80 
Research Bulletin No. 1 
Sound tubers, previously sterilized with corrosive sublimate, 
were placed in contact with thoroly rotted tubers. In not a 
single case did infection of the sound tubers result. 
Inoculum was placed over lenticels and over the "eyes" but 
no infection resulted in any of the varieties. In no case did in- 
fection occur. 
Sound tubers were sterilized with corrosive sublimate and 
inoculated thru a wound. None of the varieties mentioned above 
escaped infection but there was evident some slight difference as 
to the extent of the rotting in the different sorts. These results 
fully confirm those previously secured. (See Plates I to XII.) 
OTHER INOCULATIONS. 
In the winter and spring of 1911-1912 experiments were con- 
ducted to determine the comparative resistance of aerial stems of 
various varieties of potatoes to the invasion of Fusarium tuberi- 
vorum. The following sorts were obtained from Colorado thru 
the kindness of P. L. Fitch of the Colorado Experiment Sta- 
tion : 
1. Raleigh 8. Norton's Beauty 
2. Early Rose 9. Gold Coin 
3. Burbank 10. Pearl 
4. White Ohio 11. Green Mountain 
5. Early Ohio 12. Spaulding's Rose 
6. Russet 13. Beauty of Hebron 
7. Bliss Triumph 14. Snowflake 
From Minnesota, thru the kindness of A. R. Kohler, were 
secured tubers of the following sorts : 
1. Raleigh 2. Early Ohio 
These tubers, previously sterilized by soaking in corrosive 
sublimate solution (1 to 1000) for one-half hour, were planted in 
soil which had been previously sterilized by steaming in pots 
which had been sterilized with formalin solution. These pots 
were kept in the greenhouse and watered, as need arose, with 
distilled water. 
When the plants had attained a height of about 30 to 35 
cm. inoculation was attempted. In each pot some stems were 
wounded quite deeply with a sterile scalpel before the inoculum 
was applied. This inoculum consisted of a mixture of spores, 
hyphae, and glucose agar. Other stems were merely smeared 
with the inoculum without previous wounding. Four stems in 
each pot were used for the experiment, two with wounds and two 
without wounds. The humidity of the atmosphere in the green- 
