. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON : 245 111. Puccinia silvatica Schrot. JEcidium Taraxaci K. et S. Myk. Heft. i. ;). Puccinia silvatica Schrot. in Cohn, Beitr. iii. 68. Plowr. Ured. p. 172. Sacc. Syll. vii. 627. Sydow, Monogr. i. 656. Fischer, Ured. Schweiz, p. 289, f. 211. Spermogones. In little clusters, yellowish. j^cidiospores. /Ecidia hypophyllous or amphigeiious, on roundish yellow or brown spots, in crowded clusters 2—5 mm. wide, rarely solitary, occa- sionally on the peduncle which they distort, cup-shaped, with tor
. The British rust fungi (Uredinales), their biology and classification. Uredineae. ON : 245 111. Puccinia silvatica Schrot. JEcidium Taraxaci K. et S. Myk. Heft. i. ;). Puccinia silvatica Schrot. in Cohn, Beitr. iii. 68. Plowr. Ured. p. 172. Sacc. Syll. vii. 627. Sydow, Monogr. i. 656. Fischer, Ured. Schweiz, p. 289, f. 211. Spermogones. In little clusters, yellowish. j^cidiospores. /Ecidia hypophyllous or amphigeiious, on roundish yellow or brown spots, in crowded clusters 2—5 mm. wide, rarely solitary, occa- sionally on the peduncle which they distort, cup-shaped, with torn whitish revolute mar- gin ; spores nearly smooth, orange, 14—21 /a. [Uredospores. Sori hypophyllous, scat- tered, minute, oblong, brown ; spores globose to ovate, echinulatc, brown, 20—27 x 15— 22/ji. Teleutospores. Sori hypophj-lhnis, scat- tered, minute, roundish or oblong, reaching 1 mm. in length, pulvinate, black; spores cla- vate, rounded and much thickened (up to 11 /a) above, rarely conically attenuated, gently con- stricted, tapering below, smooth, pale-brown, darker at the apex, 35—55 x 12—18/i,; pedicels brownish, persistent, as much as 40 /* long.] -^cidia on Taraxacuin officinale, June, July. I have seen specimens from both England and Ireland. Teleutospores on species (Fig. 189.) The question whether P. silvatica occurs in Britain is still in the same stats as in Soppitt's time. The wcidium agrees with the one assigned to that species, but the teleutospores have not been found ; there is no evidence that those found on Carex remota at Kew belonged to this species. The distinction of this tecidium from that belonging to P. variabilis lies chiefly in the clustered peridia, which are situated on a thickened part of the leaf, the peridium-cells are arranged in evident rows and the spores form, according to Juel, longer chains. Fischer insists that the peridium cells are thickest on the outer side, while those of P. variabilis are thickest on the inner si
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