Fifth Annual Report. A 
as Sporotrichum, and while it naturally does a great service 
at times, we have not found it feasible to attempt its artificial 
dissemination. 
Sporotrichum seems to flourish through a wider range of 
meteorological conditions than Empusa, and would be the more 
likely to appear as a natural epidemic. 
III,—ARTIFICIAL CULTURES. 
We have attempted at various times since 1889 the culture of 
Sporotrichum on other media than the chinch-bug, such as po- 
tatoes, corn, beef-broth, etc., in the hope of producing the 
fungus in greater quantities, and of disseminating the infection 
more rapidly than is possible by means of fungus-covered bugs. 
These experiments had been confined to the laboratory, and had 
not given promising results. We determined at the beginning 
of the past season’s work to carry on experiments of this kind 
on a large scale in the open field, and at the same time to con- 
duct parallel experiments in the laboratory. Pint Mason fruit- 
jars were used in making the artificial cultures. A three-fourths 
inch hole was cut in the metal cover, and a zinc tube of the 
diameter of the hole was inserted into this and soldered flush 
with the upper surface. This is essentially as figured and de- 
scribed by Forbes, in Bulletin No. 58, issued March, 1895, the 
only difference being that we have the tube project into the jar 
instead of above it for convenience in sterilizing large numbers of 
jars at one time. Whole corn or sliced raw potatoes were put into 
these jars, the tubes were tightly plugged with baked cotton, 
and the jars were placed in a large steamer and steamed for two 
hours in the morning and two hours in the evening for three 
successive days. Then, with the usual precautions, the cotton 
plugs were withdrawn, and spores from pure plate cultures 
were inserted through the tube in cover and dusted over the 
corn or potato by means of a piece of platinum foil melted into 
the end of a glass rod. This was sterilized in the flame of a 
Bunsen burner at frequent intervals. In this manner we were 
able to prepare large quantities of material for our field experi- 
ments. 
To distribute the infection in the fields water was shaken up 
with the cultures in the jars. The water ina single jar holding 
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