294 RAYMOND PEARL 



XII. SUMMARY 



This paper deals with the effects produced upon the progeny 

 of fowls after treatment of the parents with either (a) ethyl 

 alcohol, or (b) methyl alcohol, or (c) ether. The chief results 

 may be summarily stated as follows: 



1. The proportion of fertile eggs, i.e., eggs in which a zygote 

 was formed by the union of sperm and ovum, was materially 

 reduced in the matings in which one or both individuals had 

 been treated. The higher the germ dosage index for the mating 

 the smaller was the percentage of fertile eggs found to be. 



2. The prenatal mortality, measured by the precentage of 

 embiyos (zygotes) which died before hatching to all embryos 

 formed, was materially smaller in the case of offspring from 

 matings in which one or both parent individuals were treated, 

 than in the case of offspring from untreated control parents. 



3. The post natal mortality at all ages was materially lower 

 in the case of offspring from matings in which one or both indi- 

 viduals were treated, than the average mortality of individuals 

 from untreated control parents. The only matings ol untreated 

 individuals showing as low a rate of mortality as the treated 

 matings were a selected group picked as having the very lowest 

 mortality. 



4. The sex ratio of the progeny was not sensibly affected by 

 the treatment of the parents. 



5. There was no significant difference in mean hatching weight 

 between the offspring of treated males and the offspring of 

 norma) untreated control males when both were mated to normal 

 untreated females. The slight differences which did appear 

 were of the same order of magnitude as their probable errors. 



6. Both the male and female offspring of matings in which 

 both parents were treated showed a higher mean hatching weight 

 (i.e., are heavier when hatched) than the offspring of either 

 completely normal control matings, or of matings in which the 

 father only was treated. 



7. The offspring of alcoholized parents, whatever the nature 

 of the mating, showed a higher mean adult body weight than 



