No. 541] EFFECTS OF ALCOHOL IS HTDATINA 55 



3. When the alcohol was removed in generations XI- 

 XXII, the rate of reproduction increased noticeably in 

 the first generation and in the second generation the 

 reproduction rate equaled that of the control. 



4. Individuals of the second generation after the alco- 

 hol had been removed were no more susceptible to copper 

 sulphate than individuals which had never been sub- 

 jected to alcohol. 



5. The general conclusion is that alcohol in \ per cent., 

 4 per cent., and 1 per cent, solutions is detrimental to this 

 race of rotifers when it is subjected to it continuously for 

 many generations. The weaknesses developed by the 

 parental use of alcohol are partially eliminated in the 

 first generation after the alcohol has been removed, and 

 practically completely eliminated at the end of the second 

 generation after the alcohol has been removed. In other 

 words, the grandchildren possess none of the defects 

 caused by alcohol in the grandparents. 



6. These results in general show that alcohol in the 

 percentages used affects only the somatic tissues of the 

 animal, and if they are subjected to its influences indefi- 

 nitely, generation after generation, the race would prob- 

 ably become extinct because of its ''lowered resistance 

 power" to unfavorable conditions. However, if the alco- 

 hol is removed it is possible for the race to recover and to 

 regain its normal condition in two generations, thus 

 showing that the germ substance is not permanently 

 affected by the alcohol. 



