302 



XEX<>nornrs 



Spermogones. Epiphyllous, in little groups. 

 Uredospores. Sori of two kinds, primary epiphyllous, sur- 

 rounding the spertnogones, secon- 

 dary hypophyllous, scattered, small, 

 round, punctiforin, orange, sur- 

 rounded byafewclavato paraphyses; 

 spores spherical to obovate, finely 

 echinulate, reddish-orange, 20 — 

 23x14—20^. 



Teleutospores. Sori hypophyl- 

 lous, similar, but bright-brown; 

 spores cylindrical, fusiform or cla- 

 vate, of 2 — 7 (mostly five) cells, 

 ofte'n curved, thickened at the apex 

 like many Pucciniae, slightly con- 

 stricted, tapering below, smooth, 

 sienna-brown, 52 — 140 x 18 — 24 fi; 



epispore thin, with one germ-pore in each cell; contents orange; 



pedicels varying in length, persistent, not much widened below. 



On Potentilla Tormentilla (= P. erecta) and possibly on 

 other species of the genus. Very rare. September, October. 

 (Fig. 228.) 



This species resembles a Puccinia in some respects, especially in the 

 thickening of the apex of the teleutospores, and the position of the solitary 

 germ-pore of each cell ; the wall of each cell becomes darker upwards, the 

 lower cells being nearly colourless, and the uppermost a pale clear brown, 

 all quite free from any warts or projections. They can germinate in 

 autumn (September) like those of K. albida. Dietel says that the 

 uredospores and their mycelium can survive through the winter. 



Distribution : Europe, North America. 



Fig. 228. K. Tormentillae. 



Teleutospores. 



XENODOCHUS Schlecht. 



Autoecious. 



Caeomata large, indefinite, without paraphyses or peridium. 

 Uredospores absent, represented by the secondary smaller 

 casomata. Teleuto-sori similar, often on the same mycelium ; 

 teleutospores of very long chains of cells, not verrucose. 



