ON POLYGONACE 115 
0. Rumicis Wint. Krypt. Fl. i. 145. Plowr. Ured. p. 135 p.p. Sace. 
Syll. vii. 544, Sydow, Monogr. ii. 238. Fischer, Ured. Schweiz, 
p. 9, f. 8. 
Uredospores. Sori amphigenous, on coloured spots, round, 
minute, scattered, soon naked, — 
pulverulent, cinnamon; spores 
subglobose to ellipsoid, sparsely 
echinulate, pale-brown, 20—28 x 
18—24 yw, with two (more often 
three) germ-pores. eo Fig. 67. U. Rumicis. Teleuto- 
Teleutospores. Sori similar, spores and uredospore, on R. 
but darker; spores subglobose to oe 
pyriform, with a hemispherical hyaline papilla, often narrowed 
below, smooth or nearly so, brown, 2435 x 18—24 4; epispore 
rather thick ; pedicels thin, hyaline, deciduous. 
On Rumex conglomeratus, R. crispus, R. Hydrolapathum, 
R. nemorosus, R. obtusifolius, and perhaps others. May— 
September. Common. (Fig. 67.) 
The spots on the leaves are small, round, and of various colours ; often 
the chlorenchyma in the immediate neighbourhood retains its green colour 
long after the rest of the leaf has become faded and yellow. 
It will be noticed that the spores of U. Rumicis are exactly like those 
of U. Ficariae, and for this reason Tranzschel was led to suspect some 
connection between the two, such as he demonstrated to exist between 
P. fusca and P. Pruni-spinosae, whose teleutospores are equally alike. In 
1905 he reported that he had produced an ecidium on Ranunculus Ficaria 
from the spores of U. Rumicis; still later, he repeated this statement 
(1909), and added that he had infected Rumex obtusifolius with xcidio- 
spores from &. Ficaria. Other experimenters (Bubék, Krieg) have been 
unable to repeat the former of these infections ; they could only produce 
the ecidium on &. Ficaria with the spores of Uromyces Poae. It has 
been suggested that there are two ecidia on &. Picaria, one belonging to 
U, Poae and the other to U. Rumicis; I have tried to infect 2. obtusefolius 
with ecidiospores from &. Ficaria, brought from a place where the ecidium 
on it and the Uromyces on &. obtusifolius were both very abundant, but 
the attempt, failed, Krieg (Centralbl. f. Bakt. 1906) obtained uredo- 
spores on &, Acetosa with ecidiospores from &. Ficaria, but the same 
material infected species of Poa (especially P. trivialis), and the possibility 
8—2 
