Clustered oak bonnet mushrooms (Mycena inclinata) growing by a fallen branch. These mushrooms are the inedible fruiting bodies of this fungus and can reach 10 centimetres in height. They have gills on the undersides of the bell-shaped caps from which reproductive spores drift on the wind. There are over 100 types of Mycena mushrooms in Britain. These ones are found on dead oak wood. Photographed in Epping Forest, England.