S. Afolabi Toye

An account is given of the occurrence of Pandinus imperator imperator (C. L. Koch) and Buthus hottentotta hottentotta Fabricius which are two common species of scorpions in Nigeria. P. imperator is essentially a forest species commonly found in the lowland rain forest zone, while B. hottentotta typically lives in the savannah and has a much wider distribution stretching from the derived savannah to the Sudan zone. During aktograph experiments, P. imperator showed greater locomotory activity during the daytime than at night. In contrast, B. hottentotta was markedly nocturnal. The normal rhythm of locomotory activity of B. hottentotta was greatly affected by constant artificial illumination (20 foot candles) and constant darkness. The rate of water‐loss of P. imperator in dry air was greater than that of B. hottentotta. The experimental results are discussed in relation to the behaviour of the scorpions in their natural habitats.

Investigations have been carried out, both in the field and in the laboratory, into certain aspects of the biology of three species of millipede ( Spirostreptus assiniensis, Oxydesmus sp., and Habrodesmus falx ) which commonly occur during the rainy season in the Ibadan area of Western Nigeria. The feeding, mating, egg‐laying, and moulting habits of the three species are described. A detailed description is given of the nest‐building habit of the larvae of Oxydesmus sp. The elaborate nests which are built primarily for moulting also protect the larvae during the dry season when moisture conditions become unfavourable. Swarming behaviour, uncommon in millipedes, is shown by the larvae of H. falx . This behaviour which appears to be of survival value to the species is described.