Introduction to the study of fungi : their organography, classification, and distribution for the use of collectors . secondary promycelial spores, SMUT FUNGI—USTILAGINES 255 and these again may continue to multiply themselves manytimes by budding, after the manner of yeast-spores, which isthe term applied to them by Brefeld, but liable to misinter-pretation. In order the better to comprehend the process, itmay be detailed as observed in Tilletia (Fig. 120). This parasiteproduces its teleutospores within the grains of wheat, and isknown to farmers as appearance of the grainsexternally
Introduction to the study of fungi : their organography, classification, and distribution for the use of collectors . secondary promycelial spores, SMUT FUNGI—USTILAGINES 255 and these again may continue to multiply themselves manytimes by budding, after the manner of yeast-spores, which isthe term applied to them by Brefeld, but liable to misinter-pretation. In order the better to comprehend the process, itmay be detailed as observed in Tilletia (Fig. 120). This parasiteproduces its teleutospores within the grains of wheat, and isknown to farmers as appearance of the grainsexternally is very littlechanged, but slightly darkenedin colour, and when crushedare seen to be filled witha sooty, rather fetid teleutospores are globose,dark coloured, almost black,and the surface minutelyreticulated. When placed inwater they germinate in aboutforty-eight hours. A germ-tube is emitted from a verysmall germ-pore, but it doesnot attain any considerablelength; and this germ-tubeconstitutes the promyceliima,into which the contents of theparent spore pass and retreatto the extremity, and are. Fig. 120.—Tilletia spores in germination.(, producing a promycelium, ^j ; b,primary spore with iiromycelium, ^j,bearing conidia, of which some areconjugating ; c, conjugated gonidia ingermination, with secondary gonidiuniat s. After De Bar v. shut off by the formationof a transverse septiuu. Tuberculations are soon manifestabout the summit, and these by lengthening become thefirst promycelial spores. They are thread - like, curved,and colom-less, to the number of from four to a fully developed they are cut off from the pro-mycelium by a septum at the base. Soon afterwards theseprimary spores will be seen to connect themselves, mostly inpairs, by a transverse connective, performing an act of conjuga-tion. These conjugated primary spores are often separatedfrom the promycelium, but they may remain for a long timeattached. In due time budding takes place, and
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Keywords: ., bookauthorcookemcm, bookcentury1800, bookdecade1890, bookyear1895
