342 



BACILLUS PATHOGENIC IN ANIMALS. 



Morphological 

 characters of 

 the bacilli. 



Experiments 

 with sterilised 

 earth. 



Inoculation 

 from animal 

 to animal. 



Cultivations. 



bacilli were constantly present which were somewhat 

 longer, but scarcely thicker than the bacilli of mouse septi- 

 caemia, which form at times threads, and at times irre- 

 gular groups, and which show a characteristic mode of 

 spore formation. In the first place they become more 

 or less equally thickened, then one end swells more 

 markedly, finally an oval refracting spore with sharp 

 outlines is formed at this end, while the rest of the bacil- 

 lus remains as a thin thread, three or four times thinner 

 than the spores. Numerous free spores are also usually 

 present in the preparations. The same bacilli were found 

 not only in the pus, where they were always mixed with 

 other species, but also in the immediate neighbourhood 

 of the seat of inoculation, and in the pyogenic membrane.. 



These bacilli could not be directly demonstrated in 

 the earth. That, however, micro-organisms were the 

 cause of the infective properties of the specimens of 

 earth was evident from the fact that the same specimens 

 when heated to 190 C. were completely without effect, 

 even when introduced in very large quantities. Further, 

 the disease with all its characteristic symptoms could be 

 transmitted from animal to animal. The pus proved to 

 be the most virulent material ; much smaller quantities 

 of pus than of the original earth were required ; a very 

 minute loopful of pus introduced beneath the skin was 

 sufficient to set up a more rapid and intense tetanus in 

 mice after a shorter incubation period. Under these 

 circumstances mice died in 24 to 36 hours, and rabbits 

 in 3 to 4 days. The disease could also be set up in 

 healthy mice and rabbits by inoculation with the blood 

 and organs (liver, spleen, spinal cord) of the animals 

 which had died ; but this was only successful when 

 larger quantities of the material were employed, and 

 even then the result was not constant, but only occurred 

 in about a quarter of the cases. When it occurred, 

 however, the whole group of symptoms were developed, 

 and the case terminated fatally. 



Nicolaier was able to cultivate the infective organisms 

 in blood serum at the body temperature, without, how- 

 ever, obtaining a pure cultivation. The mixture of 



