In this paper eighty-three species of Chironomidae found along the Great Berg River (Western Cape Province, South Africa) are listed, and their distribution along the river given in tabular form. Fifty-two of these species were bred out in the laboratory from different habitats in the river. The distribution of the larvae is analysed, and the results compared with those obtained from samples collected and analysed by Harrison and Elsworth (1958, Part 1 of this series), and by Harrison (1958, Part 2 of this series), in their work on the same river.