. The British rust fungi (Uredinales), their biology and classification. Uredineae. 110 UKOMYCES clusters, cup-shaped, whitish-yellow, with a torn revolute margin; spores densely and minutely verruculose, yellowish; 15—21 fj. Fig. 62. IL Behetiis. a, secidia on early leaf, b, fecidia on later leaf, of <S'. infiata ; two telentospores. Teleutospores. Sori bypophyllous and on the stems, often surrounding the secondary secidia, irregularly scattered, gre- garious or circinate, rounded or oblong, covered for a considerable time by the lead-coloured epidermis, rather small and compact, br
. The British rust fungi (Uredinales), their biology and classification. Uredineae. 110 UKOMYCES clusters, cup-shaped, whitish-yellow, with a torn revolute margin; spores densely and minutely verruculose, yellowish; 15—21 fj. Fig. 62. IL Behetiis. a, secidia on early leaf, b, fecidia on later leaf, of <S'. infiata ; two telentospores. Teleutospores. Sori bypophyllous and on the stems, often surrounding the secondary secidia, irregularly scattered, gre- garious or circinate, rounded or oblong, covered for a considerable time by the lead-coloured epidermis, rather small and compact, brownish-black or black; spores subglobose or obovate, rounded above and thickened (as much as 11 /u), smooth, pale brown, 25—35 X 20—27 /x ; pedicels persistent, faintly yellow, thick, as much as 75 fi long. On Silene injlata (latifolia), S. maritima. Not common, ^cidia and teleutospores, July—October. (Fig. 62.) The spots occupied by the secidia vary in colour, but the primary ones are often tinged or margined with purple. This is one of the species whose eecidiospores are capable of reproducing the secidia, as Dietel has shown (Flora, Ixxxi. 395, 1895). The primary a3cidia, on the earlier leaves, are in roundish groups or concentric circles, only a few being scattered. The secondary tecidia, on the younger leaves, stand more often singly and are spread over a larger area ; the teleuto-sori spring from the same secondar}' mycelium or are formed separately. The secondary ajcidia are not confined to the beginning of the season, but continue to be produced till the end of autumn, being in fact the repi'esentatives of the uredo-sori. On this account this species is very interesting biologically. The primary secidia arise from infection by comparativel}^ few basidiospores ; the secondary arise from the moi'e widely dispersed secidiospores of the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - color
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishercambr, bookyear1913
