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slight to deserve attention. When we consider that it takes 
as much nourishment to mature a head of smutted oats as one 
of healthy grain, and that this disease causes an annual loss in 
the United States estimated at $15,000,000, we begin to realize 
its economic importance. The life history of the oat-smut is 
very similar-to that of the corn, but its methods of infection are 
quite different. The spores are not produced in such great quan- 
tities and the chances of the young plants becoming infected by 
the spores in the soil are comparatively slight. In thrashing the 
grain the spores of the smut are thoroughly distributed among 
the healthy seeds and, being very small, readily cling to the husks 
which surround the seed of the oat. If these seeds are planted, 
the seed of the host and the spores of the fungus germinate 
ean and, being in close contact, the young plant is easily 
infected. 
The greater part of the loss occasioned by oat-smut is unneces- 
sary for this is one of the diseases which is very easily controlled. 
It has been found that it is possible to treat the seed of oats with 
formaldehyde or hot water in such a way as to destroy the spores 
of the fungus which may cling to the seed without injuring the 
life of the seed itself, and since the main source of infection of 
this disease is idl the seed this means of control has proved 
very effectiv 
WILT DISEASE OF WATERMELON AND COTTON. 
In places where the waco is cultivated extensively much 
watermelon-wilt. This disease is characterized by the wilting 
of the foliage which results in the death of the plants. In the 
watermelon as in other higher plants the water necessary to 
supply the forming fruit and the growing leaves as well as that 
lost by evaporation through the leaves is taken up from the soil 
and conducted through the stems to the place where it is to be 
used or evaporated. If we examine a section of the stem of a 
watermelon vine we find numerous large ducts which serve this 
purpose. Those who have made a study of the watermelon-wilt 
. disease have found that this is caused by a fungus which grows 
