This genus includes an uncertain number of species and is of worldwide distribution. Its very delicate and wonderfully constructed fruit bodies are commonly found growing in groups on rotting wood, on dung, on old saw-dust and on rotten twigs and leaves. The immature fruit bodies are pale yellowish or whitish, spherical, and are immersed in white cottony mycelium. At maturity, the outer wall splits from the top into four to eight sharp pointed teeth, which bend outwards exposing the single, spherical, orange-yellow, spore-containing ball. Six layers can be distinguished in the young peridium but at maturity only two remain distinct, separated by an air space and joined at the extremities of the points — as if it were one cup within another, the inner cup containing the glebal ball (peridiole), immersed in a slimy liquid. The glebal ball is about 1.4 mm in diameter, covered by a thin, adhesive brown skin, and consists of tens of thousands of thick-walled spores and thousands of gemmae embedded in the tough matrix. The spores are at first borne on basidia but at maturity the basidia disintegrate and the centre is filled with a mass of spores. The gemmae are larger, oval or oval-elongate, pieces of vegetative hyphae and gemmae are capable of germination. Suddenly, due to tissue tension, the inner cup turns inside-out and the peridiole is catapulted with such force that it may travel vertically a distance of several metres. The outer, non-everting, membrane holds fast the inner membrane by its teeth and prevents it from ejecting after the peridiole.