CHAPTER XVIII 
FUNGI 
In recent years such progress has been made in culture methods 
for fungi, especially for those which cause disease, that only the trained 
pathologist could be expected to know just what is the best medium 
for each particular fungus. We shall not attempt to deal with the 
subject of culture media, but shall simply indicate how a student, 
not trained in pathology, may secure material for preparations. 
Professor Kleb’s methods make it possible to secure material of 
many forms in various phases of their life-histories. 
In general, filamentous fungi are treated like the filamentous 
algae, while the fleshy forms are cut in paraffin. 
PHYCOMYCETES 
Rhizopus (Mucor).—This familiar mold appears with great 
regularity on bread. The following is a sure and rapid method for 
obtaining Mucor: Place a glass tumbler in a plate of water, put on 
the tumbler a slice of bread which has been exposed to the air for 
a day, and cover with a glass j ar. The bread must not become too wet. 
To obtain a series of stages in the development of the sporangium 
it is better to use living material. For class work, time the cultures 
so as to have a plenty of sporangia which have not yet begun to 
turn brown. 
For permanent preparations, fix for at least 24 hours in 10 per cent 
formalin; wash J hour in water, and then follow the Venetian turpen¬ 
tine method. Eosin gives good results. Stain over night or 24 
hours, treat with 2 per cent acetic acid, changing several times, and 
then put into glycerin, merely pouring off the 2 per cent acetic acid 
and not rinsing the acid out in water. When washing out the glycerin, 
do it with alcohol which has about 0.5 c.c. of acetic to the 100 c.c. 
of alcohol, and leave 1 or 2 c.c. of this slightly acid absolute alcohol 
on the material when you add the 10 per cent Venetian turpentine. 
For permanent preparations, fix for at least 24 hours in the special 
chromo-acetic-osmic solution; wash 24 hours in water and follow 
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