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involve Monarch, a variety highly susceptible to the covered smut 
and extremely resistant to the loose. It has been crossed with 
Rossman, Danish, Danish Island, Orientalis, and Scottish Chief, 
all resistant to the covered smut and susceptible to the loose. 
A number of additional crosses between certain varieties were 
made. These involve further new combinations of resistance to 
the two smuts of oats and when the studies are carried out on the 
second, third, and later generations, additional light should be 
thrown on the method of inheritance of the smut resistant quality. 
Some of our studies on the general problem of oat smut  in- 
vestigations are in cooperation with Mr. T. R. Stanton, Senior 
Agronomist of the Office of Cereal Crops and Diseases at Wash- 
ington, D.C. Mr. Stanton has furnished some of the material for 
the study of the hybrids, and is also testing out from the agronomic 
standpoint some of the lines which are promising on account of 
their smut resistance. 
Physiologic Races 
We have already demonstrated the existence of many specialized 
races of both loose and covered smut of oats. Recently an inter- 
esting specialized race of the covered smut has been isolated. The 
collections of the material were received from Mr. T. R. Stanton. 
The new race is particularly interesting because of its ability to 
infect the Fulghum variety of oats. This is a variety that is 
commonly grown in the Southern United States and has proved 
to be highly resistant to most other races of the covered smut. 
Of even greater interest is the fact that Black Mesdag is sus- 
ceptible to this newly discovered race of covered smut. Black 
Mesdag has for many years shown a very high degree of resistance 
to all collections of both loose and covered smut. Many distinct 
races of both smuts have been tried on this variety, but with 
negative results. It turns out, however, that the newly discovered 
specialized race of covered smut on the Fulghum type of red oats 
is capable of infecting Black Mesdag. 
Two different collections of the smut on Iulghum oats were 
made by Mr. Stanton and forwarded to me for investigation. ‘The 
spores from each collection were sown on twenty-four varieties of 
oats. One series of plants was grown in the greenhouse, and 
additional tests were made in the field following the discovery of 
