. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] SPHAERIALES 157 long hairs around the ostiole, and from the Sphaeriaceae in the habitat and type of spore. The mycehum is in most cases composed of multinucleate cells, but in Podospora hirsuta the cells are uninucleate (fig. 115), recalling the condition in several species of Chaetomium. The commonest type of archicarp is a stout, coiled, septate hypha which soon becomes surrounded by vegetative filaments; it is usually terminal, but is occasionally intercalary, for instance in Sordaria fimicola. Dangeard has found a straight archicar
. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. V] SPHAERIALES 157 long hairs around the ostiole, and from the Sphaeriaceae in the habitat and type of spore. The mycehum is in most cases composed of multinucleate cells, but in Podospora hirsuta the cells are uninucleate (fig. 115), recalling the condition in several species of Chaetomium. The commonest type of archicarp is a stout, coiled, septate hypha which soon becomes surrounded by vegetative filaments; it is usually terminal, but is occasionally intercalary, for instance in Sordaria fimicola. Dangeard has found a straight archicarp (fig. 116) in Sordaria macrospora, and in 1868, for .S. fimiseda, Woronin described an archicarp with a swollen terminal cell recalling the oogonium of Hwnaria Fig. 115. Podospora hirsuta Dang., archicarp; alter Dan- geard. Fig. 116. Sordaria macrospora Kvit^x's^r^ a. straight archicarp ; after Dangeard. In Sporormia intermedia the peritheclum is initiated,by the enlargement of a multinucleate mycelial cell which is often intercalary. It undergoes not only transverse but also longitudinal divisions, forming a pseudoparen- chymatous massof uninucleate cells(fig. 117), with which various neighbouring cells anastomose. The mass thus formed is responsible for the whole contents of the perithecium, though the outer walls may be formed by ordinary vegetative hyphae. In view of this fact it seems doubtful whether the initial cell should here be regarded as an ., oogonium, that is to say as having at \\_ one time had a sexual significance, and not rather as a preliminary stage in the development of such a mass of hyphae as initiates the apogamous perithecium of Claviceps and its allies. In some of the Sordariaceae each Fig. 117. Sporormia inlermedia \\iex%viâ ; \x\\\SsX spore is surrounded by a layer of cells of perithecium; after Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colorat
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
