wn 
— 
loose smut is dominant in inheritance. In the covered smut 
series, 131 plants were inoculated and 10 (7.6 per cent.) were 
infected. In this hybrid also a few infected second generation 
plants were observed; in view of the moderate susceptibility of 
Danish Island to the covered smut, this result might be expected. 
Hybrid 86, Monarch Selection & Gothland, is a cross between 
two varieties very susceptible to the loose smut and _ highly 
resistant to the covered. There were 163 second generation 
plants inoculated with the loose smut and 152 (93.2 per cent.) 
were infected. Thus, the second generation plants were as 
susceptible as the parental varieties. There were 166 second 
generation plants inoculated with the covered smut, and none 
was infected. The complete resistance of the parental varieties 
to this smut appears in the second generation. 
Experiments with the Third Generation of Oat Hybrids.—In the 
last Annual Report, the data for the second generation of Hybrid 
79, Canadian * Monarch, Hybrid 80, Canadian * Monarch 
Selection, Hybrid 81, Gothland & Black Mesdag, and Hybrid 82, 
Danish Island & Monarch, are recorded. During the past year, 
many third generation progenies of each of these hybrids were 
grown. Usually, one series of plants of each progeny was inocu- 
lated with the loose smut, and a parallel series with the covered 
smut. 
The parental varieties of Hybrid 79, Canadian and Monarch, 
are both very susceptible to the covered smut, and in the second 
generation the percentage of infection was 98.8. There were 52 
third generation progenies inoculated with the covered smut, and 
all of these showed a very high percentage of infection. There 
was a total of 796 plants, of which 752 were smutted. Thus, the 
susceptibility of the two parents appears in both the second and 
third generations. 
Canadian ts very susceptible to the loose smut, while Monarch 
isresistant. In the second generation, 39.3 per cent. of the plants 
inoculated with the loose smut were infected. There were 336 
third generation progenies grown, of which 228 descended from 
uninoculated second generation plants. These progenies were 
classified as 29 resistant, 87 susceptible, and 112 segregating, the 
latter progenies giving a comparatively low percentage of infec- 
tion. 
