Abstract : The results indicate that the high content of reduced glutathione constitutes a characteristic of the reticulocyte, while the still young but no longer reticulated red blood corpuscles reveal a glutathione content which does not differ from that found in the mature erythrocyte. These observations agree with those made by other authors, according to when the young red blood corpuscles -- separated according to the method of fractionated ultracentrifugation -- reveal a reduced glutathione content equal to that found in mature erythrocytes.