CHAPTER XL 



BACILLUS: PATHOGENIC FORMS. 



PATHOGENIC bacilli. 1 



(a) Bacillus of septicaemia of mice (Koch). By inoculating 

 ordinary house mice with minute quantities of putrid fluids 



FIG. 53. FROM A SECTION THROUGH THE LUNG OF A MOUSE DEAD OF KOCH'S 



SEPTICAEMIA. 



1. Small vessel filled with blood; the white blood-corpuscles are filled with very 



minute bacilli. 



2. Interalveolar tissue : in it a white corpuscle filled with the bacilli. Magnifying 



power 700. 



3. A white blood-corpuscle more highly magnified, 1000. 



(Stained with magenta.) 



Koch found that occasionally one or another of these animals 

 showed signs of conjunctivitis and sopor, and finally death 

 followed in about forty to sixty hours. In these cases slight 



1 What has been said of the micrococci associated with open wounds 

 and abscesses applies also to bacilli ; i.e. there are often bacilli present 

 in the secretions of open wounds, and in the tissue of the base of 

 ulcers ; and as the inflammation spreads, so also do the bacilli gradually 



