3 66 
Journal of Agricultural Research 
Vol. XXIII, No. S 
and later an incomplete pellicle forms. There is no change in the color 
of the medium when cultures are 3 months old. (The Lewis organism 
grows promptly in this medium without greening.) 
Gelatin stab. —With +10 beef-infusion gelatin, stab and plates, the 
liquefaction occurs slowly. Plates thickly sown show slight liquefaction 
in 7 days, and most of the plate liquefies in 12 days. Temperature 18.5° 
to 20 0 C. The liquefaction starts in the stab cultures in 6 days and 
continues slowly across the surface. In 1 month they are about one- 
fourth liquefied. In 2% months the stabs are slightly over half lique¬ 
fied. In 3 yi, months one stab was entirely liquefied and the others 
three-fourths. In 4X months all cultures are entirely liquefied. (The 
Lewis organism liquefies a stab culture in 4 weeks.) 
Lactose litmus agar. —Growth takes place readily. There is no 
color change in 5 days. In 7 days the bacteria have taken up color, 
and a mass on a platinum loop looks green. The slant has become 
blue, but the agar at the bottom of the tube has not changed color. 
In 16 days the color of slant is still blue; that part of the medium in 
the bottom of the tube is unchanged. (The Lewis organism reddens 
the medium.) 
Steamed carrot cylinders. —Growth does not take place quickly 
on carrot cylinders, but in 12 days the surface of each is covered with 
a creamy growth, smooth, wet shining, not viscid. There is no brown¬ 
ing of the medium in 25 days. (The Lewis organism browns the 
medium.) 
Steamed white Turnip. —Growth is slow in starting on this medium 
and is always thin. It is creamy in color, wet shining, not viscid. The 
medium is neither softened nor browned in 25 days. (Mr. Lewis says 
this medium is favorable for growth and that it becomes soft and 
brown.) 
Indol. —There is a slight production of indol in Dunham's solution 
cultures 10 days old. It is still slight when the cultures are 18 days 
old. The tests were made with sulphuric acid and sodium nitrite. 
(Like the Lewis organism.) 
Hydrogen sulphid. —Hydrogen sulphid is produced. The organism 
was grown on potato cylinders, beef agar, lactose agar, and in beef 
bouillon. The test was made by suspending lead acetate paper in the 
culture tubes. The paper became well blackened in every case. (The 
Lewis organism does not produce hydrogen sulphid in any of these 
media, not even after prolonged exposure.) 
Ammonia production. —The organism produces ammonia. Cultures 
of beef bouillon and peptone water both 10 days and 3 weeks old were 
tested with Nessler’s solution. Strips of filter paper were moistened 
with the solution and suspended in the tubes to be tested. The cul¬ 
tures were then heated in a water bath. A red-brown color appeared 
on the filter paper immediately. (Same as Lewis's organism.) 
Nitrate reduction. —There is no reduction of nitrates to nitrites. 
Tests were made with nitrate bouillon" in which the organism grew very 
well. Ten-day and 28-day cultures were tested. Bacillus coli grown 
in the same medium and tested by the same method (starch-iodin sul¬ 
phuric acid test) gave a positive test. (Same as Lewis’s organism.) 
Reduction of litmus. —Litmus is reduced in 10 to 15 days in sterile 
milk. (Not appreciably different from Lewis’s organism.) 
