ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 
795 
This examplo showed yet once more that one must not be content 
with studying the phenomena of immunity outside the organism. This 
criticism also applied to M. Buchner’s experiments, which he had com- 
municated to this meeting; he insisted on the fact that, in order to 
assure oneself thoroughly of the bactericidal property of the serum, it 
was necessary to take a small quantity of the culture, and spread it iii 
a tube filled with serum. If, according to Dr. Buchner, one introduced a 
little of the culture wrapped in cotton-wool, the serum could no longer 
exercise its bactericidal power, and the microbe developed freely. Now, 
when one inoculated the bacillus under the skin of an animal, one 
introduced at the same time a small mass which did not spread freely in 
the blood or exudation, but remained localized at one spot. The experi- 
ments of M. Buchner, instead of furnishing an objection to the phago- 
cyte theory, rather supported it. 
Referring to the curative properties of the serum of white rats against 
anthrax, he had come to the conclusion that, whereas the living serum of 
white rats had no bactericidal action on anthrax, the dead serum of the 
same animals had marked bactericidal powers on the same micro- 
organism. When a mouse was inoculated with a mixture of the dead 
serum of a rat and anthrax bacilli, it nearly always died, although the 
disease lasted somewhat longer than usual. On examination of the point 
of inoculation it was found that the bacilli of anthrax did not grow quite 
so readily, and that an enormous number of leucocytes emigrated to the 
point of inoculation and took the bacilli into their interior and digested 
them. In tetanus, again, the leucocytes ate up considerable quantities 
of tetanus-spores and bacilli. Summing up his researches, he stated that 
whenever an animal recovered from an infectious disease this recovery 
was accompanied by a process of phagocytosis ; whenever an animal 
died of an infectious disease the process of phagocytosis was absent or 
insufficient. The theory of phagocytes was strictly based on the prin- 
ciples of evolution as laid down by Darwin and Wallace. 
Immunity to Anthrax.* — Dr. J. Sawtschenko’s experiments with 
anthrax were made on pigeons and rats, and entirely with the view of 
supporting the doctrine of phagocytosis and upsetting the results of 
Czaplewski, who found that the immunity of pigeons to anthrax was 
in no way due to phagocytosis. The author’s experiments and results 
are simply confirmatory repetitions of the experiments made by Prof. 
Metschnikoff and others, who place a very high value on the phagocyte 
for its power in producing immunity by eating up the parasites. The 
author, however, admits that complete immunity to anthrax scarcely 
exists, and that by gradually habituating the bacteria to a new medium, 
a virus is obtainable capable of killing animals previously immune to 
anthrax ; and also that anthrax bacteria disappear quite independently 
of phagocyt< s. The deciding factor in the recovery of an animal is 
the action of the phagocyte, for that the phagocytes do possess this pre- 
dominating influence is proved, says the author, from finding them 
inside the cells in enormous quantities, and very few, if any at all, 
lying free outside. Within the cells they are demonstrable by ordinary 
staining methods in varying conditions of degeneration. Yet other 
* Centralbl. f. Bakteriol. u. Parasitenk., ix. (1891) pp. 473-7, 493-6, 528-32. 
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