Fungi, Ascomycetes, Ustilaginales, Uredinales . n the young mycelium, did not persist. It is no doubtdependent upon rapidity of growth. From this mycelium pairs of uninucleate branches grow up, usually fromthe same, sometimes from different hyphae, and fuse at their apices (fig. 19).Their nuclei also fuse and after three karyokinetic divisions eight spores areformed. Sometimes, especially in old cultures, the fertile hyphae mayproduce asci without fusion. These are usually small and generally containfour spores or even a lesser number. As a rule three nuclear divisions takeplace in the parthen
Fungi, Ascomycetes, Ustilaginales, Uredinales . n the young mycelium, did not persist. It is no doubtdependent upon rapidity of growth. From this mycelium pairs of uninucleate branches grow up, usually fromthe same, sometimes from different hyphae, and fuse at their apices (fig. 19).Their nuclei also fuse and after three karyokinetic divisions eight spores areformed. Sometimes, especially in old cultures, the fertile hyphae mayproduce asci without fusion. These are usually small and generally containfour spores or even a lesser number. As a rule three nuclear divisions takeplace in the parthenogenetic asci, and eight nuclei are formed, though theydo not all function. According to Guilliermond it would seem that thenumber of spores is conditioned not by any cytological peculiarity, butrather by the supply of nutritive material. The species of the genus Endomyces possess a branched, septate myce-lium. It may break up into oidia, which sometimes become surrounded bythick walls and form cysts, or it may produce yeast-like conidia which. Fig. 18. Eremasais albus Eidam; a. b. c. d. sexualapparatus; e. /. %. h. fusion of gametangia; *. /!;. development of asci; /. parthenogenetic ascus;x 900-1000; aft ?• Eidam. Ill PLECTASCALES 59
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
