The germination response of Uraria picta to five environmental factors was investigated. It germinated both in light and dark but germination in the light was significantly better than in the dark; there was further germination when seeds first placed in the dark were later brought into the light. It germinated well in the three soil types used but germination in humus and sand was significantly better than in red earth. There was an increase in germination with an increase in burial up to 1.5 cm, thereafter germination levelled off. There was no germination in water-logged conditions and there was an increase in germination as soil moisture decreased. Alternating temperatures of 31/21°C and 31/15°C favoured germination while 21/15°C inhibited germination. The results are discussed in relation to the phenology and distribution of the species.

A possible relationship between the moss, Hyophila crenulata and the Nigerian garden snail, Limicolaria aurora was investigated. Freshly ground moss paste, unground moss, waterleaf (Talinum triangulare) paste, a mixture of ground moss and cassava starch paste (1 : 1) and cassava starch paste alone were fed to different groups of snails for 10 days. A field experiment in which some snails were restricted to the moss population on a drainage wall for 10 days was also carried out. There was a significant difference in the live weight of the different groups of snails (P,0.05) in the laboratory experiment. The group fed with moss paste had a significantly higher live weight than any of the other groups. The group fed with unground moss and those in the field experiment actually lost weight indicating an inability to feed on and digest the whole moss. The results indicate that the snails use the moss, which is always moist and cool, only as habitat and not as food. Thus the nutrients trapped within the cells of mosses may only enter the nutrient cycle of the ecosystem when the moss dies and decomposes or by mechanical crushing.

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Uraria picta leaf-pair unrolling inside out is a remarkable feat. A leaf-pair was investigated to understand the mechanism of spontaneous reverse inside out act of the plant. The upper (adaxial) and lower (abaxial) surfaces of the leaf-pair were examined using scanning and light microscopy. The scan showed diversity of hairs varying in shape from straight, pointed, curve, and club to hook. There were deposits of wax on both sides of the leaf-pair. The light microscope showed hairs are restricted to the midrib on the adaxial surface of the leaflets. Hooked hairs dominated the entire abaxial surface of the leaflets. The transverse section of the midrib section showed abundance of structural and mechanical tissues, collenchyma and sclerenchyma tissues. Both morphological and anatomical attributes were used to explain the mechanism and how the plant got its Yoruba vernacular name 'Alupayida' as well as its purported use in changing the sex of the unborn child and in breaking up love affairs.

The Lagos-Ibadan Expressway is the busiest inter-state route in Nigeria and one of the largest road networks in Africa. It handles more than 250,000 PCUs (Passenger Car Units) daily. Amount of metal emissions being released daily from vehicles plying this road into the environment (air, soil, plant and water) is great! This study evaluated heavy metal composition in soils resulting from exhausts pollution from vehicular movement along Lagos-Ibadan Expressway. A total of two hundred and seventysix soil samples were collected at 5, 15 and 25 m away from the edge of the road. The soil samples were collected with hand auger from the surface to a depth of 10 cm during both dry and wet seasons. Heavy metal concentrations were determined using Atomic Absorption Spectrophotometer (AAS). The heavy metal concentrations found in sampled soil during dry season in mg.kg -1 along the study sites revealed the following,