THE punctate basophilia in erythrocytes occurring in association with lead poisoning has been interpreted in different ways and its origin still remains unknown. Since the various interpretations have been thoroughly dealt with in several text-books and monographs1–4 they will not be repeated here. It must be emphasized, however, that disagreement exists as to whether punctate basophilia originates in the immature erythroblasts of the bone marrow5 or in the circulating red cells. Neither is it known whether stippled erythrocytes merely represent altered reticulocytes or polychromatic, that is, young erythrocytes.