While engaged in the study of the opsonins there arose the following questions which have not received appropriate consideration in previous publications and which, nevertheless, are deemed important:
1. What influence has the strength of the bacterial emulsion on the phagocytic index and the percentage of phagocyting cells?
To this end an emulsion of the Staphylococcus aureus of definite strength was prepared and progressively diluted; the serum and corpuscles came from a healthy individual. The results are shown in Table 1.
In this table it will be observed that the phagocytic index and the percentage of phagocyting cells are, generally speaking, in direct proportion to the strength of the bacterial emulsion. This influence of the varying
strength of the emulsion is further shown in Table 2, in which both the opsonic bacillary index (Wright) and the percentage index (Simon) are worked out:
2. What effect has the period of incubation