Mycelium arachnoid; appendages floccose, simple or irregularly branched.—Berk. Outl., p. 404.
* Sporangia 2-spored.
Erysiphe Linkii, Lév. Mugwort Blight; amphigenous; mycelium web-like; fugacious or persistent; conceptacles minute, globose, scattered, emersed; appendages white, interwoven with the mycelium; sporangia 8-20, pyriform, with elongated pedicels.—On leaves of Mugwort. Autumn. Frequent. ([Plate XII.] figs. 248, 249.)
Erysiphe lamprocarpa, Lév. Composite Blight; amphigenous; mycelium web-like, fugacious or persistent; conceptacles minute, globose, scattered, or gregarious; appendages coloured, interwoven with the mycelium; sporangia 8-16, shortly pedicellate.—On leaves of Salsify, Scorzonera, Plantain, &c. Autumn. Not uncommon. ([Plate XII.] figs. 250, 251.)
** Sporangia 3-8-spored.
Erysiphe graminis, D.C. Grass Blight; amphigenous or epiphyllous; mycelium effuse, floccose, persistent; conceptacles large, gregarious or disseminated, hemispherical, at length depressed and semi-immersed; appendages simple or interwoven with the mycelium; sporangia 20-24, ovate, pedicellate, with 8 spores.—On leaves of Grasses. Autumn. Frequent. ([Plate XI.] figs. 235, 236.)
Erysiphe Martii, Lk. Pea Blight; amphigenous; mycelium web-like, very often evanescent, globose; appendages short, interwoven with the mycelium; sporangia 4-8, globose, pedicellate, with 4-8 spores.—On leaves of Peas, Beans, Umbelliferæ, and other plants. Autumn. Very common. ([Plate XI.] figs. 237-239.)
Erysiphe Montagnei, Lév. Burdock Blight; amphigenous or hypophyllous; mycelium web-like, evanescent; conceptacles minute, globose, gregarious or scattered; appendages distinct from the mycelium; sporangia 8, ovate, rostrate, with 2-3 spores.—On leaves of Burdock. Not uncommon.
Erysiphe tortilis, Lk. Cornel Blight; hypophyllous; mycelium web-like, effuse, evanescent; conceptacles minute, globose; appendages ten times as long, free from the mycelium, flexuose; sporangia 4, ovate, rostrate, with 4 spores.—On leaves of the common Dogwood. Autumn. Frequent. ([Plate XII.] figs. 245, 246.)
Erysiphe communis, Schl. Buttercup Blight; hypophyllous; mycelium effuse, web-like, evanescent or persistent; conceptacles minute, globose, scattered or gregarious; appendages short; sporangia 4-8, ovate, rostrate, with 4-8 spores.—On leaves of various Ranunculaceæ, Leguminosæ, and other plants. Autumn. Very common. ([Plate XI.] figs. 240-242.)