852 SUMMARY OF CURRENT RESEARCHES RELATING TO 
the phagocytes of the mouse. By aid of their protection the mouse 
remains healthy until some phagocyte happens to perish, when the 
spores become free and the disease is at once set up. 
Before this view could be accepted it was necessary to find whether 
other kinds of serum having no inhibitory action exerted a less chemo- 
tactic action on the mouse phagocyte. For this purpose the serum of 
quite young rats was used, and it was found that there was absolutely 
no difference between the chemotactic activity of the young and old rat 
serum, although that of the former contains almost no alexin. Hence 
it would seem that the chemotactic activity of the serum of the adult 
rat is not the principal cause of its power of inhibiting the development 
of anthrax spores in mice, and the experiments go to show that the action 
of the phagocytes depends on the presence of alexins. 
Lupulin and Micrococcus Humuli Launensis.* — Herr A. Mohl 
finds that normal lupulin grains always contain an innumerable 
quantity of micrococci, M. Humuli Launensis , while other organisms, 
(bacteria, &c.) have not been detected. In the oil and resin cells the 
micrococcus is either absent or very infrequent. 
Bacillus typhi murium and the Mouse Plague.j — Prof. F. 
Loeffler narrates his experiences in Thessaly whither he had been 
summoned by the Greek Government to put down the plague of field 
mice with which that part of Greece has been devastated. The author 
recounts at some length his adventures and the successful issue of the 
experiments, which had hitherto not been tried on a large scale, although 
the fact that field mice were killed after eating fodder soaked with 
cultivations of Bacillus typhi murium had been known since the publi- 
cation of the author’s original paper some eighteen months ago. In 
that communication + it was further shown that this bacillus was patho- 
genic only to field and house mice, all other animals being quite un- 
affected by it, and it was then suggested that this micro-organism 
might be used for combating the extraordinary hordes of field mice 
which sometimes occur in certain countries. On arriving in Greece 
the author found that the Thessalian field mice differed in many re- 
spects from Arvicola arvalis, the French Campagnol ; it was larger, 
of a lighter colour, with large bright eyes and an unusually short tail. 
Its track marks were much more distinct than those of the German 
field mouse. It was necessary, therefore, to ascertain if B. typhi murium 
were pathogenic to this particular field mouse. This question was soon 
settled in the affirmative, for the injected mice died in from 2-4 days, 
and the fed mice in from 5^-7 days, and the morbid appearances were 
identical with those of mouse typhus. The author then describes how 
cultivations of the micro-organisms were made on a large scale; the 
medium was oat or barley straw decoction to which 1 per cent, pepton 
and 1/2 per cent, grape sugar had been added. The decoction was neutra- 
lized with soda, and having been placed in large vessels each holding 
60 litres, was steam sterilized. In case of accidents some 400 agar tube 
* Oesterr. Landw. Centralbl., 1892. See Centralbl. f. Bakteriol. u. Parasitenk., 
xii. (1892) p. 32. 
t Centralbl. f. Bakteriol. u. Parasitenk., xii. (1892) pp. 1-17. 
X Cf. ante, p. 280. 
