irregular terraces.  This intermediate mountain belt is covered with luxuriant vegetation.  Water is fairly abundant, though in the dry season obtainable only by digging in the sandy beds of the rivers.  The plateau has an altitude ranging from 4000 to 6000 ft.  It consists of well-watered, wide, rolling plains, and low hills with scanty vegetation.  In the east the tableland falls away to the basins of the Congo and Zambezi, to the south it merges into a barren sandy desert.  A large number of rivers make their way westward to the sea; they rise, mostly, in the mountain belt, and are unimportant, the only two of any size being the Kwanza and the Kunene, separately noticed.  The mountain chains which form the edge of the plateau, or diversify its surface, run generally parallel to the coast, as Tala Mugongo (4400 ft.), Chella and Vissecua (5250 ft. to 6500 ft.).  In the district of Benguella are the highest points of the province, viz.  Loviti (7780 ft.), in 12 deg. 5’ S., and Mt.  Elonga (7550 ft.).  South of the Kwanza is the volcanic mountain Caculo-Cabaza (3300 ft.).  From the tableland the Kwango and many other streams flow north to join the Kasai (one of the largest affluents of the Congo), which in its upper course forms for fully 300 m. the boundary between Angola and the Congo State.  In the south-east part of the province the rivers belong either to the Zambezi system, or, like the Okavango, drain to Lake Ngami.

Geology.—­The rock formations of Angola are met with in three distinct regions:  (1) the littoral zone, (2) the median zone formed by a series of hills more or less parallel with the coast, (3) the central plateau.  The central plateau consists of ancient crystalline rocks with granites overlain by unfossiliferous sandstones and conglomerates considered to be of Palaeozoic age.  The outcrops are largely hidden under laterite.  The median zone is composed largely of crystalline rocks with granites and some Palaeozoic unfossiliferous rocks.  The littoral zone contains the only fossiliferous strata.  These are of Tertiary and Cretaceous ages, the latter rocks resting on a reddish sandstone of older date.  The Cretaceous rocks of the Dombe Grande region (near Benguella) are of Albian age and belong to the Acanthoceras mamillari zone.  The beds containing Schloenbachia inflata are referable to the Gault.  Rocks of Tertiary age are met with at Dombe Grande, Mossamedes and near Loanda.  The sandstones with gypsum, copper and sulphur of Dombe are doubtfully considered to be of Triassic age.  Recent eruptive rocks, mainly basalts, form a line of hills almost bare of vegetation between Benguella and Mossamedes.  Nepheline basalts and liparites occur at Dombe Grande.  The presence of gum copal in considerable quantities in the superficial rocks is characteristic of certain regions.

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