412 BACTERIOLOGY. 



are frequently eliminated by the feces being derived 

 from the inflamed^ mucous surface of the intestines; 

 their growth within the intestinal canal itself, even if 

 it occurs to a limited extent, is probably not extensive. 

 Methods of Infection. With regard to the mode of 

 invasion of the typhoid bacilli, there is no doubt that 

 it is principally by way of the mouth, through the 

 stomach to the intestines. Mayer reports a particularly 

 convincing illustration of this fact in a case where death 

 ensued on the second day of the disease. On autopsy 

 were found hypersemia of the lungs, spleen, and kid- 

 ney; in the lower portion of the ileum great enlarge- 

 ment of the solitary follicles and patches of Peyer, but 

 nowhere a trace of necrosis or loss of substance; nor 

 were the mesenteric glands enlarged. Microscopically 

 an extraordinary deposit of characteristic bacilli were 

 found in the submucosa and interstitial spaces of the 

 muscles; many hundred bacilli lay in one field. On 

 the other hand, several cases are recorded in which the 

 intestinal changes were entirely wanting, and only a 

 localization of bacilli and lesions in the mesenteric 

 glands and spleen revealed the nature of the infection. 

 Inasmuch as they were present in the lymph-glands 

 which belong to the intestines, it may be assumed, 

 thinks Kruse, who reports one of these cases, that the 

 bacilli were here more rapidly absorbed than usual with- 

 out multiplying to any extent in the intestines. The 

 case mentioned by Guarnieri is also worthy of notice: 

 in this there was apparently a primary infection of the 

 gall-ducts, with no accompanying lesions in the intes- 

 tine. Bacilli were found in the blood twelve days be- 

 fore death, and on autopsy pure cultures were obtained 

 from the liver and spleen. 



