Fungi, Ascomycetes, Ustilaginales, Uredinales . as a local stimulant causing more or less markedhypertrophy and consequent curling or malformation of the infected may be stored by the host, and this is so abundant in the hyper-trophies caused by the aecidial mycelium of Puccinia Caricis on the nettle,Urtica parvifolia, that they are eaten by the Himalayans; one or two otherspecies are similarly employed. Where the mycelium penetrates into theperennial tissues of the host it is itself perennial. Spores and Sori. On the mycelium several kinds of spore are produced,minute spermatia in
Fungi, Ascomycetes, Ustilaginales, Uredinales . as a local stimulant causing more or less markedhypertrophy and consequent curling or malformation of the infected may be stored by the host, and this is so abundant in the hyper-trophies caused by the aecidial mycelium of Puccinia Caricis on the nettle,Urtica parvifolia, that they are eaten by the Himalayans; one or two otherspecies are similarly employed. Where the mycelium penetrates into theperennial tissues of the host it is itself perennial. Spores and Sori. On the mycelium several kinds of spore are produced,minute spermatia in spermogonia, aecidiospores in aecidia, uredospores andteleutospores, sometimes mixed, sometimes separate, in more or less definitesori. One or more of these types of spore may be lacking, but the teleuto-spores are almost invariably present, and it is on them that the classificationof the group depends. Naturally enough it was some time before the various types of sporewere recognized as belonging to the same fungus and the old generic names. Fig. 164. Germinating teleutospores ; a. Phragmidium bulbosum Schm.; b. Triphragmidium UlmariaeLk.; c. Colcosporitim Sonchi Lev.; d. Uromy es appendiculatus (Fabae) Lev.; after Tulasne. (II. VIII] IRKIMXALKS ?97 of the spore forms other than tlie teleutospore, such as Aecidium, Caeomaand Uredo, still survive in our nomenclature. The teleutospores (figs. 164, 165, 166) may be unicellular or they maybe made up of two or more cells forming a compound structure, each cell of
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
