The cap is often radially wrinkled and varies from grey-brown to a darker brown colour; it is viscid when wet.  The stem has a long base rooting underground in buried wood or tree-roots.  The gills are white and may have a dark edge when mature. The spore print is white. 

The Shield fungi (Pluteus species) can be similar, but have a pinkish spore print. 

Photograph from top down, in side view and from underneath to show gills and full length of stipe.  Note habitat and substrate. 

Woodlands, on roots of trees, especially Beech

Summer and autumn.

Widespread and fairly frequent in Britain.

Status in Leicestershire and Rutland not known.

https://www.first-nature.com/fungi/hymenopellis-radicata.php