194 CHARLES R. STOCKARD AND GEORGE N. PAPANICOLAOU 



large average litter. With a large average litter the sex-ratio 

 should be very low as in the female lines. We could only avoid 

 this difficulty by assuming that the control lines are out of the 

 consideration, since the other sex-ratios being discussed are all 

 shown by modified alcoholic groups among which entirely dif- 

 ferent conditions obtain from those existing in the control. 

 Whereas there are reasons for such a position, it would seem 

 preferable at present to admit that the case of the control is a 

 real objection. And such an objection would serve to indicate 

 that while a higher mortality on the part of the female embryos 

 in the alcoholic groups might actually exist, yet it accounts only 

 in part for the peculiar sex-ratios found. A recognition of the 

 normal record also makes it difficult to account for the very 

 low sex-ratios of the female lines. Here the early prenatal mor- 

 tality was low on the basis of the average size litter, but if any 

 early prenatal mortality did occur it could not have been partial 

 to the female embryos, but must on the contrary have been 

 confined almost totally to male embryos or else a sex-ratio could 

 never fall 25 below the control. Is it possible that wherever a 

 treated male is concerned, as in the male columns and the double 

 columns of table 6, there is a high early prenatal mortality among 

 the female embryos, and on the other hand where only a treated 

 female is concerned there is a high early male mortality? It is 

 difficult to believe so, and therefore differences between the early 

 mortalities of the sexes can, on our present data, only partially 

 explain the sex-ratios found in table 6. This l,eads to a final ex- 

 planation which may seem highly theoretical, yet it does have a 

 basis of fact. 



In an earlier communication (Stockard and Papanicolaou, '16), 

 we presented some evidence which seemed to indicate a possi- 

 bility that the action of the alcohol treatment not only differed 

 in its effects upon the two sexes treated, but also acted differently 

 on the two groups of spermatozoa in the male, the so-called 

 male-producing and female-producing sperm. 



We suggested that the action of the treatment was more se- 

 vere on the germ cells of the male than on those of the female; 

 in other words, that the spermatozoa were more susceptible 



