34 Wisconsin Academy of Sciences, Arts, and Letters. 
the danger of infection from the gills. After the spores were 
discharged the pileus was carefully removed and the bell jar 
replaced the slides remaining on the racks until needed. Spores 
preserved in this manner remained pure for a year. 
A decoction of string beans, (about 392 grams to a liter of 
water) proved to be the best nutrient although a decoction of 
Coprinus and of dung was used for some forms. For the early 
stages in the development of the mycelium small cultures were 
made in dishes holding 10 c. c. of the nutrient solutions. Large 
quantities of spores were sown and at the end of 12, 24, and 48 
hours, the nutrient solution was removed by a pipette until only 
2 c. c. remained, the dish was then filled with fixing solution 
which would thus be reduced about one-fifth in strength. After 
fixing 24 hours the spores were stippled on the slide by the 
method described by Harper (11) in his paper on the nuclear 
phenomena in the smuts. 
Spores were also sown in thin films of agar-agar on sterilized 
slides. When the mycelium had attained the desired growth 
the entire slide was immersed in fixing solution. If the film 
loosened from the slide it was easily fastened again by a film of 
albumen. 
To obtain mycelia, cultures were made similar to those de¬ 
scribed by Falk (8). Rye bread cut in slices two or three inches 
thick were moistened in bean decoction and fitted into battery 
jars five inches deep by four wide. For covers petri dishes four 
and a half inches in diameter were used. A thin layer of cotton 
was placed between the cover and the dish to allow free circula¬ 
tion of air. Agar-agar plates were also used. 
The spores germinate in from six to eight hours and at the 
end of two or three days form a growth of mycelium which ap¬ 
pears as a white mat about a quarter of inch in diameter on 
the surface of the bread. The mat increases in size rapidly until 
it is two or three inches in diameter. At the same time there 
appear all over the culture small white dot-like masses of mycel¬ 
ium. These are new growths from oidia scattered from the 
first myc.elium. Falk has also described and illustrated such 
oidial colonies. These small secondary growths were removed 
