- A diseased condition of rye and other cereals, in which the
grains become black, and often spur-shaped. It is caused by a parasitic
fungus, Claviceps purpurea. - The mycelium or spawn of this fungus infecting grains of rye
and wheat. It is a powerful remedial agent, and also a dangerous
poison, and is used as a means of hastening childbirth, and to arrest
bleeding. - A stub, like soft horn, about the size of a chestnut,
situated behind and below the pastern joint. - See 2d Calcar, 3 (b).