Tilletia
(named in honour of Matthieu Tillet, a French botanist of the eighteenth century). A genus of Fungi, parasitic on grasses. The most conspicuous species (T. Caries=T. Tritici) is found in the ovaries or immature fruits of the various kinds of Wheat, which it fills with a mass of dark brown spores. Externally, the grains look quite healthy, or may be distinguished from the ripe fruits only by their dull green colour; but their whole interior is occupied by the spores of the Fungus, and, on being crushed, they are found to be greasy to the touch, and to emit a disagreeable smell. Under the microscope, the spores are seen to be globular, with a network of ridges over the surface. The diseased condition of the Wheat is known to farmers by the names "Bunt," "Stinking Rust," "Stinking Smut," or "Pepper-brand." On germinating, each spore emits a thread of mycelium, which bears on its tip a circle of slender conidia, united in pairs by cross-branches. The conidia fall,-and produce mycelium, on which grow other conidia, from which mycelium is emitted; and on this the spores are formed. Several other species of Tilletia grow in the ovaries of grasses, e.g., T. Lolii in Lolium remotum, T. Secalis in Rye (Secale cereale), &c.; while others form dark brown streaks in the leaves of several grasses; T. striaeformis is the commonest of the latter species. It has been asserted, but not confirmed, that the use of bunted meal causes disease.