176 THE ACTION OF THE LIVING CELL 



the kittens died within a month, although all the ani- 

 mals treated with the anticytost lived approximately 

 twice as long as the untreated ones. (Turck, 1923.) 

 The longevity of the members of both groups is sum- 

 marized below: 



Passively immunized kittens 



AGE DEATH IN 



8 weeks 17 days 



4 weeks 25 days 



4 weeks 32 days 



These experiments show that specific anticytost 

 sera afford the animals a slight degree of protection 

 from the cytost infected cages. A large series of ex- 

 periments has shown that the average life of healthy 

 kittens exposed to cytost contact is from ten to twenty 

 days, whereas if injected with anticytost serum be- 

 fore being brought into contact with cytost, they 

 usually live for a longer period, although they ulti- 

 mately succumb if not removed from such contact. 



These experiments were continued in slightly dif- 

 ferent fashion, as follows. Female cats were actively 

 immunized to cytost as above described, and allowed 

 to give birth to their offspring in cages sprayed with 

 cytost. In this case the kittens, although in contact 

 with cytost, were found to live for a considerably 

 greater period than did those born of non-immunized 

 mothers. A number of the former received injections 

 of anticytost as well, and the kittens so treated with- 

 stood the contact with cytost slightly better than did 

 those born of actively immunized mothers but re- 

 ceiving no anticytost serum. Since, however, in these 

 two groups of animals the length of life in the cages 



