Just what portion of a protein stimulates the thermoregulatory center in nonspecific protein therapy is still an open subject for investigation; likewise, the degree of therapeutic activity to be ascribed to fever production is a subject of speculation. Lüke1believes that temperatures per se are not damaging factors in infections, for if in infectious diseases the temperature is artificially raised, the disease is seemingly favorably influenced. Antibodies that had gradually disappeared after an infection, or following immunization artificially produced, were again found in the serum after any procedure that increased the body temperature, whether by increasing the the external temperature, by influencing the thermal center of the brain or by injecting pyrogenic drugs. It tends to show that hyperthermia has a direct stimulating effect on the previously formed antibodies, causing the latter to mobilize freely and thus, in turn, to influence the disease processes. On the other hand, Uddgren,2as