352 A MANUAL OF BACTERIOLOGY 



IV. Dysentery group. 



1. Mannitol non-fermenters. B. dysenterice, Shiga. 



2. Mannitol fermenters. 



a. B. dysenterice, Strong. 



b. Sorbite fermenters. 



(a) Dextrin non-fermenters. 



(b) Dextrin fermenters. 



c. Sorbite non-fermenters. 



(a) Dextrin non-fermenters. 



(b) Dextrin fermenters. 



a. Maltose fermenters. B. dysenterice, Flexner. 

 /3. Maltose non-fermenters. B. dysenterice Y. 



The typhoid bacillus is a remarkably stable and well-defined 

 organism showing little or no variation, unlike most other members 

 of the group. 



All the foregoing are non-liquefiers ; for convenience certain 

 liquefying forms, e.g. B. cloacce, may be placed in this group. 



Typhoid Fever 



The specific organism of typhoid fever is a bacillus origi- 

 nally isolated by Eberth in 1880, and more closely studied 

 by Gafiky in 1884. 



The Eberth- Gaff ky bacillus, or Bacillus typhosus, is best 

 observed in sections of the spleen, in which it occurs in 

 groups or colonies consisting of short rods with rounded 

 ends, each measuring about 3 jm in length. It has also 

 been demonstrated in the mesenteric glands and liver, in 

 the swollen Peyer's patches before ulceration, and in 

 other situations. 



Pure cultivations may be obtained from the spleen 

 during life by puncture (p. 370), from the blood (p. 369), 

 sometimes from the urine, or from the spleen of a cadaver. 

 In the latter case the organ is washed, and then cauterised 

 lineally by means of a red-hot iron, in order to destroy 

 the saprophytic bacteria on and near the surface. An 

 incision is made with a sterilised knife through this 



