New YorK AGRICULTURAL EXPERIMENT STATION. Th 
Filled this solution into one-half L. flasks, 285 Ce. in each 
flask, and thoroughly sterilized. 
Prepared a quantity of nitrogen free agar, to be referred to as 
“Special” No. 5 and also a quantity of nutrient agar “ Special ” 
No. 4. The latter is a medium found to be especially valuable 
in identifying the organism sought. A preliminary test proved 
the Special No. 5 to be superior to the nitrogen free agar recom- 
mended by Dr. Harding as it promotes a more rapid development 
of P. radicicola, although a nitrogen free medium. 
On Oct. 9 planted the bits of cotton in flasks labelled to corre- 
spond to number on package. Also planted two similar flasks 
with a vigorous pure culture of P. radicicola from Garden Pea, 
these latter flasks to be known as “ Check” I and II. 
Oct. 11, or forty-eight hours after planting bits of cotton, one- 
half per ct. of Ammonium Phosphate, dibasic, was added to the 
flasks. After twenty hours’ growth in the presence of Ammon- 
ium Phosphate, at which time the solution should have become 
decidedly turbid and ready to use as a practical product, sam- 
ples were drawn off by means of sterile pipettes and centrifuged 
and the sediments used in making smear stains. 
Proper dilutions from the eight flasks (8) were plated in Series 
I “Special ” agar No. 5 (nitrogen free) and in series II “ Special ” 
agar No. 4 (nutrient) at the end of forty-eight, seventy-eight 
and two hundred and sixty-four hours respectively. Allowed 
plates to develop ninety-six hours at a temeprature of 26° to 28° 
C. before recording results. At intervals of twenty-four, forty- 
eight, ninety-six, one hundred and twenty, one hundred and forty- 
four and two hundred and fifty-six hours respectively, the tur- 
bidity appearing in the eight flasks was recorded. ; 
“From the results of the above described methods of opera- 
tion the following summary for each sample has been collected: 
“Sample No. 28.—Faint milkiness in forty-eight hours. No 
change or increase until eleventh day, when contaminations 
predominated. Plates and slides revealed few molds and yeasts. 
No P. radicicola present. 
“ Sample No. 29.—Same as No. 28. Plates and slides, nearly 
pure culture of yeast. One bacteria and few molds. No P. 
radicicola present. 
