ON POLYGONACE.E 117 



On the same host-plants is a Puccinia, which (in the absence of the 

 teleutospores) can be distinguished only by the fact that the uredospores 

 have two (rarely three) germ-pores and are adorned with few and distant 

 spines. There is little doubt that many of the specimens recorded as 

 U. Acetosae are really the uredospores of Puccinia Acetosae. 



Distribution : Germany, France, Sweden, Norway, Finland. 



29. Uromyces Polygoni Fckl. 



JEcidium aviculariae Kze. ; Cooke, Handb. p. 545 ; Micr. Fung. p. 1 99. 

 Puccinia vaginalium Link ; Cooke, Handb. p. 495 ; Micr. Fung. 



p. 204. 

 Trichobasis Polygonorum Berk. ; Cooke, Micr. Fung. p. 226 p.p. 

 Uromyces Polygoni Fckl. Symb. Myc. p. 64. Cooke, Handb. p. 519 ; 



Micr. Fung. p. 213. Plowr. Ured. p. 123. Sacc. Syll. vii. 533. 



Sydow, Monogr. ii. 236. Fischer, Ured. Schweiz, p. 61, f. 46. 



McAlpine, Rusts of Australia, p. 99, f. 150 — 1. 



ftpermogones. Honey-coloured, conical, only a few together. 



sEcidiospores. Mostly hypophyllous, on yellow or violet 

 spots, irregularly aggregated or in circular groups, cup-shaped, 

 whitish, with a cleft and revolute margin; spores verruculose, 

 yellowish, 15—21 x 14— 18/*. 



Uredospores. Sori amphigenous or on the stems, scattered 

 or in small clusters, small, round, soon 

 naked, pulverulent, cinnamon ; spores glo- 

 bose to ellipsoid, densely and minutely 

 verruculose, pale-brown, 18 — 26 x 17 — 24 fi; 

 epispore 1| — 2| /x thick, with three or four 

 germ-pores. 



Teleutospores. Sori like the uredo- 

 sori, but larger and more confluent upon pj ff 69 jj Polygoni. 



the stems, compact, dark-brown : spores Teleutospores, on P. 



tit i aviculare. 



globose or obovate, rounded above and 



thickened (up to 6 //.), smooth, chestnut-brown, 22 — 38 x 14 — 



22 /j, ; pedicels coloured, persistent, thick, as much as 90 /u, long. 



On Polygonum aviculare. /Ecidia, rare, May — June, Man- 

 chester (T. Brittain), 1875 ; uredo- and teleutospores, very 

 common, July — November. (Fig. 69.) 



