Stinkhorn fungus (Phallus impudicus) with flies eating the black sticky spores on its spore-cap (upper left). Stinkhorns develop from an egg-like object which is connected to the rest of the fungus by white strands. As the hollow stalk (white) grows, it ruptures the gelatinous outer layer and raises a bell-shaped head up to 25 centimetres above the ground. The head is covered in a foul-smelling slime which gives this mushroom its name. Flies are attracted to the slime and they disperse the spores it contains.