HEMOPHILIA 421 



not attacked by night-blindness showed almost normal refraction. If we con- 

 sider the genealogy of this family, which is shown under Fig. 25, it is noted 

 first that the ancestor of the family, Andreas St., born in 1750, was healthy. 

 Whether he was the son, or his wife the daughter or sister, of a person who 

 had night-blindness, cannot now be ascertained. His three sons were all 

 night-blind, but did not marry. His daughter, Mrs. Lehmann-Steiner, unfor- 

 tunately became the ancestress for the further transmission of the disease. 

 She transmitted the affection to her two sons; of her two daughters, one 

 (Mrs. Vogel-Lehmann) transmitted the disease to two of her four sons. 

 Therefore, not all of the sons are night-blind, as in the second and third gen- 

 erations, but only one-half of them; of the four married daughters only two 

 became conductors for the following generation, and of these two only one 

 transmitted the disease to her two sons, while the other (Mrs. Frey) had three 

 sons of whom one only showed the disease. The four daughters of Mrs. Frey 

 have very large families, but the sixth generation of this line remains com- 

 pletely exempt from the disease. 



Therefore a decided diminution of the disease is here apparent, as had been 

 previously observed by Cunier in the year 1838. The condition is different in 

 the families where the disease is transmitted from the male side, i. e., from the 

 affected father through the daughter to the grandchild: Walter Keifer, the 

 grandchild of Adolf Vogel, is a descendant of the sixth member, and inherits 

 the disease to so high a degree that he can scarcely go about alone at night. 

 In the fifth generation also there is a grandchild affected by night-blindness, 

 in whose line the affection perhaps may be propagated; therefore the disease 

 may not rapidly die out in this family, but it is certainly on the decline. It 

 would be interesting to know the further fate of the family; whether a mem- 

 ber of the family with night-blindness in a manifest or latent form niay, for 

 some unknown reason, become the progenitor of a race that will show a decided 

 tendency, or whether the disease will gradually disappear. The question also 

 interests us whether the affection may arise spontaneously without any hered- 

 itary predisposition, and may then be only accidentally transmitted in this or 

 that way, or whether such sporadic cases as are actually observed depend 

 upon a poorly maintained family tradition, or upon insufficient observation 

 of the individual members of the family. To decide this, further accurate 

 professional observations will be necessary. 



The hereditary form of hemophilia is unquestionably and by far the most 

 frequent, but a so-called congenital form of the disease also appears to exist. 

 We understand by this that from the marriage of healthy persons originating 

 from healthy families children are born who are bleeders, and from these latter 

 the disease may be further transmitted. 



The importance of marriage between Mood relations in favoring the devel- 

 opment of hemophilia has been emphasized, as well of psychical influences 

 (such as fright, anger) during pregnancy. Up to this time there is no sci- 

 entifically founded theory in support of these views. 



Spontaneously, and without heredity, the disease certainly occurs only in 

 a very small number of cases, and in these the twenty-second year of life is 

 looked upon as the absolute limit of time up to which persons previously 



