organism (6104) is not taken up by the rabbit leucocytes and guinea-pig^ 

 leucocytes in blood, neither is this organism destroyed or killed by the 

 leucocytic exudate and suspensions of leucocytes from these animals in 

 blood or fresh serum. The avirulent organism (300) is ingested by the 

 leucocytes in blood and in serum but not by washed leucocytes in Na Q 

 solution or in heated serum unless the cocci have been treated before- 

 hand with fresh unheated serum (sensitized). Similarly this organism 

 is destroyed by suspensions of leucocytes in blood or serum but not by 

 suspension of washed leucocytes in NaCl solution or heated serum. The- 

 washed leucocytes do however destroy the sensitized avirulent organisms. 



EXPERIMENTS WITH ORGAN CELLS. 



It seems quite reasonable to suppose that the organ cells might play 

 an important part in the protection of the body against invasion by 

 streptococci ; and with this point in mind the following experiment was 

 carried out: 



Experiment. Two guinea-pigs, A and B, were bled to death and' 

 the blood collected under aseptic precautions. The organs were now care- 

 fully removed from the body, placed in sterile glass dishes and rubbed 

 up: (A) with guinea-pig's serum, and (B) with defibrinated guinea- 

 pig's blood. The organs and blood were not allowed to become cold. 



TABLE 4. 



SHOWING THE EFFECT OF THF SUSPENSIONS OF ORGAN CELLS OF GriNEA-PK.S ON 



STREPTOCOCCI. 



Strepto- Iinmedi- 



cocci. ately. ' lirs. IN hrs. 



B104 -+- Defibrinated blood 1800 HHM 1 500- 



B104 Blood + muscle 2000 8000 Many 



B104 Blood -I- spleen 1900 Many Many 



B104 Blood + liver 1800 Many Many 



B104 Blood -f- kidney 1900 Many Many 



B104 Blood +Hdrena1 1500 Many Many 



B104 Blood + lymph gland 1500 0000 Ma ny 



300 Blood -f bone marrow 2500 lOoo Many 



300 Serum 3SOO :;75o (5000 



300 Serum -j- leucocytes 2700 1800 1500 



300 Serum + spleen 2800 50OO Many 



300 Serum -j- liver 2000 12000 Many 



300 Serum + kidney 2400 12000 Many 



Control liver + serum " !> 



Control ppleeu + serum 0- 



The strain of streptococcus B104 used in this experiment has not been passed 

 through rabbits and has lost its virulence. 



