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MILDEWS, RUSTS AND SMUTS 
Teleutospores on Juniperus communis. 
Gymnosporangium juniperinum, Winter ; Plowr., Ured., 
P- 235 - 
Aecidia. On red or orange, more or less circular spots, 
cylindrical, curved, yellowish-brown, open and torn into 
shreds at the tip ;"spores subglobose, brown, hnely warted, 
21—28 X 20^—25 g.. 
Teleutospores. Spore masses at first dark brown, then 
orange, subglobose, gelatinous ; spores of two kinds, one 
kind spindle-shaped, with a thick, brown wall, 70—80 X 
25—30 p, the other yellow, with a thinner wall, 65—75 
X 16—20 p, with six germ-pores. Mycelium perennial. 
Aecidia on leaves of mountain-ash— Pyrus aucuparia. 
Teleutospores on Juniperus communis. 
Gymnosporangium confusum, Plowr., Ured., p. 232. 
Aecidia. Seated on thickened, more or less circular 
spots, orange, and often bounded by a red or brownish 
zone, cylindrical or cylindric spindle-shaped, splitting 
longitudinally and eventually torn into shreds ; spores 
subglobose, pale brown, minutely warted, 15—20 p diam. 
Teleutospores. vSpore mass at first knob-like, dark 
chocolate-brown, almost black, soon becoming cylindrical, 
often flattened, finally rich chestnut-brown, swelling when 
moist, and soon covered with golden-yellow promycelium 
spores ; spores smooth, i-septate, oval or elliptical, ends 
generally sharp, some spores have a colourless wall and 
orange contents, others have dark brown, thick walls, 
40—50 X 20—25 p, from 2—4 germ-pores, pedicel long, 
colourless. 
Syn. Aecidium mespili, D.C. 
Aecidia on hawthorn— Crataegus oxyacantha; medlar— 
Mespilus germanica ; quince— Pyrus vulgaris. 
Teleutospores on Juniperus sahina. 
Often confounded with Gymnosporium sabinae, which 
the present closely resembles, and appears to depend mainly 
for its specific identity on not being able to infect pear leaves. 
Plowright points out, that when the aecidia occur on 
hawthorn, the spermogonial spots are more brightly coloured 
than those of G. clavariaeforme. The aecidiospores are 
also slightly smaller than those of the last-named species, 
and the cells of the peridia are delicately reticulated and 
longitudinally wrinkled. The mycelium of the teleutospore 
stage is perennial. 
