IN A PREVIOUS REPORT1it was estimated that 98.6% of infants whose distal femoral epiphyseal ossification centers were visible on antepartum films of the maternal abdomens would be mature. This figure was based on data obtained from films of the knees of 124 premature infants and on assumptions of epiphyseal ossification center visibility based on 1,935 births. Antepartum films of the abdomen were not studied, and no comment was made regarding any difference which might exist in prediction reliability between Caucasians and Negroes. It was observed that the high percentage figure of 98.6 was heavily influenced by the large number of term infants whose epiphyseal centers were presumed to be present. Since the problem of prematurity as a possible impediment to induction of labor or elective repeat Caesarean section is ordinarily posed at the 36th or 37th week of pregnancy and not at term, it was thought that this