CHAPTER XII 



PATHOGENIC BACILLI : GROUP C 



As belonging to this group we consider pathogenic bacilli 

 which in morphological and cultural respects differ from 

 those hitherto considered. They are fine cylindrical rods 

 of about o '8 to I /A long, o'l to o'2 /jt, thick, forming charac- 

 teristic translucent, filamentous, gelatinous growths, slowly 

 liquefying gelatine and not forming spores. 



I. Bacillus of mouse septicemia of Koch. — By inoculation 

 of filthy water into mice Koch produced a fatal and acute 

 septicaemia, which owing to the peculiar microbe has great 

 interest. At the seat of the inoculated animals there is 

 found slight hsemorrhage, the internal viscera are greatly 

 congested, the spleen is not much enlarged ; the animals 

 die during the second day. In the blood of all parts are 

 found in very large numbers exceedingly minute bacilli, 

 some longer than others, but all very fine ; many of the 

 white blood-corpuscles are quite filled with them, being at 

 the same time swollen up. In the lungs there is slight 

 haemorrhage into the alveolar tissue : everywhere one sees 

 the swollen leucocytes completely filled with the minute 

 bacilli, some of these also free owing to the disintegration 

 of the leucocytes. Sections stained carefully in fuchsin and 



