National Museum of Natural Science

The black jelly roll is an inedible gelatinous fungus. It is often mistaken for wood ear fungus, which is edible, leading to poisoning. In Europe, it is called “witch’s butter.” In Taiwan, it is mostly distributed in broad-leaved forests at medium to high elevations. Its fruiting bodies, which look like black brains filled with water, grow on tree branches. After drying, they shrink, resembling a thin piece of black paper. This makes people wonder if this is really a fungus.