SCIENTIFIC PROCEEDINGS. 



Abstracts of Communications. 



One hundred eighteenth meeting. 



New York Post-Graduate Medical School, November 16, 1921. 

 President Wallace in the chair. 



36 (1783) 



Alcohol and white rats: a study of fertility. 



By E. CARLETON MACDOWELL. 



[From the Station for Experimental Evolution, Cold Spring Harbor, 



N. Y.] 



This paper deals with the effect of alcohol fumes upon the size 

 and number of litters produced by white rats and their descendants. 

 Details of the administration of the alcohol have been published. 1 

 The treatment was given from the age of 28 days through the lives 

 of the rats, with the exception of the females on the 28 days fol- 

 lowing the birth of a litter. After mild initial doses, each rat was 

 left in the fume tank each day until it was completely anesthetized. 

 Brothers and sisters of the treated males and females were used as 

 controls. The ma tings were all between treated males and treated 

 females or their descendants, and between the controls. Each 

 group of test matings in each generation had its own control group 

 raised at the same time and under the same conditions of environ- 

 ment. The data came from four main groups of rats: those 

 treated, their treated children, their untreated children, and their 

 untreated grand children from the untreated children. 



Size of Litters. — The average size of all the litters produced by 

 the treated rats was 10 per cent, less than the control average. 

 Nine pairs of treated offspring from these treated rats gave litters 

 that were 10.3 per cent, smaller than their control litters. Ten 

 pairs of untreated rats from the treated parents gave litters that 

 were 11. 2 per cent, smaller than the controls. And eleven pairs 



1 MacDowell and Vicari, Jour. Exp. Zodl., 192 1, xxxiii, 209. 



69 



