‘In all early work, reliance was placed entirely upon infections with benign tertian malaria (Plasmodium vivax). Such infections are relatively harmless provided that the physical state of the patient is fairly good before the inoculation is made, and careful watch is kept on his condition... By the timely administration of appropriate treatment and by careful nursing to keep the temperature within bounds, it is usually possible to hold the infection in check and damp down its severity. Where these precautions are not taken, the case mortality has sometimes been as high as 10-14 per cent. (Meagher, 1929).' (6)