In the present report are presented the results of the clinical and statistical observations conducted on the hemomyelogram of various leukemias occurring in the Chugoku-Shikoku District, with a special reference to the comparative studies carried on the bone marrow of patients treated in our department, handling the cases in which bone-marrow tissue culture was conducted and those without the tissue culture separately. It is to be noted that chronic lymphocytic leukemia is not included in the present study as the number of such cases was to small. 1. In every leukemia generally immature cells are markedly increased in number; in acute leukemia blast cells occupy the major proportion; and in chronic leukemia young leucocytes in various stag...