Slime mould (Badhamia)

Slime mould (Badhamia)

Observation - Slime mould (Badhamia) - UK and Ireland. Description: This grey stuff was growing over moss on an old log in mature woodland. Is it a fungus or a lichen? An ID? Edit: changed to reflect Nigel's and Alan's comments. Many thanks.

This grey stuff was growing over moss on an old log in mature woodland. Is it a fungus or a lichen? An ID?
Edit: changed to reflect Nigel's and Alan's comments. Many thanks.