THE INHERITANCE OF FAMILY TRAITS 157 



and has since spread over the country. It is remarkable be- 

 cause it contains records of female bleeders, whose occurrence 

 has been doubted by Bulloch (1911). 



The eugenic teaching that holds for practically all families 

 is clear. Sisters of bleeders should not have children. Males 

 whether bleeders or not may, so far as this trait goes, marry 

 and reproduce with impunity — their germ plasm is free of 

 taint of hemophilia. 



HemophiUa is a particularly difficult disease to control 

 in descent because it is disseminated by normal females. 

 On this account it is liable to produce a community of 

 bleeders as it formerly did at Tenna, Canton Graubunden, 

 Switzerland. Even normal females from the old world 

 families of bleeders may well be prevented from landing in 

 America. 



f. Splenic Anemia with enlargement of the Spleen. — This con- 

 dition, usually recognized as hereditary, not infrequently 

 appears in the offspring of two unaffected parents. In such 

 a family reported by Bovaird (1900) 2 children out of a 

 fraternity of 10 were affected. In a family reported by Brill 

 there were affected 3 out of 6 (Fig. 136). In both famiUes to- 

 gether there were, then, 5 out of 16. In another family, when 

 one parent is affected, of 15 children of whom details are 

 known, 5 were certainly affected, two doubtful and 8 were 

 normal. Of the two matings involved one is consanguineous 

 (Wilson, 1869, Fig. 137). Though the data are still meager 

 the result favors the view that the habihty to splenic anemia 

 is due to the absence of some factor that usually gives 

 strength, A person having or fearing such a defect should 

 marry into a normal strain. It may be added that Gossage 

 (1908, p. 321) suggests that splenic anemia is due to the 

 presence of some dominant factor so the matter must be 

 regarded as still unsettled. 



