SummaryExperimental osteomyelitis resembling that in human beings can be produced in nearly 100% of rabbits by infection with a suitable strain ofStaphylococcus aureusaccording to the method of Scheman, Janot and Lewin.Penicillin given in the form of a suspension in peanut oil and beeswax has a beneficial effect on acute osteomyelitis in rabbits when given within forty‐eight hours after the infection, but fails to prevent extension of the disease in all cases.Treatment with penicillin delayed for six days had no significant effect on experimental acute osteomyelitis in rabbit