Hcicropnccinia. 1 6 



J 



Trichobasis linearis. Lev. Cooke, " Micro. Fungi," 4th edit., 

 p. 223, t. vii. figs. 143, 144. 



ALcidium hcrberidis, Pers. Berk., " Eng. Flor.," vol. v. p. 372. 

 Grev., t. 97; "Flor. Edin.," p. 446. Johnst., "Flor. Berw.," 

 vol. ii. p. 207. Sow., t. 397, fig. 5. Cooke, " Hdbk.," p. 53S ; 

 " Micro. Fungi," 4th edit., p. 195, t. i. figs. 7-9. 



Exsiccati. 

 Cooke, i. 24, 441; ii. 93, 121, 122, 124. Vize, "Micro. 

 Fungi Brit.," 453, 456 ; "Fungi Brit.," 76, 78. 



^cidiospores on Berberis vulgaris and Mahonia ilicifoliay 

 chiefly on the berries. May to July. 



Teleutospores on Triticum vulgare, j'epens, Secale cerea/e, 

 Dodylis glomerata, Feshtca gigantea, Alopecurus pratensis, Agrostis 

 alba, Avena sativa, elatior, July and August, and throughout the 

 winter. 



Biology. — The mycelium of all spore-forms is strictly localized. 

 The secidiospores on the berries oi MaJionia ilicifolia I found, in M ly, 

 1883, readily produced the uredospores on wheat in about eight or ten 

 days. This is a fungus which varies very much in frequency ; some 

 years almost every straw in a wheat-field is affected, in others scarcely 

 one can be found attacked. Certain conditions render the wheat plant 

 more susceptible to the parasite, foremost amongst which is a too large 

 supply of nitrogen, as evinced by the uniformity with which wheat 

 plants growing on manure-heaps are attacked with the parasite \ so 

 are the plants grown on the ground where a manure-heap has stood, 

 and also plants growing where an old ditch has been filled up, although 

 perhaps to a less degree. A very thin, or what is termed in some 

 parts of England " a gathering crop," one in which the plants are far ■ 

 apart, and which consequently throw out a large number of lateral 

 shoots, is also hable to beconie affected by the parasite. It is interesting 

 to remark that a Puccinia occurs on Berberis glauca in Chili, which 

 is accompanied by an /Ecidium. In some parts of Europe an^cidium, 

 having a perennial mycelium (^. magellianicinn, Berk, in Hooker's 

 " Flor. Antarctica," pp. i, 2. London ; 1844-1847), occurs on Berberis 

 vulgaris, which has been shown by Magnus to have a distinct life- 

 history. 



Puccinia coronata. Corda. 



y^cidiospores — Pseud operidia often on very large orange swell- 

 ings, causing great distortions on the leaves and peduncles, 



