. The British rust fungi (Uredinales) their biology and classification. Rust fungi. Fig. 252. E. Sem- pervivi. Sori on Seinpervivum mon- tanum (reduced). Speriiwgones. Scattered amongst the seciSia, roundish. Teleutospores. Sori rather large, amphi- genous, sunken in the leaf, secidium-like, sur- rounded by many layers of hyphse and by a peridium, which opens by a pore at the summit and finally becomes cup-shaped; spores bluntly polygonal or roundish, yellowish-brown, densely reticulate-ver rucose, 24—35 x 21—28/x; epispore 3—4i/jl thick. On Sempervivum tectorum; also found on *S. calcareum, S
. The British rust fungi (Uredinales) their biology and classification. Rust fungi. Fig. 252. E. Sem- pervivi. Sori on Seinpervivum mon- tanum (reduced). Speriiwgones. Scattered amongst the seciSia, roundish. Teleutospores. Sori rather large, amphi- genous, sunken in the leaf, secidium-like, sur- rounded by many layers of hyphse and by a peridium, which opens by a pore at the summit and finally becomes cup-shaped; spores bluntly polygonal or roundish, yellowish-brown, densely reticulate-ver rucose, 24—35 x 21—28/x; epispore 3—4i/jl thick. On Sempervivum tectorum; also found on *S. calcareum, S. globiferum, S. montanum (Plowright), S. arachnoideiim (Fischer) and others (Saccardo). Not common, Warwick- shire, Forden, Kew Gardens, etc. April— August. (Figs. 252, 253.) It lias been proved by De Bary, Hoffrnann and others that the basidiospores produced by the teleutospores infect the leaves, and from them arises a mycelium which perennates in the stem. It produces spermogones and teleutospores in the following spring.^ The affected leaves are more erect than normal ones, twice as long, narrower and yellowish at the base: infested plants should be burnt, so that they may not infect others. See the fuller account given on pp. 53-5. Distribution: Fig. 253. E. Semper- vivi. jBeidio-teleu- tospore germinating (after Hoffmann).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Grove, W. B. (William Bywater), 1848-1938. Cambridge, University Press
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishercambr, bookyear1913
