SUMMARYThe life history ofCercospora DavisiiEllis&Ev. onMelilotasspp. appears to have been completed by the finding of the spermogonial and the ascigerous stage. The development of the spermogonial stage appears to be dependent upon a temperature below 20 degrees C. The ascigerous stage found on overwintered stems is described asMycosphaerella Davisii. Evidence of resistance to stem blackening by this fungus is recorded.