The term mushroom is properly restricted to the plant's above-ground portion, which is the reproductive organ. Although mushrooms contain some protein and minerals, they are largely water and hence of limited nutritive value. Longest living mushroom can live close to fifty years, the Ganoderma applanatum. Biggest mushroom so far discovered is Hericium abietis. The second biggest fruiting body is the giant puffball which can measure up to 2 meters in circumference.
Fungi reproduce through spores, which are the equivelent of a plant's seeds.
There are 38,000 kinds of mushrooms. I've mentioned that psilocin, which is what psilocybin quickly becomes as it enters your metabolism, is 4 hydroxy dimethyltryptamine. It is the only 4-substituted indole in all of organic nature. Let this rattle around in your mind for a moment. It is the only 4-substituted indole known to exist on earth.