CHAPTER XV. 



THE ANTHRAX BACILLUS (BACILLUS ANTHEACIS). 



The anthrax bacillus is not only pathogenic in a great 

 many animals, but also in man, in whom it causes the 

 well-known malignant pustule. Amongst animals it 

 occurs most frequentlji in cattle, in which it only 

 exceedingly rarely remains localised to one spot, but 

 on the contrary spreads itself throughout the whole 

 body, occurring chiefly in the blood vessels. In 

 consequence, these bacilli are to be found in great 

 numbers in the blood of animals which are ill or have 

 died of this disease. 



If a drop of blood from an infected animal, which is 

 either still alive or has only just died, be placed upon 

 a slide and be examined with a moderately high 

 power ( X 300-500) of the microscope we find in- 

 numerable small glass-like rodlets distributed amongst 

 the blood corpuscles. 



These are always non-motile, and are from xoW to 

 ■^%%o mm. long, and a little over toVo mm. broad. 

 If the blood sample is not taken until some time after 

 the death of the animal, the rodlets are seen to have 



