146 
Journal of Agricultural Research 
Vol. XXV, No. 3 
STARCH AGAR 
There was no evidence of diastatic action on potato starch suspended 
in beef-peptone agar when tested with iodin. 
GELATIN PLATES 
Colonies appeared in about 36 hours and grew fairly rapidly. They 
were circular with entire margin. Liquefaction began shortly after the 
colonies appeared and in 3 days had produced saucer-shaped depressions 
6 to 7 mm. in diameter. 
GELATIN STABS 
Surface growth was abundant in 3 days. There was no growth in 
lower part of stab. Liquefaction began in about 3 days and was com¬ 
plete in 60 days in tubes containing 10 cc. of medium. It was crateriform 
at first, but later became stratiform. In tubes uniformly inoculated and 
incubated at 20° C. for 7 days, liquefaction advanced 10 mm.; in 10 days, 
15 mm.; and in 30 days, 27 mm. The liquefied medium was fluorescent, 
greenish, with heavy surface growth which when agitated, came down 
in flocculent masses, thus forming a heavy white precipitate. 
NUTRIENT BROTH 
In + 10 beef-peptone broth a thin fringed pellicle formed and dropped 
as a unit after 3 or 4 days. Uniform clouding began in 12 to 24 hours 
and became heavy and persistent within 3 to 4 days. A putrefactive 
odor was produced. Abundant precipitate was formed which was 
viscid on agitation. The medium turned yellowish green after 2 days 
and was alkaline to litmus. No hydrogen sulphid or ammonia was 
produced. Erlich's reagent showed a positive reaction for indol after 
4 days. 
POTATO CYLINDERS 
Growth on steamed potato cylinders was pale yellow in color, flat, 
spreading, and viscid. After 7 to 10 days the cylinders became a 
vinaceous buff color. 
MILK 
In plain milk there was no apparent coagulation, but a slight creamy 
consistency developed after 3 to 4 days. Peptonization began at the 
top after 2 days and was complete at the end of 12 to 14 days. A 
heavy white, granular precipitate developed. After digestion the 
medium was honey-yellow in color, of thin gelatinous consistency, and 
strongly alkaline. 
methylene blue milk 
The blue color was reduced in 2 or 3 days, but a pale olivine color 
appeared in the cleared, digested part after about 5 or 6 days. After 
about 1 month the medium became honey-yellow and viscous. 
litmus milk 
Alkaline reaction appeared before beginning of protein digestion and 
persisted until the litmus was reduced. 
cohn’s solution 
In Cohn’s solution there was no growth. 
