New YorRK AGRICULTURAL EXPERIMENT STATION. DT 
SEARCH FOR PS. RADICICOLA ON DEPARTMENT COTTON. 
Having failed to secure an authentic culture of Ps. radicicola, 
but having the directions for properly isolating the culture, 
recourse was had to the cotton sent out from the Department at 
Washington as the most reliable source for obtaining the desired 
organism. . 
April 18, Prof. Stone kindly placed at our disposal a package 
which he had received from Washington approximately two 
weeks previous to that date. It was stamped “Alfalfa. Culture 
No. 256.” The cotton in this package was wrapped in layers of 
paper and this in tinfoil. The package was sealed by the label 
which was intact at the time we received it. 
At each examination the package was carefully opened under 
conditions which would offer the smallest practical opportunity 
for contamination. After removing the desired sample of cotton 
with sterile instruments, the remainder was carefully returned 
to the package. This and all the other packages were held in 
our stock culture room at approximately 17° C. (65° F.) when 
not being used in the laboratory. 
First attempt.—We assumed that Ps. rad icicola was present on 
the cotton in immense numbers. In such a case a short soaking 
in water would loosen quantities of them so that they might be 
recovered by plate methods. 
On April 12, a portion of the cotton, the size of a small test 
tube plug, was placed in sterile water for two hours and repeat- 
edly shaken. An ordinary platinum loop of this water was then 
plated in (8.20 and 3.31) agar. On April 22, no growth had 
appeared on any of the plates except a few molds and a few 
chromogenic bacteria, evidently not Ps. radicicola. 
Second attempt.—By April 17, it had become evident that no 
satisfactory growth was appearing on the first set of plates. 
The sample of cotton had now been five days in the sterile water 
with no evidence of growth. Thinking that food material 
might induce some development, 5 cc. of (1.00) bouillon was 
now added. Two days later plates were made as before, using 
(3.20 and 3.31) agar. At this time there was.a slight turbidity 
in the finid surrounding the cotton and a hanging drop 
examination under the microscope showed germ life to be fairly 
