UY R. GREIG-SMITH. 399 



chloride containin<ij from 10 to 1-1 %. As, however, the thick- 

 ness of the bacterial suspension, the time of incuhation, and the 

 nature of the phagocytes have each a certain influence ujion the 

 results, these would have to be taken into account. 



Next to the saline, the thickness of the bacterial suspensions 

 produces the greatest variations in the curves; the thicker the 

 suspensions, the greater are the divergences from the straight 

 line. The greater the pha^^'ocytosis, the more does the high 

 saline-content of the normal serum make itself manifest by 

 increasing the convexity of the curves. 



A local slight rise and fall (a " hump ") is generally obtained 

 at the ^ and ^ dilutions. 



The higher phagocytic indices that are obtained upon diluting 

 serum with saline, are occasioned by the total salinity of the 

 mixture, in which phagocytosis occurs, being lowered to a density 

 which is more favourable for phagocytosis. 



Summary. — The regularity of the phagocytosis of staphylococci, 

 in the presence of normal serum progressively diluted, is influ- 

 enced by the following in their order, the first being the most 

 important. 



1. The strength of the saline. 



2. The thickness of the bacterial suspension. 



3. The nature of the phagocytes. 



4. The duration of the phagocytosis. 



