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takes place in the seedling stage from spores adhering to the grain. 
The infected plants, however, can not be detected until about the 
time for heading out, then one can observe the enlargement of the 
ovaries due to the unusual development of the parasite. The ker- 
nels are very much hypertrophied and constitute well-defined smut 
balls. These contain enormous numbers of the dust-like spores. 
These smut balls are broken in threshing and similar operations 
and the spores come in contact with the sound grain (Figs. 5a 
and 50). 
The Loose Kernel Smut of Sorghum.—the life history of the 
parasite causing loose kernel smut is somewhat similar to that of 
the covered smut, but its pathological effects on the host are strik- 
ingly different. The infected plants head out much earlier than 
normal plants and are noticeably dwarfed in nearly all varieties. 
They also show more tillering and branching as compared with the 
normal. Sometimes there is a marked enlargement of the glumes. 
The smut balls are much longer, more slender, and cylindric in 
shape. They break open very readily and permit the distribution 
of the spores. This rupturing of the membrane occurs even be- 
fore the smut ball has completely emerged from the glumes. The 
loose smut also is very widely distributed in the Sen ine 
areas of the world. It does not, however, appear to be as destruc- 
tive as the covered smut (Figs. 5b and 5c) 
The Head Smut of Sorghum.—The head smut of sorghum dif- 
fers from the sorghum smuts just mentioned in the fact that the 
entire head is more or less converted into a mass of smut spores. 
It does not seem to be so common as either the covered or loose 
kernel smut. In certain localities, particularly in Kansas and 
Texas, it is, however, common and destructive on some varieties 
of sorghums. It seems to depend for its distribution very largely 
upon spores in the soil, although seed-borne spores also are a factor 
in its distribution. This smut is particularly interesting from the 
fact that it occurs on maize as well as on sorghum (Fig. 6). 
The Common Maize Smut—This disease may be found practi- . 
cally wherever maize is grown, It occurs on the roots, stems, 
leaves, tassels, or ears. It is perhaps most conspicuous on either 
the tassels or ears, where it forms very characteristic hypertrophied 
