776 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
growth of B. coli commune , B. anthracis, B. pyocyaneus, B. typhi abdo- 
minalis ; that these metabolic products of the comma bacillus are the 
cause in many cases of B. coli commune not growing when cultivations 
are made on gelatin plates from the dejecta of cholera patients ; that the 
power of these metabolic products of B. cholerse asiaticse of inhibiting, 
and perhaps of quite preventing the growth of other bacteria is manifested 
in the animal organism, and occasionally renders mice immune to 
anthrax. 
Modification of Leucocytes, as the Result of Infection and Immu- 
nization.*— Mdlle. C. Everard, M. J. Demoor, and M. J. Massart have 
examined the quantitative and qualitative variations affecting leucocytes 
as the result of infection and of immunization. The microbes used were 
Vibrio metchnikovi , bacillus of hog cholera, St. pyogenes aureus , anthrax, 
B. tetani , and B. mycoides. 
The authors find that the infection of living or dead microbic cul- 
tures at first diminishes the number of leucocytes, and especially those 
with polymorphic nucleus and compact and granular protoplasm. This 
period of hypoleucocytosis is followed when the animal resists the 
infection by one of hyperleucocytosis. There is no phase of hyper- 
leucocytosis in animals which succumb. In animals which have been 
vaccinated the blood is richer in leucocytes than in fresh unvaccinated 
animals. 
The authors depict twenty-six different forms of leucocytes, all of 
which are evolution stages of the same cell; the adult leucocytes and 
that which is most powerfully phagocytic possess a polymorphic nucleus 
and a plasma charged with granules. These stages are passed through 
very rapidly, the life of a leucocyte being very ephemeral ; hence it is 
suggested that those leucocytes which impart immunity to a refractory 
animal are not those which have been affected by vaccination, but their 
descendants. 
Influenza Bacillus.] — In February 1890 Prof. 0. Bujwid made 
cultivations on oblique agar from blood drawn off from the spleen of a 
man suffering from influenza. 
After incubation for two days at 37° small colonies appeared, and 
these were found to consist of short rods or of ovoid cocci, often in twos 
or threes. The bacteria stained badly with dilute alcoholic solution of 
fuchsin. Subcultures failed, and this was thought at the time to be due 
to the rapid death of the bacteria, but Pfeiffer’s discovery renders it 
more probable that the cause was absence of hemoglobin. The first 
generation grew because some haemoglobin from the fresh blood was 
present. 
Association of Streptococcus and Bacillus typhosus.] — The fatality 
of typhoid fever is possibly often due, says Dr. H. Vincent, to a mixed 
infection, a combination of enteric fever and pyosis, the Streptococcus 
acting in conjunction with the Bacillus typhosus. This association may 
be primary, or secondary. The latter form of mixed infection is easy 
to understand, as the more or less extensive ulceration of the intestinal 
* Ann. Inst. Pasteur, vii. (1893) pp. 165-212 (1 pi.). 
f Centralbl. f. Bakttriol. u. Parasitenk., xiii. (1S93) pp. 554-5. 
X Ann. Inst. Pasteur, vii. (1893) pp. 141-64. 
