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The article discusses a research paper on the vegetation of Natal, with special reference to the Pietermaritzburg district in South Africa. It considers the influence of topography and physiography and the concepts of stable and unstable habitats together with growth forms in considering the factors influencing the plant formations. The article also describes the seven plant formations of natural vegetation under which the vegetation of the district was divided. A number of plates and a vegetation map illustrates the research paper.

The article presents some facts on the ecology of Bifurcaria brassicaeformis, the only species of the Fucalis genus in South Africa, which forms extensive intertidal communities. B. brassicaeformis is an endemic species with a limited distribution range. It then briefly considers the complex current system off South African coasts and stresses that B. brassicaeformis is most typical of temperatures intermediate between those of the cold waters off the west coast and of the warm waters east of Cape Agulhas. In addition, the plant also occurs as a common rock-pool species especially in the lower half of the intertidal region. Other significant information related to the matter is also provided.

The article discusses the occurrence of Salix humboldtiana in temperate South America at or near the latitude of Buenos Aires. It is cited that Lucien Hauman refers to the occurrence of the genus as a riparian shrub in the Monte, where the vegetation is xerophilous. It is mentioned that the occurence of this willow is as far south as the lower reaches of the River Chubut. It is said that the river is approximately 44 degrees of south latitude, 9 degrees farther south than Cape Agulhas in South Africa.

The article focuses on a study which investigates some aspects of the interaction of plants, rabbits and seabirds on nine islands in South Africa. One of the most important results of the study is the intense competition between plants and animals for the space available on the islands, particularly on breeding areas. Rabbits, which are very rare on the African mainland because of the abundance of predators, exert a profound influence on the island vegetation, while bush-nesting birds are linked with the start and end of the rabbit plagiosphere, but are excluded from the middle phases which are occupied by ground-nesting birds. Moreover, branch conformation of shrubs has an important bearing on selection of nest site by cormorants.

The article presents a study of mangrove swamps in Natal and Pondoland, South Africa. It shows that the southernmost of the mangrove swamps are more typically zoned than the northern and that the atypical zonation is due to the presence of sand which appears to restrict the growth of certain species, such as Bruguiera, Rhizophoram and Ceriops. It suggests that where mangroves develop into a typical mangrove swamp, they are accompanied by the same assemblage of animals, where in the animals, with a few exceptions, do not extend to the south of the southernmost mangrove swamps. It concludes that the mangrove fauna is in fact a fauna of very sheltered marine shores and not an estuarine one, not a fauna characteristic of regions with a salinity gradient, but of regions with avariable salinity.

The article presents a study on the ecology of a South African fen, Groenvlei. It relates that Groenvlei is a shallow coastal lake between Wilderness and Goukamma River on the south coast of South Africa where rainfall is evenly distributed and it is also described as calcareous due to the presence of sand dunes as well as eutrophic by nature. The study describes the trends in plant succession which include the primary succession leading to fen carr as well as the secondary succession due to human utilization of the fen. The study also identifies a slight tendency to isotropic conditions and the vegetation of sand intrusions, sandy fen margin and dunes surrounding the lake.

The article presents a study that examines the ecology of the intertidal plant and animal communities in Zwartkops Estuary in South Africa. These communities include the fauna of solid substrata and the fauna of sand and mud banks that is composed of the epifauna and the infauna. A discussion about the nutritional relationships of species, the biotic factors influencing animal and plant distribution, the commensalism relationship of some species, and the zonation of animals on mud flats and sand banks in the estuary is also provided.

The article presents an ecological survey of plants and animals in the intertidal regions of the Zwartkops estuary near Port Elizabeth in South Africa. The Zwartkops river enters Algoa Bay some 10 kilometers north-east of Port Elizabeth. The estuary's associated water forms include large sand banks and mud flats, which has near proximity to industrial areas of Port Elizabeth. The article is divided into four parts: introduction, topography and description of the estuary, the physical and chemical features, and the zonation of plants. Discussions under the physical and chemical features include climate, salinity, temperature, substratum, turbidity and pollution. The zonation of plants is divided into three: upper and middle reaches, lowere reaches, and higher zones.

The article presents a preliminary account of the aquatic and sub-aquatic vegetation and flora of the Witwatersrand. The area investigated extends from Florida, nine miles west of Johannesburg, to Brakpan, twenty-three miles east of the city. The sheets of water are classified into different kinds. Artificial dams are usually in connection with gold mines and of little botanical interest. Semi-natural lakes are made by the artificial damming up of natural streams. Finally, natural sheets of water which are pans or shallow depressions whose origin is in dispute and streams and their backwaters.

The author suggests several locations in South, Central and East Africa that he considers desirable for ecological surveys. The territories suggested for consideration include the Union of South Africa, Swaziland, Basutoland, Bechuanaland, Southern and Northern Rhodesia, Nyassaland, Uganda, Tanganyika and Kenya. The objectives of the ecological surveys are outlined, including gaining information as to the nature, development and ecological interrelations of the more important biotic formations and the succession stages leading to these. The suggested procedure for the ecological survey is described.

The article presents an analysis of the features of plant communities on Table Mountain in South Africa. The analysis has found that the plant communities have large and varied population, and that individual plant species are in most cases not evenly distributed through the area of the community. Using the sample quadrat method, the authors were able to classify the species in accordance with Raunkiaer's life-form and leaf-size classes. It relates the findings of the examination of stages in succession.

The article presents a study that examined the factors that contributes to the vast vegetative succession in South Africa. It discuses the factors as well as determines the role of climate difference on the region's vegetation and notes climatic factors as the basis of the classifications. It also enumerates the three cycle of vegetative successions, which include regional succession, topographic succession and biotic succession and details on the plant's succession on bare rock-surfaces and clefs in the South African land.

The article reviews the periodicals "Biological Conservation" and "Koedoe. Journal for Scientific Research in the National Parks of the Republic of South Africa."