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SUMMARY OF CURRENT RESEARCHES RELATING TO 
Of asporogenous anthrax, a good number were killed ; while on sporo- 
genous anthrax there was no appreciable action. On the other bacteria 
there was no effect. 
influence of Induced Currents on the Orientation of Bacteria.* — 
Living mobile bacilli are very sensitive, says M. L. Lortet, to the 
influence of induced currents, immediately orientating themselves in the 
direction of the current ; on dead or paralysed bacilli the influence of 
electricity is nil. The method of demonstration is simple, and merely 
consists in surrounding a portion of a slide with platinum wires. Within 
this area is placed the fluid containing the bacteria and covered with a 
thin glass. The ends of the wires are connected with a Ruhmkorff’s coil, 
and as generator a bichromate of potash battery is used. Directly the 
current is started the bacteria place themselves parallel to its direction, 
no matter what course the direction may take. When killed or para- 
lysed this influence of electricity is lost. 
Conditions under which Anaerobic Bacteria can exist even in 
Presence of Oxygen.f — In mixed cultures with aerobes, says Herr W. 
Kedrowski, anaerobes thrive even with access of oxygen. According to 
Pasteur this was because the aerobes absorbed all the oxygen. Another 
possible explanation would he that the aerobes form a special fermenta- 
tive substance which renders possible the existence of anaerobes in the 
presence of oxygen. For his experiments the author used an anaerobic 
bacterium obtained from a mixture in which butyric acid fermentation 
had occurred. This organism, Clostridium butyricum , prospered along 
with some aerobes, as with Bac. prodigiosus, Bac. pyocyaneus, Sarcinse , 
yeasts, and Mic. agilis, when cultivated in bouillon to which there was 
access of air. The tetanus bacillus was also cultivated under similar 
conditions. From his own observations and those of others, the author 
concludes that the presence of aerobic bacteria imparts to anaerobes some 
faculty which enables them to grow in the presence of air. Furthermore, 
when a mixed culture of Clostr. butyricum and other anaerobes was con- 
stantly treated with oxygen, the growth of the anaerobic bacterium was 
not inhibited. This, of course, is against Pasteur’s view, and in favour 
of a fermentative substance. Experiments were then made to cultivate, 
in the filtrate of bouillon cultures of aerobic bacteria, anaerobes in the 
presence of oxygen. These experiments, however, were negative or 
uncertain. When, however, agar cultures of aerobic bacteria were killed 
with chloroform vapour, and over this bouillon infected with Clostr. 
butyricum was poured, the organism grew well in the presence of oxygen. 
Hence it seemed that the ferment of the aerobes which rendered the 
growth of the anaerobes possible had not passed through the filter in the 
former experiments ; and this suspicion was confirmed on further in- 
vestigation. The main conclusion of the author is that the cause of this 
phenomenon, viz. the thriving of anaerobes in the presence of oxygen in 
a mixed culture with aerobes, is due to the latter excreting a specific 
substance, at the expense of which the growth of the anaerobes proceeds. 
* Comptes Rendus, cxxii. (1896) pp. 892-4. 
t Zeitschr. f. Hygiene, xx. (1895) No. 3. See Centralbl. f. Bakteriol. u. Parasi- 
tenk., l te Abt., xix. (1893) pp. 470-1. 
