It seems that another experimenter, whom I will quote, has succeeded scarcely as well. Mr. G. P. Clinton, the assistant Botanist of the Illinois Experiment Station, Urbana, Illinois, in Bulletin No. 57 (March, 1900) reports as follows: “Apparently from the experiments of Kellerman, infection takes place through the germinating seed, though the per cent. of infection he produced was rather small. In ’98 field experiments were conducted here with a view of infecting the Orange variety of sorghum with this smut. In one case the seed was mixed with an abundance of spores and in others these spores were sprayed in water or manure water on the young parts of the plants when about six inches high. In none of the several hundred plants that matured was any sign of the smut found. It is very likely that the variety used may have had something to do with the negative results, as it was not the same from which the smut was taken.”
The head-smut of sorghum is not to be confused with another species that occurs on the same host. The one now referred to is a grain-smut, that is, the panicle as a whole is not included, but the individual grains become smutted. This species has been called _Ustilago sorghi_, but Mr. Clinton regards it as a Cintractia, namely, _Cintractia sorghi-vulgaris_ (Tul.) Clint. It is more common than the former, occurring often on sorghum and broom corn.
The head-smut of sorghum, _Ustilago_ or _Cintractia reiliana_, was first found in this country by Prof. J. T. Willard at Manhattan, Kansas, in 1890, in a plot grown for purposes of chemical investigation. The same year it was detected by Dr. Halsted in New Jersey. I found it in Ohio in 1897 and it is now reported for Illinois by Mr. Clinton. In all these cases it occurred only on sorghum, but Prof. Hitchcock has reported it as not uncommon on maize in fields about Manhattan, Kansas.
Illustration: _Plate_ 2: KELLERMAN ON SORGHUM SMUT.
EXPLANATION OF PLATE 2.—Ustilago or Cintractia reiliana. Figure 1: The foliicolous form occurring on sweet-corn, the panicle not yet emerged, but the smut on upper leaves in sight. Figure 2: Same as in Figure 1, showing a later stage of maturity. Figure 3: An infected sorghum plant in the greenhouse, photographed in 1899, the panicle smutted. Figure 4: An infected sorghum plant, grown in the greenhouse in 1900, the central panicle sound, the later (side) panicles smutted.