206 



CLASSIFICATION OF THE MICBO-ORGANISMS. 



Experiments 

 on animals. 



borders. When they have reached the surface they 

 form white raised thick drops on the gelatine 1 2 mm. 

 in diameter. In the inoculation puncture the colonies 



Fig. 48. Micrococcus tetragenus. Section of lung X 800. 



become confluent, so that a thick white gelatinous mass 

 is formed along the line of puncture, and fills any 

 cracks or cavities in connection with it ; on the surface 

 a thick layer 4 5 mm. in breadth is formed. 



The minutest quantity of the cultivation inoculated 

 subcutaneously into white mice causes in all cases a 

 fatal disease. The first 2 days 

 pass by without noticeable symp- 

 toms ; then the animals become 

 still and somnolent, and after 

 8 6 days death occurs. The cocci 

 are only present in the interior 

 of the blood vessels ; in the blood 

 of the heart they are relatively 

 few in number, they are present 

 in larger numbers in the splenic 

 juice and in sections of the lungs, 



Fig. 49. Micrococcus tetra- J . 



genus. Section of, spleen in the glomeruli of the kidneys, 



x 600 ' in the liver, &c. Grey house 



mice are almost without [exception immune against M. 



