208 TEXT-BOOK OF BACTERIOLOGY. 



glomeruli and in the villi of the intestines, and also in the mucous 

 membrane of the stomach and in the salivary glands. This is, 

 however, most frequent in the glomeruli. Many of them are burst 

 and the rod-cells pass into the uriniferous tubules, yet they do not 

 penetrate far. Koch says : " I have only found them in the first 

 portion of the convoluted tube, in which they grow to long threads 

 which become felted into each other. In the straight tubes, on the 

 other hand, I have never met with the bacilli." 



In a second class of cases the lungs form the door of entrance 

 for the bacteria, and the virus is received in respiration. The par- 

 ticulars of this process we owe chiefly to the investigations of H. 

 Buchner. He caused animals to inhale anthrax spores, and found 

 that the majority of them perished from typical splenic fever. The 

 germs had found a resting-place in the tissue of the lungs, had 

 penetrated the uninjured surface of the alveolar mucous mem- 

 brane, and then passed over from their first settlement outside 

 the vessels into the blood and juices, where they increased in the 

 manner already observed, and caused a general septicaemic infec- 

 tion of the whole organism. In the lungs themselves only slight 

 alterations are visible in this kind of infection, scarcely sufficient to 

 indicate that the entire affection took its commencement from this 

 point. 



But the matter is very different when, instead of spores, bacilli 

 are introduced into the respiratory passages. While the former at 

 first produce no striking effects, the latter (the bacilli) act on the 

 tissue from the very beginning as a decided irritant, and thus a 

 very violent pneumonia is easily produced. The pulmonary vesi- 

 cles fill with exuded serous or sero-fibrinous fluid, in which large 

 quantities of anthrax bacilli are balled together. The walls of the 

 alveoli are also oedematous, but seldom become a habitation for 

 the invaders. As a rule, no general infection follows the first local 

 infection. 



Lastly, the anthrax bacilli are also able to enter with the food 

 and commence their attack from the intestinal canal. The bacilli, 

 indeed, are always killed by the acid gastric juice, and the micro- 

 organisms can reach the intestines only in the form of spores. In 

 the alkaline contents of the intestines they find sufficient nourish- 

 ment, and also a suitable temperature in which to germinate and 

 increase. They adhere to the epithelial lining of the intestines and 

 become attached to the villi, where they form complete coatings or 

 dense masses. Then the epithelium is pushed aside, the cells pen- 

 etrate into the deeper recesses, into the parenchyma of the mucous 

 membrane, get into the lymph passages or direct into the blood- 



