vni ] BACTERIUM. 



is greenish, and not lodged in the cells 

 diffusible. 



4. Pathogenic bacteria. Three kinds are descl 

 bacteria of Koch's septicaemia, of Davaine's septicaemia, and of 

 fowl-cholera. 



(a) Bacterium septiccemice (Koch). By injecting into rabbits 

 water from the rivulet Pauke, and from putrid mutton, Koch x 

 succeeded in producing a rapidly fatal septicaemia, which was 

 characterised by the following appearances : The blood of all 

 the organs contained very numerous bacteria, the spleen and 

 lymphatic glands were enlarged, and the lungs congested ; but 

 there were no extravasations and no peritonitis. The smallest 

 quantity of this blood inoculated into the skin or cornea of 

 another rabbit produced after an incubation of ten to twelve 

 hours distinct rise of temperature, and death after sixteen to 

 twenty hours. The conditions after death were the same as 

 above. Everywhere the blood contained the bacteria. They 



FIG. 33. BLOOD OF PIGEON, 

 Four blood-discs and four bacteria-termo are shown. 



are rods somewhat pointed at both ends, measuring about 

 0-0014 mm. in length and 0'0006 mm. in breadth. When 

 stained, they show at each end a deeply-tinted granule, the 

 middle part remaining unstained ; for this reason they are 

 easily mistaken for a diplococcus. Generally these rods occur 

 singly ; occasionally they form a chain of two, or more than 

 three. 



They have been cultivated successfully in beef broth, blood 

 serum, gelatine, and a mixture of gelatine and broth and 

 peptone. The cultures have the same virulent properties as 

 the original blood. 



Mice, pigeons, fowls, and sparrows are also very susceptible 

 to these bacteria ; but guinea-pigs, dogs, and rats resist them 

 successfully. 



The microbe found by Pasteur in human saliva, which he 



1 Mitth. am d. k. Gesundh. 1881. 



