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THE AMERICAN NATURALIST [Vol. L 



had the power to transmit the defective condition to their 

 young, and such F 2 young were equally if not more de- 

 fective than the immediate offspring of the treated 

 animals. 



In 1914 in a short abstract Stockard showed further 

 that the offspring from F 2 individuals were apparently 

 more defective than their parents and were often grossly 

 deformed. One case was recorded of the occurrence of 

 a litter of two F 3 animals, both of which were extremely 

 weak and neurotic, showing a condition suggesting paral- 

 ysis agitans, and further than this the two animals were 

 typical anophthalmia monsters. The eyes were com- 

 pletely absent, no optic nerve or optic chiasma or visible 

 optic tracts along the tuber cinereum could be found on 

 a careful gross examination of the brain. The two ani- 

 mals were produced by parents (F 2 ) that had never been 

 treated with alcohol, the four grandparents (F x ) had also 

 not been treated, while the three great grandfathers had 

 been alcoholized and the three great grandmothers were 

 normal untreated individuals. 



Defective eyes and absence of one eye or both eyes have 

 been frequently met with in the experiment, as well as the 

 peculiar nervous condition, and these symptoms are to be 

 considered indicative of the injury or change induced in 

 the male germ cells by the experimental treatment, which 

 in the above case was transmitted through three genera- 

 tions. No question could remain as to the action on the 

 germ cells, as only male ancestors had been treated; 

 every female of the line was an untreated animal. 



This abstract called attention to the fact that there was 

 a tendency for the results to differ in subsequent genera- 

 tions from treated males as compared with the descend- 

 ants of treated females— not enough data were then pres- 

 ent to offer any explanation of these differences and a 

 consideration of them will be undertaken in the present 

 paper. 



At that stage of the experiment it was also difficult to 



