trait. Now, a simple recessive sex-linked 

 trait fulfills the following conditions in heredity : 



(1) The tendency is ordinarily traced through the maternal side; 

 it is carried by the maternal germ-cells, though the mother may not 

 show the trait somatically. But the tendency does show itself, usually, 

 either in the mother's father or in the mother's mother's father, and, in 

 the latter case, also in the mother's brothers. 



(2) Half of the sons and none of the daughters derived from such a 

 "tainted" mother married to a normal man will show the nomadic 

 tendency. 



(3) If the mother is somatically nomadic and the father not, all of 

 the sons are nomadic. 



(4) If both parents are nomadic, all of the children, both sons and 

 daughters, are nomadic. 



(5) If the father is nomadic and there are nomadic offspring, then 

 half of the sons and half of the daughters are nomadic. 



