Pilobolus crystallinus var. crystallinus, commonly known as the 'Dung Cannon' or 'Hat Thrower', is a species of fungus belonging to the Mucorales order. It is unique in that it adheres its spores to vegetation, so as to be eaten by grazing animals. It then passes through the animals' digestive systems and grows in their feces. Although these fungi only grow to be 2–4 cm (0.8–1.6 in) tall, they can shoot their sporangium, containing their spores, up to 2 m (6.6 ft) away. Due to an increase of pressure in the vesicle, the sporangium can accelerate 0–45 mph in the first millimeter of its flight, which corresponds to an acceleration of an incredible 20000 g. Using a mucus-like substance found in the vesicle of the fungus, the sporangium can adhere itself onto whatever it lands, thus completing its life cycle. The basionym of this species is Hydrogera crystallina F.H. Wigg. 1780.