No. 590] TRANSMISSION OF DEGENERACY 



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ceive and some of the F 2 and F 3 individuals of both sexes 

 are not very prolific and in many cases are almost or 

 quite sterile. Each female is kept in a separate run and 

 the male is placed in with her just before the time of the 

 expected heat period, ovulation, and he remains in her 

 cage for from two to three weeks so as to be present at 

 the second ovulation, provided the female was not made 

 pregnant by the first mating. The ovarian cycle of the 

 guinea pig as worked out by L. Loeb seems to correspond 

 closely to what is found in mating experiences. 



After mating, the male is removed from the cage and 

 the female remains alone until the young are born. 

 These are left with the mother for about fifteen days, then 

 separated, and the female mated again. In this way the 

 normal females may sometimes give as many as four lit- 

 ters per year, but the experimental animals breed much 

 slower and it is difficult to get even three litters per year. 



Direct Effects of the Alcohol Treatment on the 

 Animals 



Several of the guinea pigs have now been treated with 

 the fumes of alcohol almost to the point of intoxication 

 for six days per week for a period of five years. This is 

 a considerable space in the life of a guinea pig, which 

 probably would not often extend beyond six or seven 

 years. 



The animals are affected by the alcohol fumes in vari- 

 ous ways ; some of them are stupefied and become drowsy, 

 while others become stimulated and excited and some- 

 times even vicious, constantly fighting and biting at the 

 other animals in the fume tank. The fumes inhaled into 

 the lungs pass directly into the circulation, so that the 

 animals show signs of intoxication very soon after being 

 Put into the tank, yet the intake of alcohol is so gradual 

 that they may remain for one hour or more without be- 

 coming totally anesthetized. 



The mucosa of the respiratory tract is considerably 



