688 OPSONISATION FROM A BACTERIAL POINT OF VIEW, ETC., 



fell slowly stepwise. In three counts of a test in which the 

 indices were very close, the curves were quite different one from 

 the other. In other cases no regularly rising and falling curve 

 has been obtained. No indication, therefore, as to the reliabilit)^ 

 of a count can be obtained from its graphic representation. 





Bacteria in 



Cocci per leucocyte. 



Corpuscles in 



Duration of phagocytosis. 





15 min. 



30 min. 



60 min. 



Citrate, 1 per cent. 

 Saline, 9 ,, 



Citrate, 1 per cent. 

 Saline, 0"9 ,, 



15 



76 

 4-6 



3 4 

 11-6 

 10-3 



58 



0-85 „ 



55 55 )1 

 5 5 5 5 5 5 

 ) » 5 5 5 5 



0-85 „ 

 1-15 „ 

 1-55 „ 

 1-95 „ 



5-2 

 46 

 2-6 

 1-4 



6-1 

 6-0 

 4-2 

 2-6 



77 



It is clear that phagocytosis is not complete in 15 minutes, but 

 goes on steadily with the time. It was not so clear which of 

 these salt-contents is the best to employ to ensure a regularity 

 of phagocytosis. One cannot use an amount of citrate in which 

 to suspend the corpuscles smaller than 1%, for haemolysis occurs 

 when less is used and the leucocytes become everted and destroyed. 

 There was a tendency to show a greater regularity of ingestion 

 when the suspensions were incubated for 30 minutes. The high 

 salt-content did not increase the regularity of phagocytosis, and 

 this was confirmed with some later investigations with 1*5% 

 saline. 



The next experiment was made with smaller amounts of salt, 

 using a moderately rich and a moderately poor suspension of 

 bacteria. Measured and equal volumes of thick bacterial sus- 

 pension were added to measured volumes of saline of varying 

 strengths to obtain the final bacterial suspension. 



