Light micrograph of fruiting bodies from the slime mould Physarum citrinum. Within the fruiting bodies are spores that will germinate into free-living, single-celled amoeba. The amoeba aggregate to form a plasmodium, a large single cell with multiple nuclei. The plasmodium can move slowly, feeding on bacteria, fungi and decaying matter. In poor conditions the plasmodium forms fruiting bodies and the life cycle begins again. Slime moulds were once classified as fungi but are now classified as protozoa. Magnification: x30 when printed at 15cm wide.