Studies on the Biology of the Grasshopper Pest Zonocerus Variegatus (L.) (Orthoptera: Pyrgomorphidae) in Nigeria: 1911–1981
International Journal of Tropical Insect Science · 1982
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Observations on the biology of three species of Nigerian millipedes
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.
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Floral Biology and Pollination Ecology of Cowpea (Vigna Unguiculata L. Walp)
Studies on the floral biology and pollination ecology of three varieties of cowpea (Vigna unguiculata L. Walp) were carried out. The varieties studied were Var. Oloyin, Var. Sokoto, and Var. Drum. Cowpea is a self pollinated crop which is encouraged by the arrangements of the floral parts. However, Insects visiting cowpea flowers have been implicated in the movement of pollen from one cowpea plant to another. Flower opening of cowpea begins between 6:00am and 6:30am and closes between 11:30am and 12:00pm. Pollen analysis showed similarities in the pollen morphology of the cowpea varieties. Moreover Var. Drum produced the highest number of pollen grains per flower in terms of pollen productivity.