1. In case Trinitrotoluene (TNT) would be orally given to a rabbit, Heinz bodies may appear in most of its erythrocytes; if the dose of TNT should prove large in amount, Heinz bodies yield themselves earlier in erythrocytes; the number of Heinz body holding erythrocytes larger; and the time in which erythrocytes that hold Heinz bodies may be observed longer. 2. The administration of Foliamin, one of folic acid preparation, affects nicely toward the rabbit's anemia due to TNT administration; moreover, affects inhibittingly toward the appearance of Heinz bodies within erythrocytes. 3. Any X-irradiation over the liver region gives an influence on the appearance of Heinz bodies within the erythrocytes of a rabbit administered with TNT; in small-dose irradiation (60r), in view to the appearance of Heinz bodies within erythrocytes, improves liver function; while, a moderate dose irradiation (200r), is considered to lower it.