Rural schoolchildren between the ages of 6 and 18 years were screened for residual paralysis following poliomyelitis; 503 (0.85%) out of a total of 58,592 were victims. Of these, only 16 (3.8%) had received poliomyelitis vaccine, while the remainder had not been immunised. The disease had occurred before the age of 4 years in nearly 90%, the lower limbs being affected (98%) more often than the upper (2%). In the lower limbs, the quadriceps, hip adductors and tibialis anterior were frequently affected. The muscles supplied by the L4 and L5 spinal segments were most commonly involved, while those supplied by L1 and S3 were least. Some order does exist in the apparently irregular distribution of paralysis after poliomyelitis.