> The plant I meant is something we call "stenmurkla", botanical name
> Gyromitra esculenta.

i have eaten gyromitra esculenta  many times and never got affected . but it
is true there has been  recorded as producing digestives troubles that occur
with that species and my french mushroom books allways label it as edible
and  warned about being sometimes poisonous ,it must depend it must depend
with the individuals, both in the mushroom and consumers

jean-claude