. =. 
New York AGRICULTURAL EXPERIMENT STATION. 83 
and sterilized in dry heat for two hours at 135 degrees C. Hach 
block received tj, cc. of a (1.51) bouillon culture prepared as 
follows: Ps. radicicola derived from the Department stock cul- 
ture was cultivated three days on 3.31 agar when a good growth 
had appeared. The growth from a single slope was carefully 
broken up in sterile water and transferred to 200 cc. of sterile 
(1.31) bouillon. At the end of three days the bouillon became 
faintly cloudy and one-half per ct. sterile ammonium phosphate 
was added. Nine days later, June 19, the bouillon culture was 
used for inoculation. 
A set of (3.31) agar plates was made to determine both the 
purity of the culture and approximately the number of germs 
placed upon each square of cotton. The plates developed a typi- 
cal growth representing a content in the (1.31) bouillon of 
13,000,000 per cc. and the addition of 650,000 to each square of 
cotton. , 
The Petri dishes containing the inoculated cotton were enclosed 
in paper bags and stored in a drawer in the laboratory. Here 
they were exposed to approximately the same dessication as 
would be experienced by the commercial packages. 
Between June 20 and July 6, fifty of the inoculated cotton 
Squares were examined. In the earlier examinations, a cotton 
block was placed in a Petri dish, 10 cc. of (1.51) agar was 
poured over the cotton, and the plate was gently agitated. Later 
the blocks were spread over the bottom of the dish with sterile 
needles and the agar added. On these fifty plates there was an 
average growth of three colonies. About one-half of these 
colonies resembled Ps. radicicola and the remainder were yeasts 
and chromogenic colonies, probably derived from the air while 
preparing the plates. Not a single colony developed on the 
last fifteen plates. 
The details of the first experiment were not entirely satisfac- 
tory. The bouillon culture used for inoculating the cotton was 
twelve days old and its vitality may have become reduced. The 
absorbent cotton may have undergone some treatment which 
rendered it unfavorable to germ life. The media were all pre- 
pared with distilled water which is not so favorable to germ 
growth as rainwater. 
