o7 
The variety Marquis, which has some reputation as being more 
or less resistant to bunt, gave 33.3 to 62.9 per cent. infection with 
the four races of Tilletia laevis and 51.7 to 89.2 per cent. with 
the five races of T. tritici. The variety Florence, also considered 
a more or less resistant variety, gave percentages of infection 
varying from 18.7 to 53.8 with 7. laevis and 11.7 to 66.6 with 
LE UCT 
It is interesting to note that only one variety—Hope—which 
has been developed at the North Dakota Agricultural Experiment 
Station, has proved to be resistant to all of these ten races of bunt. 
Sorghum smut investigations 
The study on the behavior of various sorghum hybrids to the 
covered kernel smut was continued. Many of the data were ob- 
tained with the second generation and other data with the third 
generation. The results were in line with those previously se- 
cured. A large number of first generation plants of different 
sorghum hybrids were grown. ‘These crosses were made in 1927 
and, for, the most part, involved resistant and susceptible parents. 
During the coming year the second generation plants of these 
crosses will be grown, and they should prove valuable in the study 
of the mode of inheritance of covered kernel smut. 
Forest Pathology 
By ArTHUR HARMOUNT GRAVES 
Chestnut Bark Discase Investigations 
Continuing the work on the causes of the greater resistance of 
the roots of the chestnut as compared with the stems, to the fun- 
gus causing the bark disease, a new series of inoculations was 
made at Hamden, Connecticut, on June 18, 1928. Healthy roots 
and stems of approximately similar diameters were inoculated 
with the fungus, in all cases the part of the root inoculated being 
left exposed to the air. The main purpose of this work was to 
obtain material for microscopic study, so that if possible it may 
be determined whether there is any cause, based on the anatomical 
structure of the root, for its greater resistance. These inoculated 
