MODIFICATION OF THE GERM-CELLS IN MAMMALS 



209 



The alcoholics have a higher proportion of their total mortality 

 occurring very early, so that there is a great elimination of weak 

 embryos and fetuses; this lowers their later or postnatal mortality 

 to about the normal record. In this case we have an elimination 

 or selection of individuals or zygotes rather than a germinal 

 selection. The total mortality record for the experimented 

 group is far higher than for the control and a greater percentage 

 of abnormal young are produced. The percentage of abnor- 

 malities is lower than in our former records, as is also the total 

 mortality rate. The improved mortality rate is partly due to 

 better methods of breeding and caring for the animals. Yet the 

 mortality record of the alcoholic group is very high, and when 

 corrected for the normal rate on the basis of the size litters con- 

 cerned it becomes 189 against the control as 100. Among the 



THE JOURNAL OF EXPEKI.\IENT-\.L ZOOLOGY, VOL. 26, NO. 1 



