Ten adult rabbits were divided into two groups: the control rabbits, which received subcutaneous injections of 0.9% NaCl in three days; the experimental animals which received 3 mg/Kg body weight of phenylhydrazine (PHZ) subcutaneously also in three days. On the 8th day from the initial treatment the control and experimental animals were sacrificed, blood was collected to determine hematological parameters and livers were cut into small pieces. Sections were prepared by pressing the pieces onto slides which were stained with the Giemsa stain. The hematocrit and the reticulocytosis of experimental animals were 25 + 3%, and 70 + 5% respectively. In the liver sections of the PHZ treated animals we found a very rich population of immature erythroblasts. In fact proerythroblasts and basophilic erythroblasts were 19%, polychromatic and orthochromatic erythroblasts were 22% and 13% respectively. On the contrary, these cells were absent in the control livers. The lymphocyte and lymphoblast population, on the other hand, was very rich in control animals with a value of 38.8% compared to 1.62% in the anemic animals. The results clearly indicate the hematopoietic function of the liver in the anemic animals although the low percentage of orthochromatic erythroblasts with respect to their precursors suggests the ineffectiveness of the process.