A parasitic mould that grow on fungi in the genus Mycena or Collybia.  The caps of the host fungus are invaded by the Spinellus mycelium, eventually breaking through with a fuzzy mass of 'pins'.  These are made up of sporangiophores (the stalks)  each terminating in a minute spherical sporangia, which contain the spores. 

Two other species of Spinellus are on the UK checklist of fungi

For certainty, the specimen should be examined with a microscope or confirmed by an expert. Photograph the mould on the host fungus, and identify host if possible.  

Mycena (Bonnets) or Collybia

Autumn.

https://www.first-nature.com/fungi/spinellus-fusiger.php