 The fungus was first described scientifically as Agaricus <unk> by Italian mycologist Giovanni Antonio <unk> in 1772 , and sanctioned under this name by Elias Magnus Fries in his 1821 Systema <unk> . That same year , Samuel Frederick Gray transferred the species to the genus Mycena . <unk> for the species include Agaricus <unk> named by William Hudson in 1778 , Agaricus <unk> described by August Johann Georg Karl <unk> in 1893 , <unk> <unk> by Franklin Sumner <unk> in 1909 , and <unk> <unk> by William <unk> <unk> in 1916 . 
