Cup Fungus

A pale cup fungus, probably a Peziza sp, growing on a beech log (Fagus sp).  It was about 5cm across.

I took the following specimen home with me:

This yielded the following spores (magnification x600, field width 86um):

These are about 15 x 7.5um.

First photo and specimen taken in the Wilderness, Whiteknights Park, Reading, UK, on 2014-01-11.

Update on Fri 2014-02-07 by Tristram Brelstaff

Probably Peziza repanda.