Smut

Smut (Ustilago Carbo), a phycomycetous fungus, parasitic upon grasses, especially oats and other cereals. Its mycelium permeates the seeds and other reproductive organs of the host, forming black spores, which germinate when the seed falls, producing a pro-mycelium with sporidia. These latter, in turn, produce a new mycelium, which penetrates young plants. The allied fungus Tilletia Caries produces the similar disease in wheat known as bunt.