A pale cup fungus, initially cup-shaped but expanding and becoming irregular in shape as it matures.  Margin serrate. 

Other cup fungi may be found on dead wood - e.g. Peziza,Tarzetta and related species. 

microscope

We recommend that this is verified by an expert from a specimen before submission to NatureSpot.  Microscopic examination will be needed.  Also photograph in habitat, and note habitat and substrate.

Woody debris, including woodchip and sawdust