176 OEIENTAL PLAGUE chap. 



heart's blood showed abundance of B. pestis. The rice- 

 fed rats both remained alive, and showed no alteration in 

 their condition. 



Experiment 10. — A guinea-pig which had been inocu- 

 lated with plague having died, its organs — bubo, spleen 

 (full of B. pestis) — were finely minced, and then mixed 

 well with wheat and flour, and placed over sulphuric acid. 

 After twenty- four hours the material, which was now 

 perfectly dry and hard, was given (June 28) as food to 

 three white and to three wild mice. 



On July 1 one of these wild mice was found dead. 

 The ileum was relaxed and full of sanguineous mucus ; 

 petechise in the mucous membrane ; mesenteric glands 

 much injected and swollen ; spleen literally packed with 

 B. pestis. The kidneys, lungs, and the liver were hardened, 

 and sections were made. In all these organs great con- 

 gestion of the blood-vessels was found, and in the large 

 and small vessels numerous B. pestis ; in the kidney some 

 of the capillaries of the Malpighian tufts were quite 

 blocked with them. 



The other two wild mice remained alive. 



Of the three white mice one was found dead on July 

 11, i.e. after thirteen days, and post-mortem examination 

 showed the following conditions : — Ileum much congested ; 

 at one spot, around a swollen more or less necrotic Peyer's 

 gland, the mucous membrane was hsemorrhagic ; the mesen- 

 teric glands swollen and hsemorrhagic ; the spleen much 

 enlarged, dark, and firm. 



Sections through the swollen Peyer's gland and sur- 

 rounding membrane showed almost complete necrosis, the 

 tissues being permeated with effused blood, and the 

 lymphatic vessels blocked with continuous masses of B. 



