PEEISPOEIACEI. 651 



** Sporangia 3-8 spored. 



1926. Erysiphe graminis. D.C. '-Grass Blight."' 



AmphigenoiTs or epiphvlloiis ; mycelium effuse, floccose, per- 

 sistent ; conceptacles large, gregarious or disseminated, hemis- 

 pherical, at length depressed and semi-immersed; appendages 

 simple or interwoven with the mycelium ; sporangia 20-24, 

 ovate, pedicellate, with 8 spores. — Lev. Ann. Sc. Xat. 1851, xv. 

 p. 165, 1. 10,/. 33. Cooke JI.F. t. xi. /. 235, 236. A^/res. exs. no. 

 23. Till Carp. i.p.212. FcJd.exs.no. 659. 

 On leaves of grasses. Autumn. 

 The conidiiferous condition of this species is Oiclium monilioides. Link. 



1927. 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. — Lev. Ann. Sc. 

 Nat. 1851, XY. p. lCj6,t. 10, f.S4:. Cooke M.F. t. xi. /. 237-239. 

 Cooke exs.no. ^Q. FcM.exs.no. ^^0-Qll. E. pisi. Tul. Carp.i. 

 p.216,t. 5,/. 7, a. b. E. communis. Eng.FLy.p.32b {partly). 



On leave of peas, beans, UmhelUferce, &c. Autumn. Com- 

 mon. [^P- Carolina.] 



1928. Erysiphe Montagnei. Lev. " Burdock Blight." 



Amphigenous or hypophyllous ; mycelium web-like, evanes- 

 cent; conceptacles minute, globose, gregarious or scattered; ap- 

 pendages distinct from the mycelium ; sporangia 8, ovate, ros- 

 trate, with 2-3 spores. — Lev. Ann. Sc. Nat. 1851, xv. p. 169, t. 

 11,/. 36. Cooke M.F. p. 220. Cooke exs. no. ^1 . Fckl.exs.no. 

 673, 674. E. communis. Eng. Fl. v. p. 325 {partly). 



On leaves of Burdock. 



1929. Erysiphe tortilis. Lk. " Cornel Blight." 



Hypophyllous ; mycelium web-like, effuse, evanescent ; con- 

 ceptacles minute, globose ; appendages ten times as long, free 

 from the mycelium, flexuose ; sporangia 4, ovate, rostrate, with 

 4 spores. — Lev. Ann. Sc.Nat. 1851, xv.^. 170, 1. 11,/. 35. Cooke 

 M.F. t. xii./. 245, 246. Cooke exs. no. 98. Eng. Fl. v. p. 327. 

 Tul. Carp. i. j9. 213. Fckl. exs. no. 672. Berk, exs. no. 204. 



On leaves of common Dogwood. Autumn. 



