102 UROMYCES 
On leaves of Phaseolus vulgaris. May, July—October ; 
even earlier on forced plants. Uncommon. (Fig. 55.) 
De Bary (J.c.) proved the genetic connection of the xcidia with the 
uredo- and teleutospores. The xcidia are rarely met with; they may 
occur either before or in company with the other spore-forms. I have 
seen no proof that they have been found in this country. The description 
is founded upon that of Sydow.| Fischer says that this species is very 
common in Switzerland on Piast it may become a dangerous parasite 
on forced Beans. All affected plants (leaves and stems) should be burnt. 
U. appendiculatus of Sydow, which occurs on many Leguminosz, is 
probably a collective species, though no experiments bearing on this point 
are available. \ 
DISTRIBUTION : as a collective species (U. appendiculatus) 
world-wide. a 
16. Uromyces tuberculatus Fckl. 
Ateidium Euphorbiae Gmel, in Linn. Syst. Nat. ii, 1473 p.p. Purton, 
Mid, Flor. iii. 293. Cooke, Handb. p. 537 ; Micr. Fung. p. 195 p.p. 
Plowr. Ured. p. 270. 
Cromyces excavatus DC. ; Cooke, Grevillea, ii. 161; Micr. Fung. p. 213. 
U. tuberculatus Fckl. Symb. Myc. p. 64. Sydow, Monogr. ii. 165. 
Fischer, Ured, Schweiz, p. 43, f; 33. 
U. proeminens Lév. ; Sace. Syll. vii. 553 p.p. 
Spermogones | 
Aicidiospores \ * 
whole leaf; secidia immersed, cup-shaped, with a short denticu- 
late margin ; spores orange, densely ver1.uculose, 17—25 x 14— 
20 p. 
Uredospores. Sori hypophyllous, scatte.-ed, at length naked, 
cinnamon; spores more or less 
globose, yellowish-brown, aculeo- 
late, 20—25 uw; epispore 14—2) 4 
thick, with 5—7 swollen germ- 
pores (45, Fischer). 
Fig. 56. U. tuberculatus. Two ma- Peleutosp Ores: Sori amphi- 
ture teleutospores; «, a teleuto- genous and on the stems, round, 
ice the tubercles are scattered or sometimes arranged 
in little groups, pulverulent, 
blackish-brown or black; spores globose to ellipsoid, occasionally 
Hypophyllous, svread uniformly over the 
