HEMOPHILIA 



417 



The fact that hemophilia may be directly transmitted also by the male 

 descendants forms an exception to the rule that women, even healthy women, 

 transmit the disease, that is, act as conductors. In a family in Bremen the 

 affection was transmitted by the father to the male members through three 

 generations. Also in the bleeder family from Wald in the Canton Zurich 

 such a tendency is noted, while on the other hand, the transmission from the 

 healthy mother occurs in the sons. In this case, in the first generation that 

 showed bleeders, among 16 persons there were 7 bleeders. In the following 

 generation, among 28 members there were 16 bleeders. In the third genera- 

 tion, there was a noteworthy decrease in that this showed only 1 bleeder and 



+ + 



Fig. 23. — Genealogical Tree of a Bleeder Family. (After H. Gocht.) 

 Bleeders are shaded. 



12 non-bleeders. That from a hemophilic mother bleeders as well as non- 

 bleeders may be born is demonstrated by the following ancestral tree which is 

 taken from a communication of H. Gocht {Arch. f. Min. Chir., Bd. 59) 

 (Fig. 23). 



The disease proved itself most stubborn in a family in the little village 

 of Tenna in Graubiindten, consisting of about 170 persons, whose family tree 

 was first described by Grandidier and Vieli, and then carefully revised by 

 Hosli who eliminated many incorrect statements of the first communication. 

 Here the hereditary transmission could be followed through six or seven gen- 

 erations. However, bleeders twice married into the family, which may explain 

 the long persistence of the pathologic predisposition. Several times the dis- 

 ease skipped two generations in this family, then reappeared in the third. In 

 the direct descendancy still longer pauses occurred; but probably only the 

 severest cases have been recorded. 



The disturbances to which we may ascribe hemophilia may be designated 

 as " parahlastic," if we with His ascribe the development of the connective 

 tissue and of the blood and lymph apparatus to the parablasts in opposition 

 to the arehiblasts, this latter designation being reserved for the epithelial 

 tissues that compose the ectoderm and the entoderm. 



Although the development of the parablasts may still be questionable, 

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