170 OMENTAL PLAGUE chap. 



May 4 with bread mixed with minced fresh spleen of a 

 rat which had- died of typical plague after cutaneous 

 inoculation. The spleen in question was typical of 

 plague : large, dark, and crowded with B. pestis. These 

 mice remained unaffected. On May 16 they were 

 inoculated cutaneously with a trace of a gelatine culture 

 derived from the rat-spleen with which they had been fed. 

 Both were dead of typical plague on the third and fourth 

 days respectively. 



Experiment 6. — Two mice, Nos. 3 and 4, were fed on 

 May 20 with gelatine cultures of B. pestis. These 

 gelatine cultures were sixteen days old, and showed on 

 their sloped surface crowds of typical colonies, somewhat 

 dry at the margin. 



Both mice were found dead in the morning of May 24. 

 One of them must have been dead for some hours as its 

 abdomen was in an advanced state of putrefaction. But 

 the other, which was in a good state of preservation, 

 showed the following interesting appearances on post- 

 mortem examination : — In the ileum a number of hemor- 

 rhagic patches surrounding injected Peyer's glands ; 

 mesenteric glands swollen and hemorrhagic ; liver pale ; 

 spleen large, dark, and firm ; kidneys much injected. 

 Film specimens and cultures showed that the heart's blood 

 and spleen were packed with B. pestis. 



Sections through the hemorrhagic parts of the 

 intestine showed appearances similar to those already 

 described in regard of rats fed in like manner. Not only 

 was the actual infecting particle (full of B. pestis) found 

 fixed to the intestinal mucosa, that is within the lumen, 

 but the surface of the mucosa (villi) was denuded of its 

 epithelium and covered with a continuous layer of 



