6 
Journal of Agricultural Research 
Vol. IX, No. i 
Reduction of nitrates. —Nitrates are not reduced. Five-day-old cultures tested 
both by the starch potassium-iodid test and by the sulphanilic-acid alphanaphthyl- 
amin test gave no color reaction. 
Production of indol. —Tests made at the end of the tenth day on cultures in Dun¬ 
ham ’s peptone solution gave a strong indol reaction. The cultures tested with the 
sodium-nitrite sulphuric-acid reaction gave a strong pink color very quickly, while 
control tubes treated similarly remained uncolored. 
Toleration of acids. —Neutral peptone-beef bouillon, to which were added o.i, 
0.2, 0.3, and 0.4 per cent, respectively, of citric, oxalic, and tartaric acids, was inocu¬ 
lated. After five days a moderate growth was visible in the cultures containing 0.1 
per cent of all the acids used. This growth increased and was quite strong at the end 
of the fifteenth day, but in none of the 0.2, 0.3, or 0.4 per cent strengths of any of the 
acids was clouding visible, although kept for 30 days. 
Toleration of sodium hydroxid. —The organism is quite sensitive to alkali. 
Peptone-beef bouillon titrated according to Fuller’s scale to the following strengths: 
+35, -j-30, +20, +15, 4-io, 4-$, neutral, —5, —10, —20, and —30, were inoculated 
from a 24-hour-old +10 bouillon culture. Growth was apparent and vigorous in the 
4-10 and 4-15 bouillon on the second day, and was also apparent, although scanty 
in those titrated to neutral, 4-5, and -F20. On the third day tubes of —5 bouillon 
became slightly clouded and on the eighth day —10 bouillon and 4-30 bouillon showed 
a very scanty, scarcely visible clouding. Clouding in the —20 bouillon was not 
visible until after the tenth day, but on the twentieth day was easily apparent. 
Growth was never visible in the bouillon titrated to 4-35 and —30. The best growth 
took place in the 4-15 bouillon. 
Hydrogen sulphid. —Strips of filter paper soaked in a saturated solution of lead 
acetate were suspended over cultures of the organism in a -f 10 peptone-beef bouillon. 
No browning of the paper was visible during five weeks’ exposure. A medium of 
4-io nutrient bouillon containing 0.1 per cent of lead-acetate crystals was also inocu¬ 
lated with the organism. Although growth took place moderately, no precipitate 
of lead sulphid occurred in five weeks. 
Methylene-blue in milk. —There is a very slow reduction of methylene-blue in 
milk. The organism was inoculated into tubes containing a milk medium to which 
4 per cent of a 1 per cent solution of methylene-blue had been added. Slight reduc¬ 
tion was visible on the third day, and apparently took place but slightly and very 
slowly. At the end of 15 to 20 days the original color of the milk had entirely dis¬ 
appeared; the coagulum was dissolved and the whey was a pale cendre-green, with 
an upper layer of dark green. This color did not disappear, although the cultures 
were kept for five weeks. 
Saccharose bouillon.— A medium of 4-10 peptone-beef bouillon containing 5 
per cent of saccharose was inoculated. Growth was very vigorous, flocculent, and 
later formed a flaky, somewhat viscid sediment. In this medium filamentous chains 
of the organism were found. 
Aerobism. —The organism is aerobic in general; but is facultative anaerobic in the 
presence of dextrose, saccharose, or maltose. Stab cultures in tubes of 4-15 gelatin 
from which the oxygen had been removed by Wright’s method 1 showed no growth. 
Likewise poured plates of 4 " 15 gelatin showed no growth underneath sterile cover 
glasses to exclude the air (Koch's method). However, in the closed arms of fer¬ 
mentation tubes containing glucose, saccharose, or maltose bouillon there is a dis¬ 
tinctly visible growth. 
Group number. —Following the numerical system of the Society of American 
Bacteriologists, the group number is 221.3332113, 
1 Mallory F. B., and Wright, J. H. Op. cit. 
