vii INFECTION OF ANIMALS WITH PLAGUE 167 



glands were swollen and showed punctiform haemorrhages ; 

 the mesenteric glands were swollen and showed haemor- 

 rhages ; the spleen and kidney were large and dark ; the 

 testes showed several haemorrhagic patches, and their 

 lymph vessels were injected with blood. 



Cultures, film specimens, and sections of the hardened 

 organs showed the same copious presence of B. pestis as 

 mentioned in regard of the former animals. Sections 

 through the various organs showed the same appearances 

 of distended vessels and haemorrhage, along with copious 

 presence of B. pestis, as was described in the case of rat 

 No. 1. 



Eat No. 6. — Several of the Peyer's glands of the ileum 

 were enlarged and showed haemorrhages ; mesenteric 

 glands slightly enlarged, congested ; both testes showed 

 lymph spaces and lymph vessels injected with blood; 

 the spleen was large and dark. Cultures and film 

 specimens of the Peyer's glands, of the mesenteric glands, 

 of the spleen, and of heart's blood proved to be crowded 

 with B. pestis. Sections through the various organs 

 showed appearances as in the former case. 



Here, then, there was positive result in three out of 

 four cases ; definite pathological changes of the intestine 

 with intensive and extensive distribution of B. pestis. 



Experiment 4. — Two guinea-pigs, Nos. 8 and 9, were 

 fed at the same time (May 10) and with the same stock 

 of gelatine cultures as were the rats of the previous 

 experiment ; with this difference only, that for the 

 guinea-pigs the gelatine cultures were mixed with soft 

 green food — cabbage leaves finely cut up. In all these 

 feeding experiments it was of course essential that no 

 pointed particles should be in the food, in order to obviate 



