i8 MILDEWS, RUSTS AND SMUTS 
\epilohii, Schroet. Conidia shortly elliptical, 15—21 X 
14—18 pL; oospore, 25—^35 [x diam. On Epilohium 
palustris and E. parvifloraJ] 
\heliocarpi, Lagerh. Conidia elliptical, warted at the tip, 
30—40 X 24—30 [X. On Heliocarpus americanus]. 
[obducens, Schroet. Conidia broadly elliptical, with a 
wart at the tip, 16—21 X 12—15 [x ; oospore globose, 
25—30 fx diam. On Impatiens fulva, covering the 
under surface of the cotyledons.] 
[celtidis, Berl. Conidia elliptical, 26—30 X 14—20 (x ; 
oospore, 28—36 x 30—44 (x. On Celtis occidentalis!\ 
[australis, Swingle. Conidia broadly elliptical, 14—17 
X 10—13 [X. On leaves of Cyclanthera hystrix.'] 
[ribicola, Schroet. Conidia elliptical, 15—20 X II—13 
(X. On leaves of Rihes ruhrum.'] 
[halstedii, Berl. and De Toni. Conidia broadly elliptical, 
25—30 X 15 —20 [x. On leaves of various plants 
belonging to the Compositae. Ambrosia, Bidens, 
Rudbeckia, Silphium, Helianthus, Solidago, etc.] 
Plasmopara pygmaea, Schroet. Forming pale spots on 
the leaf, the tufts of conidiophores effused, whitish, my¬ 
celium thick, irregularly constricted here and there, haus- 
toria minute, mostly pear-shaped ; conidiophores tufted, 
emerging through the stomata, somewhat spreading from 
the base, 100—170 x 8—15 pi, often slightly thickest up¬ 
wards, with a few short, rather stout conidia-bearing 
branches near the tip, the branches sometimes bearing 
2—3 short branchlets, which are abrupt or truncate at the 
tip, after the conidia have fallen away ; conidia broadly 
elliptical, with a papilla at the tip, size variable, 18—28 
X 15—22 pi, colourless ; oospore globose, smooth or min¬ 
utely rugulose, wall thin, wall of oosphere thick, yellowish, 
45—55 [I thick, producing zoospores on germination. 
Syn. Peronospora pygmaea, Unger. 
On leaves of various ranunculaceous plants, as Wood ane¬ 
mone (Anemone nemorosa), and other species of Anemone, 
Aconitum, Hepatica, Isopyrum, Thalictrum, etc. 
Forming minute whitish tufts that in course of time 
become greyish brown. The conidiophores are often 
unbranched and furnished near the tip with 2—5 short 
spine-like outgrowths bearing the conidia. 
Plasmopara pusilla, Schroet. Forming effused whitish 
patches, conidiophores in tufts up to 20, emerging through 
