94 MICRO-ORGANISMS AND DISEASE. [CHAP 



(&) Bacillus of swine plague. In a report to the medical 

 officer of the Local Government Board for 1877-1878, I have 

 shown that in this acute infectious disease the affected organs 

 contain a form of bacterium in morphological respects identical 

 with bacillus subtilis, i.e. consisting of longer or shorter motile 

 rods, capable of forming spores ; further, that artificial cultures 

 of these bacilli cause the disease in pigs after inoculation -, and 

 lastly, that mice and rabbits become affected with this disease 

 after inoculation with material directly derived from the 

 diseased organs of the pig or with artificial cultures. Last 

 year Pasteur claimed to have cultivated from the blood of the 

 pig affected with the disease a microbe which is not a bacillus, 

 but a dumb-bell micrococcus. He states that he has produced 



FIG. 58. FROM A SECTION THROUGH THE INFLAMED INGUINAL LYMPH-GLAND 



OF A PlG DEAD OF SwiNE PLAGUE. 



1 A capillary blood-vessel filled with bacilli. 



2. Reticulum of adenoid tissue. 



3. A lymph-cell. 



Magnifying power 700. (Stained with Spiller's purple.) 



with these cultures fatal illness in pigeons and rabbits, and has 

 also caused the plague in swine. I have been able to show by 

 new experiments that Pasteur is wrong in all these points. 

 First, I have proved that pigeons are altogether insusceptible 

 to the disease, since inoculations with material directly derived 

 from the diseased organs of the pig dead of swine plague, 

 material which is well known to produce the disease in the 



statement the pigeons inoculated with his cultures of the 

 dumb-bell micrococcus died with symptoms and with ana- 

 tomical lesions almost identical with those of the form of 



