ON WILLOW 339 



above where it is pierced by an evident laterally placed germ- 

 pore. 



Caeomata on Larix europaea ; uredo- and teleutospores on 

 Sulix Caprea, more rarely on S. aurita and other Salices. The 

 commonest species. (Figs. 254, 255.) 



The teleutospores germinate the following spring. They are distin- 

 guished from those of all the allied species by being thickened above. 

 Plowright remarks that the ca^oma is not uncommon early in the year on 

 Larch foliage, but is very inconspicuous and easily overlooked ; he found 

 the oecidiospores, in company with the uredospores on S. Caprea, at West 

 Malvern, June, 1900. But it is almost impossible to say, without experi- 

 ment, to which form of Melam psora any given caeoma on Larch is to be 

 assigned. 



Plowright's M. farinosa seems to be chiefly this species, but several of 

 the allied forms are continually recorded under the same name. The 

 reddish teleuto-sori on the upper side of the leaf, are distinctive and are 

 easily found by looking for them from September onwards. It may be 

 mentioned here that both uredo- and teleutospores of the Melampsoras on 

 "Willow and Poplar germinate readily : if the germinating uredospores are 

 placed upon healthy leaves and kept in a damp chamber, infection usually 

 follows in 7 — 10 days. 



2. Melampsora Euonymi-Caprearum Kleb. 



Uredo confluens var. Euonymi Mart. Flor. Mosq. p. 230. Cooke, 



Handb. p. 527. 

 U. Euonymi Cooke, Micr. Fung. p. 216. 

 Caeoma Euonymi Plowr. Ured. p. 260. 

 Melampsora Euonymi-Caprearum Kleb. in Pringsh. Jahrb. f. Wissensch. 



Bot. 1900, xxxiv. 358. Fischer, Ured. Schweiz, p. 489. 



Sperniogones. Flatly pulvinate. 



^Ecidiospores. Ca3omata mostly hypophyllous, bright-orange, 

 in elongated clusters on orange spots, \ — 1 mm. diam.; spores 

 oval, rarely oblong, 18 — 23 x 14 — 19//,; epispore thick (up to 

 5 p.), finely and densely verrucose. 



Uredospores. Sori hypophyllous, on discoloured spots which 

 show distinctly on the upper side, small, \ mm. wide, pulvinate, 

 single or in groups; spores mostly roundish, orange, 14 — 19 x 

 14 — 17/z, distantly echinulate without smooth spots; epispore 

 thin, or at times thickened (up to 4 jx), with several germ- 



22—2 



