376 BACTERIA IN INFECTIOUS DISEASES. 



those who pursue pathological studies, are even 

 less liable to contract the diseases mentioned than 

 those members of the community who are not so 

 much exposed to infection. 



SPREADING ABSCESS IN RABBITS, Koch : 



" Coze and Feltz, Davaine, and many others, have 

 obtained in rabbits, by the injection of putrid blood, an 

 infective septicaemic disease. I have therefore repeated 

 their experiments. I have not, however, succeeded in 

 producing the effects produced by Davaine, but I ob- 

 served what others who have made similar experi- 

 ments on rabbits have already noticed that in these 

 animals the formation of an abscess constantly increas- 

 ing in extent, may occur in the subcutaneous cellular 

 tissue without any general infection taking place. Such 

 animals have at first no symptoms of disease ; a flat 

 lentiform hard infiltration at the seat of injection is all 

 that can be observed. After several days this hardness 

 extends in all directions, chiefly downwards, especially 

 towards the abdomen and anterior extremities. The 

 animal at the same time emaciates and grows feeble, 

 and dies in about twelve to fifteen days after the 

 injection. 



" The post mortem examination shows the presence, 

 in the subcutaneous tissue, of extensive flat abscesses 

 with cheesy contents ; their walls bulge in various 

 directions, though the whole remains a single cavity. 

 There is also an extreme degree of emaciation, but no 

 alteration in the peritoneum, intestine, kidney, spleen, 

 liver, heart, or lungs. In the blood the white corpus- 

 cles are greatly increased in number, but no bacteria 

 can be found. The cheesy contents consist of a finely 

 granular material, and scattered about in this are nuclei 



