158 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
a marked inhibitory and preventive action on the growth and deve- 
lopment of bacteria, and suggests that these substances will possibly 
be used as antiseptics. 
Fixation of Free Nitrogen by Bacilli of Root-Tubercles.* — M. Maze 
made some experiments which show that when the bacilli of the root- 
tubercles of Leguminosae are placed in a suitable medium and under con- 
ditions which correspond as nearly as possible to those in the tubercles, 
they develop in quite a surprising way, and fix free nitrogen from the air. 
Hence the fixation of nitrogen belongs to the bacillus alone, and it is no 
longer necessary to explain this fixation by means of symbiosis. 
The cultivation media were solid surface cultures, composed of an 
infusion of haricots blancs, saccharose, gelose, with some sodium chloride 
and bicarbonate. The medium was placed in thin layers in fermentation 
flasks, and air supplied by aspiration. The air was purified from nitrogen 
in combination by passing it over heated copper shavings and sulphate 
of copper, and the moisture restored by causing the air stream to bubble 
through water. The inoculation was made by means of a spraying 
pipette, so that the surface of the medium was uniformly covered with 
germs. In another series the medium was devoid of gelose, but the 
results obtained were the same, that is to say, the weight of nitrogen at 
the end of the experiment was greater than at the beginning. It was, 
therefore, proved that the bacilli of the root-tubercles of Leguminosae 
have the power of fixing the free nitrogen of the air. 
Adaptability of Bacillus radicicola to Foreign Nutritive Media, j — 
Herren A. Stutzer, R. Burri and R. Maul made experiments with 
Bacillus radicicola for the purpose of ascertaining whether it could 
adapt itself to an unaccustomed environment. After obtaining pure 
cultures from strong and healthy lucerne plants grown in a medium 
made from lucerne, grape-sugar, and gelatin, the cultures were sown on 
a medium the basis of which was white mustard. It was found that, 
after several transferences on this latter medium, B. radicicola lost its 
vitality. Success was, however, attained by gradually accustoming the 
microbe to the mustard medium, and this was done by starting with a 
lucerne medium containing 5 per cent, of mustard medium, the propor- 
tion being gradually increased until B. radicicola grew well on the pure 
mustard medium. The success of these experiments shows that B. radici- 
cola possesses a high degree of adaptibility to unaccustomed nutritive 
conditions. 
Bacteriology of Mumps. if — Messrs. P. M. Mecray and J. J. Walsh j 
examined the secretion from the parotid and the blood in some cases of 
mumps. A coccus resembling that described by Laveran and Catrin, 
occurring in pairs chieliy, but also in fours and in larger groups, and 
about the same size as the ordinary suppuration cocci, was isolated. 
The colonies are circular white shiny points, with slow growth and 
gradual liquefaction of the gelatin. On potato the growth resembles at 
first thin white streaks, gradually extending to form a thin film. On 
* Ann. Inst. Pasteur, xi. (1897) pp. 44-54. 
t Centralbl. f. Bakteriol. u. Parasitenk., 2 te Abt., ii. (1896) pp. 665-9. 
X Med. Record, Sept. 26, 1896. See Centralbl. f. Bakteriol. u. Parasitenk., l* e Abt., 
xxi. (1897) p. 68. 
