MILDEWS, RUSTS AND SMUTS 
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producing a promycelium, bearing minute secondary, or 
promjmelial spores. 
The bundles of teleutospores resemble stout, yellowish- 
brown hairs projecting from the infected leaves. 
Cronartium ribicolum, Deitr. 
Aecidia. Large, bursting through the bark in great 
numbers, eventually rupturing and liberating a powdery 
mass of orange spores. One part of the spore wall is smooth, 
the remainder warted. 
Uredospores. Elliptical or ovoid, orange, aculeate, 
19—35 X 14—22 (JL. 
Teleutospores. Forming a yellowish-brown column spring¬ 
ing from the centre of the sorus of uredospores ; spores 
I-celled, elongated, germinating in situ. 
Syn. Peridermium strobi, Klebahn. 
The aecidia occur on the trunk and branches of Pinus 
strobus, the Weymouth pine ; P. cembro and P. lambertiana. 
The uredospores and teleutospores on the under surface 
of living leaves of black currant— nigrum. 
Often proving very injurious to conifers. 
Cronartium flaccidum, Winter. 
Uredospores. Variable in form, pale orange, aculeolate, 
elliptical or ovate, 20—30 X 13—20 p. 
Teleutospores. Forming cylindrical or hair-like sori, 
often curved, pale brown ; spores oblong or cylindrical, 
i-celled, ends blunt, brown, 8—12 (jl broad. 
Syn. Cronartium paeoniae, Cast. 
Aecidial stage unknown. 
The teleutospore and uredospore stages grow on living 
leaves of various species of cultivated paeonies, as Paeonia 
officinalis, etc. 
ENDOPHYLLUM, Lev. 
Teleutospores. Forming a sorus enclosed in a peridium 
or wall composed of sterile cells ; spores produced in 
basipetal chains ; germinating by the formation of promy¬ 
celium, which bears secondary or promycelial spores. 
Aecidia and uredospores unknown. The teleutospores 
resemble in general appearance, an aecidium, being sur¬ 
rounded by a wall, or peridium, and the spores are produced 
in basipetal spores as in Aecidium, but the germination 
resembles that of the teleutospores in other genera. 
Endophyllum sempervivi, Lev. 
Pyncidia. Globose then conical, honey-colour, 
