 First called Agaricus cinerellus by Finnish mycologist Petter Karsten in 1879 , he transferred it to the genus Mycena that same year . In his 1936 Flora Agaricina Danica ( Agaric flora of Denmark ) Jakob Emanuel Lange referred it to the genus Omphalia ; Omphalia cinerea ( P. Karst . ) J.E. Lange is now a synonym . Mycena cineroides was named and described as a new species distinct from M. cinerella by Hintikka in 1963 , who thought it to be unique due to its narrowly acute cap that lacked brownish or yellowish tones , decurrent gills , and two @-@ spored basidia . However , intermediate forms of it have been found , and some authorities , like Dutch Mycena specialist Maas Geesteranus , believe it should be treated as a synonym of M. cinerella . 
