276 DIFFERENCE BETWEEN OPSONINS AND ANTIBODIES 



in blood never exceeds twice the normal and the actual amount 

 may be much more but anything like the enormous amounts 

 which can be obtained when working with antitoxins or agglutinins 

 are never met with in the case of these bacteria at least. 



FIG. 67. SHOWING THE DIFFERENCE BETWEEN THE BEHAVIOUR OF THE 

 TRUE ANTIBODIES (DOTTED LINE) AND OPSONIN TO SUCH ORGANISMS AS 

 TUBERCLE (LOWER LINE) WHEN SUCCESSIVE INJECTIONS ARE GIVEN. 

 (Schematic.) 



FIG. 68. SUMMATION OF NEGATIVE PHASES IN OPSONIN FORMATION AS THE 

 RESULT OF INJECTIONS IN RAPID SUCCESSION. (Schematic ) 



When injections are repeated during the negative phase a 

 phenomenon of summation may be met with, as Wright first 

 pointed out. Here the first injection may lower the index, and 

 the second and third lower it still more, until a very low figure is 

 reached. A phenomenon similar to this may be seen after the 

 injections of toxins (Fig. 68). 



