#Negrilloes#: _Akka_; _Wochua_; _Dume(?)_; _Wandorobbo(?)_; _Doko(?)_; _Obongo_; _Wambutte (Ba-Mbute)_; _Ba-Twa_. #Bushmen#: _Family groups_; _no known tribal names_. #Hottentots#: _Wa-Sandawi (?)_; _Namaqua_; _Griqua_; _Gonaqua_; _Koraqua_; _Hill Damaras_. * * * * * In ethnology the only intelligible definition of a Bantu is a full-blood or a half-blood Negro of Bantu speech[225]; and from the physical standpoint no very hard and fast line can be drawn between the northern Sudanese and southern Bantu groups, considered as two ethnical units. Thanks to recent political developments in the interior, the linguistic divide may now be traced with some accuracy right across the continent. In the extreme west, Sir H. H. Johnston has shown that it coincides with the lower course of the Rio del Rey, while farther east the French expedition of 1891 under M. Dybowski found that it ran at about the same parallel (5 deg. N.) along the elevated plateau which here forms the water-parting between the Congo and the Chad basin. From this point the line takes a south-easterly trend along the southern borders of the Zandeh and Mangbattu territories to the Semliki Valley between Lakes Albert Edward and Albert Nyanza, near the equator. Thence it pursues a somewhat irregular course, first north by the east side of the Albert Nyanza to the mouth of the Somerset Nile, then up that river to Mruli and round the east side of Usoga and the Victoria Nyanza to Kavirondo Bay, where it turns nearly east to the sources of the Tana, and down that river to its mouth in the Indian Ocean. At some points the line traverses debatable territory, as in the Semliki Valley, where there are Sudanese and Negrillo overlappings, and again beyond Victoria Nyanza, where the frontiers are broken by the Hamitic Masai nomads and their Wandorobbo allies. But, speaking generally, everything south of the line here traced is Bantu, everything north of it Sudanese Negro in the western and central regions, and Hamitic in the eastern section between Victoria Nyanza and the Indian Ocean.