Diseases of plants induced by Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae diseasesofplants00tube Year: 1897 SPHACELOTHECA, 303 this fungus us follows:' ' Sphacelotheca forms its compound sporophore in the ovule of its host. When the ovule is normally and fully developed in the young flower, the parasite, which always grows through the flower-stalk into the place of insertion of the ovary, sends its hyphae from the funiculus into the ovule, where they rise higher and higlier and surround and penetrate its t


Diseases of plants induced by Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae diseasesofplants00tube Year: 1897 SPHACELOTHECA, 303 this fungus us follows:' ' Sphacelotheca forms its compound sporophore in the ovule of its host. When the ovule is normally and fully developed in the young flower, the parasite, which always grows through the flower-stalk into the place of insertion of the ovary, sends its hyphae from the funiculus into the ovule, where they rise higher and higlier and surround and penetrate its tissue to such an extent as almost entirely supplant it, and thus an ovoid fungus-body of densely interwoven hyphae takes tlie place of the ovule. The micropylar end of the integu- ments alone escapes the change, and remains as a conical tip (Fig. 164 6*) on the apex of the fungus-body and gradually turns brown and dries up. The fungus- body is at first colourless and uniforndy composed of much- branched hyphae, which are woven together into a compact mass and have the gelatinous walls of the simple sporophore of Ustilago to be described below. If it has retained its ovoid form as it steadily increased in volume, differentiation begins first in the apical region into a comparatively thick outer wall which is closed all round, an axile columnar cylindrical or club-shaped body, the columella, both parts remaining colourless, and a dense spore-mass which fills the space between the two and becomes of a dark violet colour (Fig. 164 C, D). The lower part which corresponds to the funiculus and chalaza of the ovule remains undifferentiated, and an abundant formation of new hyphae is constantly taking place in it. This new formation is so added from below to the differentiated portion, that the latter constantly increases ' De Bary, Morphology and Biology of the. Fungi, English Edition, p. Fig. 104.—Siikacelotheca hydropiperis in the flower of Polygonxun Hydroinper. A, Ripe c


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