The green African monkey, Cercopithecus aethiops sabaeus, has been infected with experimental poliomyelitis after feeding artificially contaminated food. This species is also highly susceptible to intracerebral, intranasal, and intraabdominal inoculations. In one experiment with a human stool from a case of poliomyelitis, Cercopithecus was more susceptible to intranasal and to intraabdominal inoculation than Macaca mulatta.