Many of my students ask me about toxic mushrooms.  Below is a great website to reference if you are curious about mushrooms.  The best rule is to not eat those that are wild-picked, you should only buy mushrooms from approved, reputable suppliers. Many illnesses occur each year when inexperienced mushroom hunters accidentally mistake toxic specimins for edible ones.  All mushroom hunters should be able to identify both edible and toxic mushrooms in their fresh and dried state.