1. The hemolysis is not observed in the agglutinated red blood cells with sufficient complement, this phenomenon increased after hemagglutination occurs. 2. The hemagglutination does not occur by non salt medium (9% cane sugar), and so the inhibition of hemolysis not recognized. 3. Therefore it is desirable by hemolysis that all component (hemolysin, red blood cell and complement) in the same time mixed or that hemolysin and red cell in cane sugar medium and then complement added.