SummaryAuthors have treated six cases of leukæmia and two cases of lymphomas with urethane as proposed by Paterson and al. 3 gr. of the drug were given a day.In the cases of leukæmia a decrease of the while cells count has been observed while the amount of red cells increased at the same time. The bone marrow showed a decrease of the immature granulocytes.The spleen decreased in size. The results were not so good in the cases of lymphoma.There is no doubt that this new therapy is useful.