PARENTAL ALCOHOLISM AND THE PROGENY 291 



quantitative data than he has yet pubUshed in order to reach a 

 critical opinion. Dr. Stockard informs me, since the above was 

 written, that in his opinion figure 6 would more fairly represent 

 the guinea-pig case. 



Now in the case of the fowls in these experiments we may 

 suppose that the germ cells are more resistant so that the same 

 intensity P produces an effect such as that shown in figure 7. 

 Here relatively many more of the gametes are capable of form- 

 ing normal zygotes {a'), and the h' band is much narrower, indi- 

 cating that relatively few defectives are formed. The normal 

 offspring produced are of superior quality because the alcohol 

 has acted as a selective agency, putting completely out of com- 

 mission all the poorer grades of germ cells and yet not being 

 sufficiently intense to injure the best grades. 



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Fig. 7 For explanation see text. 



In the case of the guinea pigs the selective agent, on this 

 hypothesis, acts with such great intensity that, having put the 

 poorer grades of germ cells out of physiological commission, it 

 also injured all the best grades to such a degree that they pro- 

 duced abnormal or defective offspring. 



Elderton and Pearson's results would appear to resemble the 

 fowl results most closely. Figure 7 might be taken on this 

 hypothesis to represent the conditions in man. Alcohol would 

 appear to be a less intense germ cell selective agent in man than 

 in the guinea pig. In this connection it is interesting and 

 significant to note that Ivanov (11) found, by direct measure- 

 ment of the duration of life as evidenced by movement, that the 

 spennatozoa of the guinea pig and the rabbit possess a relatively 

 low degree of resistance to the action of ethyl alcohol. 



