Minecraft wiki entry for Mushroom, associated text: Mushrooms found in a swamp biome.
Mushrooms growing in a stronghold cell.
A brown mushroom growing on a tree.
Mushrooms growing in the Nether.
An example of a mushroom fields biome.
A red mushroom growing on a cluster of glowstone in the nether.
The rare occurrence of a mushroom growing on mossy cobblestone in a dungeon.
Mushrooms growing on podzol.
Mushrooms growing on mycelium in a mushroom fields biome.
Brown mushrooms illuminating a red mushroom and surrounding blocks.
Red Mushrooms can spawn naturally on magma blocks in the Nether.
A large amount of mushrooms generated on a beach.