The great plain of Sennar is mainly occupied by Hassania Arabs in the north, by Abu-Rof (Rufaya) Hamites of Beja stock in the east as far as Fazogli, and elsewhere by the negroid Funj and the group of tribes collectively known as Shangalla (the Bertat, Legas, Sienetjo, Guinus, Kadalos, &c.; see Shangalla).
They are not pure Hamites, and their physical characteristics vary considerably, showing signs of interbreeding with Galla, Afar, Arabs, Abyssinians, Bantus and Negroes.
These Hamites brought with them a measure of Egyptian civilization, cattle, and the arts of metallurgy, pottery and other adjuncts to neolithic civilization.
The chief genera are Hamites, Baculites, Crioceras, Olcostephanus and certain Trigoniae.
Practically the rest of Africa, from the southern fringe of the Sahara and the upper valley of the Nile to the Cape, with the exception of Abyssinia and Galla and Somali-lands, is peopled by Negroes and the " transitional " tribes to which their admixture with Libyans on the north, and Semites (Arabs) and Hamites on the north-east and east, has given rise.
Of the tracts excepted, Abyssinia is inhabited mainly by Semito-Hamites (though a fairly strong negroid element can be found), and Somali and Galla-lands by Hamites.
The Negroid peoples, which inhabit the vast tracts of forest and savanna between the areas held by Bushmen to the south and the Hamites, Semites and Libyans to the north, fall into two groups divided by a line running from the Cameroon (Rio del Rey) crossing the Ubangi river below the bend and passing between the Ituri and the Semliki rivers, to Lake Albert and thence with a slight southerly trend to the coast.
This foreign element cannot be identified with certainty, but since the Bantu seem to approach the Hamites in those points where they differ from the Negro proper, and since the physical characteristics of Hamites and Semites are very similar, it seems probable that the last two races have entered into the composition of the Bantu, though it is highly improbable that Semitic influence should have permeated any distance from the east coast.
In the northern zone this check is absent, and the number of more essentially pastoral peoples, such as the eastern Hamites, Masai, Dinka, Fula, &c., correspondingly greater.
The Horn of Africa appears to have been the centre from which the Hamites spread, and the pressure they seem to have applied to the Negro tribes, themselves also in process of expansion, sent forth larger waves of emigrants from the latter.
Thus those qualities, physical and otherwise, in which the Bantu approach the Hamites gradually fade as we proceed westward through the Congo basin, while in the east, among the tribes to the west of Tanganyika and on the upper Zambezi, " transitional " forms of culture are found.
Certain of the Negro tribes had retired to the swamps of the Nile, and had become somewhat specialized, both physically and culturally (Shilluk, Dinka, Alur, Acholi, &c.)., These had blended with the Hamites to produce such races as the Masai and kindred tribes.