PUCCINIASTRUM 367 



Teleutospores. Sori hypophyllous, clustered or widely con- 

 fluent, {rnni. wide, covered by the epidermis, reddish, then 

 blackish-brown; spores shortly cylindrical or prismatic, 17 — 

 35 x 7 — 14 /x, those in the middle of the sorus Melampsora-like, 

 but at the periphery roundish or oval, and composed of 1 — 3 

 cells, i.e. divided by longitudinal walls; epispore clear-brown, 

 thickened (up to 3/x.) above, but with a thinner spot (? germ- 

 pore). 



[ . Ecidia on Abies pectinata, June, July ;] uredo- and teleuto- 

 spores on Epilobium {Chamaenerion) angustifolium, E. palustre. 

 August — October. Shere, Abinger, Surrey. (Fig. 274.) 



The recidiospores are distinguished from those of Calyptospora Goep- 

 pertiana by their smooth area and generally shorter length. The ascidium 

 of Mdampsorella Caryophyllacearum lives also on Abies pectinata, but 

 produces thereon witches'-brooms, and finally swellings and canker of the 

 branches, while P. pustulatum attacks the leaves only. Klebahn, Fischer, 

 and Tubeuf have all demonstrated experimentally the genetic connection 

 of the stages of this parasite, so far as concerns E. angustifolium ; but the 

 form on E. palustre and its allies is probably, at least biologically, distinct. 

 Klebahn's name, quoted above, includes only the form on E. angustifolium 

 and the allied E. Dodonaei. He restricts the name P. Abieti-Chamaenerii 

 to this, calling the form on E. palustre, E. montanum, etc. by the name 

 P. Epilobii, and assigns to them also certain small morphological differ- 

 ences. The collective species is common in North America, but the 

 secidium has not yet been recognised there. 



Distribution: Europe, North America. 



4. Pucciniastrum Pyrolae Dietel. 



JEcidium Pyrolae Gmel. in Linn. Syst. Nat. ii. 1473. 



Uredn Pyrolae Grew Flor. Edin. p. 440 p.p. Fischer, Ured. Schweiz, 



p. 539, f. 337. 

 Trichobasis Pyrolae Berk. ; Cooke, Handb. p. 529 ; Micr. Fung. 



p. 223 p.p. 

 Melampsora Pyrolae Schrot. ; Plowr. Ured. p. 247. 

 Pucciniastrum Pyrolae Dietel, in Engler u. Prantl, Nat. Pflanzen. 



i. 1**, 47. Arthur, N. Amer. Fl. vii. 108. 

 Thecopsora (?) Pyrolae Karst. ; Sacc. Syll. vii. 766. 



Uredospores. Sori hypophyllous, minute, hemispherical, 

 orange, on yellowish or purplish discoloured spots, surrounded 

 by the epidermis and by a peridium which both open at the 



