AS'CONYCE'TES (Gk. fiakey, askos, skin hag nom. pl. pl./on-cc, ntykeics, mushrooms, fungi). One of the largest groups of Fungi, only rivaled in the number of species by the Basidio mycetes (mushrooms and their allies). its members are readily distinguished by the cha• acteristic fructification called the `ascoearp! The essential elements in an ascocarp are small. delicate sacs, called 'a.sei: Each :Isms gener ally eontains eight spores. called 'aseospores.• There may be only a few asci in au aseoearp, or they may be numbered by the thousand. The asci are usually arranged in a that or concave layer, packed in among parallel sterile hyplee ('paraphyses'), and around the fruiting sur face is a variously modified envelope ('perid imn'). The fruiting surface ( hymen lam) may be entirely inclosed by the peridimn, when the ascocarp is generally a firm, rounded body (eleis tothecium ).
The largest cleistothecia are the truffles, but the condition is also well illustrated by some of the mildews (e.g. the lilac mildew) parasitic on the surface of the leaves of many herbs and shrubs. A very large number of Aseomycetes grow on decaying wood, or as parasites under the bark, and form hard black fructifications, an excellent example of which is the 'black knot' ( Plowrightia ) of plum and cherry-trees. ln most of these forms the ascocarps are cavities termed 'perithecia,' opening to the exterior by a pore, and this type of ascocarp characterizes the group called Pyrenomycetes.
The most beautiful Ascomyeetes, however. have a saueer or cup-shaped ascocarp (apothecium), the upper surface being the hymenium, and fre quently hrilliumtly colored red. yellow. or brown. The most conspicuous of these cup fungi, called Discomyeetes, are in the order Pezizales, and grow in the rich humus of moist woods. They
are fleshy forms, and some species are large enough to be eaten. The saucer-shaped apolhe cium is also very characteristically illustrated in the lichens (q.v.), whose ftmgal portion, with few exceptions, are Ascomycetes.
Some remarkable parasites (e.g. Cordiceps) that attack caterpillars and their pupae are found here. The infected insect becomes mummified by the growth all through its interior of the fungus, which, finally breaking through some region of the body, forms a club-shaped or plum like fructification.
One of the most highly developed of the Asco mycetes, and valued for its gastronomical quali ties, is the 'morel' (ilorchella), a representa tive of a specialized group called the Helvellales, whose members have large, stalked fructifica tions, with an exposed and frequently much con voluted hymenium. They are popularly regarded as mushrooms.
Another interesting Ascomyeete forms the ergot (q.v.) of wheat. This is really a.. resting condition of the body ( sc/crot i ), which gathers in the flower clusters of the wheat and transforms the ovary into a hard, black body. The ergot grain falls to the ground, and under suitable conditions of warmth and moisture be comes soft, putting forth a number of stalks with rounded heads, in which are embedded peri thecia.
In certain cases the ascocarp is known to be the result of a sexual act. (See FUNGI.) For an extensive account of the Ascomycetes consult: Engler and Prantl, Die Nutiirlichen Pflanzenfa, milien (Berlin, 1899—in progress) ; and in Eng lish, Ellis and Everhart, North American Pyre womyeetcs (Newfield, N. J., 1892) ; and Phil lips, British Discomyeetes ( London, 1888).