Oudemansiella mucida

The German name for this fascinating specimen and example of mushroomkind is the rather unattractive Beringter Schleimrübling, (‘ringed slimerooting’ [ouch! :-)]) while in English it is called, somewhat more poetically, a Porcelain mushroom. It is also apparently digestible (in the sense of ‘won’t make you sick’) once washed thoroughly, but not yum.