This is the most peculiar and interesting part of Africa, but owing to the absence of existing barriers its limits cannot be well defined. The typical portion of it hardly contains more than the narrow strip of territory limited by the mountain range which forms the boundary of the Cape Colony and Natal, while in a wider sense it may be extended to include Mozambique. It may perhaps be best characterised as bounded by the Kalahari desert and the Limpopo river. It is in the more limited district of the extreme south, that the wonderful Cape flora alone exists. Here are more genera and species, and more peculiar types of plants congregated together, than in any other part of the globe of equal extent. There are indications of a somewhat similar richness and specialization in the zoology of this country; but animals are so much less closely dependent on soil and climate, that much of the original peculiarity has been obliterated, by long continued interchange of species with so vast an area as that of Africa south of the equator. The extreme peculiarity and isolation of the flora must not, however, be lost sight of, if we would correctly interpret the phenomena afforded by the distribution of animal life on the African continent.
Mammalia.—A much larger number of peculiar forms of mammals are found here than in any of the other sub-regions, although it is far less in extent than either of the three divisions of the continent. Among Insectivora we have the Chrysochloridæ, or golden moles, consisting of two genera confined to South Africa; while the Macroscelididæ, or elephant shrews, are also characteristically South African, although ranging as far as Mozambique and the Zambezi, with one outlying species in North Africa. The Viverridæ are represented by three peculiar genera, Ariela, Cynictis, and Suricata. The Carnivora present some remarkable forms: Proteles, forming a distinct family allied to the hyænas and weasels; and two curious forms of Canidæ—Megalotis (the long-eared fox) and Lycaon (the hyæna-dog), the latter found also in parts of East Africa. Hydrogale is a peculiar form of Mustelidæ; Pelea one of the antelopes; Dendromys, Malacothrix, and Mystromys are peculiar genera of the mouse family (Muridæ); Bathyerges one of the mole-rats (Spalacidæ); Pedetes, the Cape-hare, a remarkable form of jerboa; and Petromys, one of the spiny-rats (Echimyidæ). The remarkable Orycteropus, or earth-pig, has one species in South and one in North East Africa. We have thus eighteen genera of mammalia almost or quite peculiar to South Africa.
Birds.—These do not present so many peculiar forms, yet some are very remarkable. Chætops is an isolated genus of thrushes (Turdidæ). Lioptilus, one of the fruit-thrushes (Pycnonotidæ). Pogonocichla, one of the fly-catchers; Urolestes, a shrike; Promerops, a sun-bird; Philetærus and Chera, weaver-birds; and three peculiar genera of larks—Spizocorys, Heterocorys, and Tephrocorys, complete the list of peculiar types of Passeres. A wood-pecker, Geocolaptes, is nearly allied to a South American genus. The Cape-dove, Œna, is confined to South and East Africa and Madagascar; and Thalassornis is a peculiar form of duck. Several genera are also confined to West and South Africa;—as Phyllastrephus (Pycnonotidæ), Smithornis (Muscicapidæ), Corvinella (Laniidæ); Barbatula and Xylobucco (Megalæmidæ); Ceuthmochares, also in Madagascar, (Cuculidæ); Typanistria (Columbidæ). Other remarkable forms, though widely spread over Africa, appear to have their metropolis here, as Colius and Indicator. Others seem to be confined to South Africa and Abyssinia, as the curious Buphaga (Sturnidæ); and Apaloderma (Trogonidæ). Machærhamphus (Falconidæ) is found only in South-West Africa, Madagascar, and the Malay Peninsula.
Reptiles.—There are 4 peculiar genera of snakes,—Typhline, belonging to the blind burrowing snakes, Typhlopidæ; Lamprophis (Lycodontidæ); Cyrtophis and Pæcilophis (Elapidæ), a family which is chiefly Oriental and Australian. Of Lizards there are 10 peculiar genera; Monotrophis (Lepidosternidæ), but with an allied form in Angola; Cordylus, Pseudocordylus, Platysaurus, Cordylosaurus, Pleurostichus, and Saurophis, all peculiar genera of Zonuridæ; Chamæsaura, forming the peculiar family Chamæsauridæ; Colopus and Rhopitropus (Geckotidæ).
Amphibia.—Of Amphibia there are 4 peculiar genera: Schismaderma (Bufonidæ); Brachymerus (Engystomidæ); Phrynobatrachus and Stenorhynchus (Ranidæ). These last are allied to Oriental genera, and the only other Engystomidæ are Oriental and Neotropical.
Fresh-water Fish.—Of fresh-water fishes there is 1 genus—Abrostomus—belonging to the carp family, peculiar to South Africa.
Insects.—South Africa is excessively rich in insects, and the number of peculiar types surpasses that of any other part of the region. We can only here summarize the results.
Lepidoptera.—Of butterflies there are 7 peculiar genera; 2 belonging to the Satyridæ, 1 to Acræidæ, 3 to Lycænidæ, and 1 to Hesperidæ. Zeritis (Lycænidæ) is also characteristic of this sub-region, although 1 species occurs in West Africa.
Coleoptera.—These are very remarkable. In the family of Cicindelidæ, or tiger-beetles, we have the extraordinary Manticora and Platychile, forming a sub-family, whose nearest allies are in North America; as well as Ophryodera and Dromica, the latter an extensive genus, which ranges as far north as Mozambique and Lake Ngami. Another genus of this family, Jansenia, is common to South Africa and South India.
In the large family of Carabidæ, or ground-beetles, there are 17 peculiar South African genera, the most important being Crepidogaster, Hytrichopus, Arsinoë, and Piezia. Three others—Eunostus, Glyphodactyla, and Megalonychus—are common to South Africa and Madagascar only. There is also a genus in common with Java, and one with Australia.