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THE PLANT WORLD. 
somewhat older stage search for minute black bodies which are 
often thickly scattered over the affected parts of the leaf and are 
especially prominent on the white mycelium. They can be seen 
with the unaided eye. Examine these with a hand lens. There 
will be seen slender black branches or “ appendages ” bristling 
all round the black body which is the fruit body. If it is on the 
lilac, choke cherry, or oak these appendages will be forked several 
times at the end in a dichotomous manner with recurved tips; 
if on the willow or elm they will probably be coiled at the tips. 
These fruit bodies contain inside delicate sacs, each of which con¬ 
tains several spores. These are known as the winter spores. 
They live through the winter and reproduce the fungus again in 
the spring, while the conidia are the summer spores and serve to 
propagate and spread the fungus during the summer. 
The Black Fungi. 
These have black fruit bodies which are more or less flask¬ 
shaped. The mycelium in most cases lives inside the hosts or 
substratum on which the fungi grow. The fruit bodies in some 
are scattered, and immersed more or less in the substratum, or are 
free on it; in other cases the fruit bodies are crowded together, 
or sunken in black crusts of mycelium; or in still other cases there 
is a mycelium body, or stroma, which is elongated and elevated 
from the substratum like a club, or branched, resembling the 
“ fairy ” clubs in shape. The fruit bodies here are immersed in 
these clubs or, more rarely, rest on the outside. Some of these 
fungi are parasitic, but a large number of them grow on dead 
wood, leaves, etc. 
The black knot (Plowrightia morbosa) forms knots on the 
limbs of plums and cherries. During the winter examine these 
knots with a hand lens to see the crowded, black, roundish fruit 
bodies. These contain the winter spores which are ripened 
usually in February. In June examine the knots with a lens and 
note the velvet-like covering. This velvet-like growth consists of 
numerous erect black branches of the mycelium which bear sum¬ 
mer spores. 
The black rot of grape is one of the black fungi. In the woods 
