122 HEREDITY IN RELATION TO EUGENICS 



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Fig. 90. — Pedigree of a family with myopia. In the first generation the 

 man had myopia and strabismus while his wife was normal. Their son, II, 1, 

 had myopia and died unmarried. His normal sister married a normal man 

 and had 7 children. Ill, 1 and 2, had both myopia and strabismus; the eyesight 

 of III, 3 and 4, was defective but in what waj'^ is unknown. A normal sister, 

 III, 7, had a son with defective sight — probably myopia. From Oswald, 

 1911. Note that males only are affected and are derived only from 2 normal 

 parents. Simplex mothers indicated by heavy circles. 



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Fig. 91. — Pedigree of myopia. Members of the 3 youngest generar 

 tions were personally examined. Nearly all males of the family are myopic, 

 and none of the females, but myopia is transmitted through the female line. 

 Myopia is about the same in all cases, 10 or 12 D, with some astigmatism. 

 From Worth. The defect shows in males only and these are always descend- 

 ants of normal females. Their simplex mothers are represented by heavy 

 circles. 



