Phylum: Basidiomycota Family: Russulaceae
Russula fellea (Fr.) Fr.
Geranium Brittlegill
Common under Beech. The yellow cap can be quite ochreous in the centre and almost white at the edges. Sticky when wet. It's described as having a faint smell of Pelargonium, hence the common name
References:
Kibby (2009) The Genus Russula in Great Britain
Breitenbach & Kranzlin (2005) Fungi of Switzerland, Volume 6, Russulaceae
Monedero García (2011) El Genero Russula en la Peninsula Iberica