Abstract
(1) It was confirmed that the successive injection of cobalt into rabbits day after day brings about a definite increase of reticulocyte, followed by an increase of erythrocyte and hemoglobin content, There is no change in leukocyte count.
(2) There was observed a little difference in degree but not in nature between the polycythemia producing effects of the intravenous and subcutaneous injections.
(3) The injection of a large dose of cobalt salt at a time did not bring about an increase in erythrocyte count. Only successive, daily in-jections brought about the effect.
(4) Splanchnic nerve plays no part in the cobalt polycythemia.
(5) There was no difference in oxygen carrying capacity between . the hemoglobin of normal and polycythemic blood.
