in the blood stream that there resulted a marked decrease in 

 the opsonins for staphylococci. Yet this enfeebled animal in 

 its losing struggle against a streptococcus infection was able 

 to react against a secondary infection of staphylococcus in a 

 manner so vigorous as to completely banish these bacteria from 

 the body. During this time there was an unmistakable increase 

 in the opsonic index for stapnylc coccus, and at the time of 

 death this index was only slightly below the normal. The op- 

 sonic increase is ,^iven in the following table: 



It would s-^em tnat the body reacted against the secon- 

 dary infection in -n independent manner, and that the recovery 

 from one infection and death from cmother occured, by chance, at 

 the same time. 



Experiment 12. — In this experiment an attempt was made 

 to reproduce experimentally the spontaneous infections described 

 in Experiment 11. An adult female cat. No. 38, was injected 

 intravenously with 3cc of an 18 hour broth culture made directly 

 from the heart's blood of a cat dying of the epidemic strep- 

 tococcus infection. I'he cat came down with the cnaracteristic 

 sjmiptoms and died after 72 nou. s. The extent of emaciation 

 and collapse Vi/as not as marked as in the .receeding cases. 



The routine determinations are recorded in the accom- 

 panying table 



C39) 



