Darlington visited Johannesburg and Pretoria and made tours to 'S.W. Africa, Transkei and Northern Transvaal [Bantu] Homelands'. He lectured in Pretoria on genetics and the origin of society, 22 Jul 1963. He broke his return journey to spend a few days in Kenya. He accumulated much material which he later used for his book The Evolution of Man and Society.

Material comprises correspondence arising from visit to Africa. Includes exchange with editor of The Humanist re exhibits on evolution in the Transvaal Museum to which the South African Minister of Education had taken exception.