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 hyperemia 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. 
