1. Juvenile Coturnix coturnix japonica males were injected intravenously with 2, 20 or 200 mg ethyl methanesulfonate (EMS)/kg body wt; 0.2, 2 or 20 mg paraquat (PARA)/kg body wt; or 0.6, 6 or 60 mg phenylhydrazine (PHZ)/kg body wt; and hematologic variables were measured at 0 (non-injected), 24 and 72 hr post-injection. 2. EMS, PARA and PHZ-induced hemolytic anemia began within 24 hr post-injection. 3. Recovery from anemia began within 72 hr post-injection of EMS or PARA, but PHZ injected quail continued to show a marked anemia at that time. 4. EMS and PARA induced lymphocytopenia, monocytopenia and heterophilia, while PHZ induced lymphocytosis, monocytopenia and heteropenia after injection. 5. These results suggest that the anemia induced by EMS and PARA was dissimilar from that induced by PHZ, that all chemicals affected leukopoiesis and that Japanese quail can mount a marked recovery from the hematologic affects of PARA, a widely used herbicide, in a short interval after intoxication.