id 
such as temperature and moisture, were eliminated, as far as 
possible, by germinating the seed under the most favorable con- 
ditions for penetration of the smut fungus. 
The results confirm those which have been obtained in previous 
years. While there were very marked differences in the rate of 
growth and development of the oat plants, there appeared to be 
no correlated variations in the infection results. 
ese investigations have been supported in part by a grant 
from the Penrose Fund of the American Philosophical Society. 
Studies on the Inheritance of Reststance of Oat Ilybrids to Loose 
and Covered Smuts 
Additional data were obtained on the third and fourth genera- 
tions of Hybrid 83, Canadian X Black Norway, Hybrid 84, 
Scottish Chief & Black Mesdag, Hybrid 85, Black Mesdag 
< Danish Island, and Hybrid 86, Monarch Selection & Goth- 
land. The results supplement the data obtained in previous 
years on the behavior of second and third generation plants of 
these hybrids. 
In collaboration with Mr. T. Rk. Stanton, Senior Agronomist, 
Division of Cereal Crops and Diseases, Bureau of Plant Industry, 
Washington, D. C., the results for some oat hybrids, obtained 
over a number of years, were published. Hybrid 61, Seizure 
X Victor, and Hybrid 62, Scottish Chief * Victor, were charac- 
terized by both parents being fully susceptible to loose smut, 
while one parent, Victor, was susceptible to the covered smut. 
A high degree of susceptibility to the loose smut was obtained 
in the second and third generations. With the covered smut the 
resistant quality appeared to be inherited on the basis of a single 
factor difference. Hybrid 63, Gothland & Monarch, Hybrid 64, 
Rossman * Monarch, Hybrid 65, Danish & Monarch, Hybrid 
67, Seizure X Monarch, and Hybrid 68, Monarch X Scottish 
Chief, involved crosses in which one parent was susceptible to 
loose smut and the other, Monarch, to the covered smut. The 
data indicated that resistance to the two smuts is inherited inde- 
pendently. The hybrids gave rather low percentages of infection 
with loose smut in the second generation, and there was also a 
shortage of resistant third generation families. The evidence, 
however, seemed to indicate that the inheritance of resistance to 
