ABSTRACT
Apidium and Moeripithecus from the Egyptian Fayum were suggested by Gregory and by others as possible ancestors of monkeys or of Oreopithecus. The many new finds of mandibles, maxillae, isolated teeth and a considerable number of isolated postcranial bones which can be referred to the Fayum Parapithecinae, establish the relatedness of these animals to the cercopithecoid monkeys. In molar and mandibular morphology Apidium and Parapithecus species differ distinctly. Relative to tooth size, Apidium horizontal mandibular rami are typically deeper than in Parapithecus. Species of Apidium differ markedly from those of Parapithecus in that there is a clear-cut size increase in the molar series posteriorly. The upper and lower increase in the molars of Apidium are distinctly polycuspidate for a primate while in Parapithecus species, cuspules beyond the basic five are almost never present, and M3 is always distinctly smaller than M2.
