Metatherian (marsupial) and eutherian (placental) mammals are end members of a complex, possibly common North American1-4 or, less likely, a South American5 stock that diverged before the early late Cretaceous and underwent separate adaptive radiations establishing them as the two dominant mammalian groups (subclass Theria). By the later Cretaceous, marsupials were well situated in North America3 and were also present in South America6. Their oldest occurrences in Antarctica (later Eocene 7) and Australia (Oligocene8) are artefacts of exceptionally poor fossil records of mammals on those continents and it is clear that the Metatheria must have been quite diverse in both areas (physically connected in pre-Eocene times9) very much earlier5,7. Marsupials probably did not reach Europe much before their earliest record there in the early Eocene10. The Metatheria have not been identified from Asia, nor until now from Africa. We now report the discovery of the first fossil remains of a didelphid marsupial in Oligocene rocks in North Africa. ?? 1984 Nature Publishing Group.