Southern New Guinea (SNG) can be defined as the lowland area enclosed by the Digul River to its northwest, the Fly River to its northeast, and the waters of the Arafura Sea, the Torres Strait, and the Coral Sea to its south. Linguistically, it is one of the least known parts of Melanesia. Yet the glimpses we already have are enough to see that this zone has among the highest levels of linguistic diversity in New Guinea (see Maps 6.1 and 6.2), arguably only exceeded by those found in the Sepik and the north coast.