Kingdom:Fungi
Division:Basidiomycota
Class:Agaricomycetes
Order:Agaricales
Family:Tricholomataceae
Genus:Mycena

This mushroom grows in small clumps on wood in damp conditions and can grow to a height of 30 mm with the cap up to 15 mm across. The stem can be 10 - 50mm high, 1 - 3 mm across.  It appears during  Autumn

Jelly stemmed helmet mushrooms. These were very small 3 to 5 mm across the cap.[1]

The top surface of the cap

The underside showing the pores of the gills
[2]

The underside of a 3mm wide stem with an insect feeding inside.

 

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