. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Ill] PLECTASCALES 75 nuclei have travelled in pairs to the asci, where they unite; but Kuyper, in M. Barkeri, reports fertilization in the female organ. After the fertilization stage the oogonium enlarges and gives rise to asco- genous hyphae while the an- theridium and trichogyne de- generate. Investing filaments grow up to form a sheath, the in ner layers of which consist of delicate, nutritive cells. These degenerate early, producing a mass of protoplasm amongst which the ascogenous hyphae ramify. From the penultimate cells of the latt
. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Ill] PLECTASCALES 75 nuclei have travelled in pairs to the asci, where they unite; but Kuyper, in M. Barkeri, reports fertilization in the female organ. After the fertilization stage the oogonium enlarges and gives rise to asco- genous hyphae while the an- theridium and trichogyne de- generate. Investing filaments grow up to form a sheath, the in ner layers of which consist of delicate, nutritive cells. These degenerate early, producing a mass of protoplasm amongst which the ascogenous hyphae ramify. From the penultimate cells of the latter binucleate asci are developed, and after the nuclei have fused eight spores are formed. The ascus wall breaks down and the spores are finally set free after the decay of the outer layer of the sheath. This sheath, with the en- closed mass of free ascospores, was long regarded as a single organ containing an indefinite number of spores; for this reason the fungus was placed in the Hemiasci and given the generic name of Monascus. The later stages of develop- ment are in fact difficult to follow and have been variously interpreted by different authors. Thus Dangeard describes the oogonium as undergoing septation before it branches, while Barker interprets the mass of protoplasm in which the young asci are found as the remains of the oogonium invaginated by the growth into it of the ascogenous hyphae. Kuyper and Ikeno, on similar grounds, believed the asci to be produced by free cell formation within the oogonium, no ascogenous hyphae being Fig. 35. Monascus furpureus Went.; a. h. stages in the development of the oogonium; after Dangeard. Alonascus X. Schilcorra; c. entrance of male nuclei into trichogyne; d. pairing of nuclei in the oogonium; after Schikorra. ASPERGILLACEAE: BIBLIOGRAPHY 1870 DE Bary, a. Eicrotiu7n, Erysiphe, Cinciiuiobolus nebst Bemerkungen iiber die Geschlechtsorgane der Ascomyceten. Beitr. z. Morph. und Phys. der Pilze, iii, p. i. 1874 Brefeld, O
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
