The observations in this work suggest that with certain doses of radioactive material, the fundamental damage in the lymphoid tissues is to the stem cell and that the damage is to the chromatin of the nuclei of these cells. The erythroid tissues are apparently less susceptible to radioactive material than the lymphoid tissues but an original anemia of secondary type from peripheral destruction may eventually be changed to one of primary type through decreased maturation of primitive cells in the marrow. The damage of lymph nodes and bone marrow leads to atrophy of these organs. The cells of the liver and thymus suffer nuclear damage of the same general character as is seen in the lymph nodes, and there is an atrophy of these organs.
The storage of the radioactive material in the bones gave rise to osteogenic sarcomata in two out of seven rabbits surviving from 11 to 19 months. A repetition of the experiment has been undertaken with more intensive studies to test the validity of the findings.