. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 168 PUCCINIA the fusiform shape, thin walls, and pale colour of the teleutospores, which often become totally devoid of thickening at the apex, by the dropping off of the pale thickening cap, on germination. P. punctata is additionally distinguished by the presence of the seoidium. Fischer explains the fact, that distortions more usually accompany P. Valantiae, by the consideration that infection takes place from the basidiospores mainly through the cuticle of young and still growing parts, while teleuto-sori o
. The British rust fungi (Uredinales) their biology and classification. Rust fungi. 168 PUCCINIA the fusiform shape, thin walls, and pale colour of the teleutospores, which often become totally devoid of thickening at the apex, by the dropping off of the pale thickening cap, on germination. P. punctata is additionally distinguished by the presence of the seoidium. Fischer explains the fact, that distortions more usually accompany P. Valantiae, by the consideration that infection takes place from the basidiospores mainly through the cuticle of young and still growing parts, while teleuto-sori of P. punctata and P. Celakovskyana are produced by infection from spores whose germ-tubes can penetrate the stomata of parts of the plant which are already fully developed. The relations between the three species are very like those which subsist between Uromyces TrifoUi-repentis, U. Trifolii, and V. Jteotens. Distribution : Europe, North America. 40. Puccinia difibrmis K. et S. Puccinia difformis K. et S. Myk. Heft. i. 71 (1817). Cooke, Handb. p. 501 ; Micr. Fung. p. 208. P. Oalii Plowr. Ured. p. 144 P. ambigua Lagh. in Sydow, Uredineen, no. 1056 (1897). Sacc. Syll. xvi. 288. Sydow, Monogr. i. 216. ^ddiospores. ^cidia hypophyllous, on yellow spots, soli- tary or irregularly disposed over the whole leaf, whitish-yellow, with torn reflexed margin; spores verruculose, orange, 13—25 fi. Teleutospores. Sori hypophyllous or on the stems, small, elliptic, soli- tary or clustered, on the stems often elongated and confluent, long covered by the ash-coloured epidermis, then naked, firm, black; spores ellipsoid to clavate, much thickened above, hardly constricted, tapering below, smooth, brown above, paler downwards, 35— 55 X 15—25 fi; pedicels brownish, persistent, as long as the spore or 118. p. difformis. Teleutospores. On Oalium Aparine. 118.) July—August. Surrey, Kent. ( Please note that these images are extracted from scanned page images that may ha
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