SPECIAL BACTERIOLOGY 
151 
(The rabbit was injected with typhoid bacilli, and his 
blood serum showed the following agglutination, in 
various dilution of blood serum with salt solution.) 
Dilution 
1:100 
1:200 
1:500 1:1000 
1:3000 
Typhoid Bacillus . 
. 4 - 
+ 
+ 4 - 
- 1 - 
Paratyphoid Bacillus. 
. + 
+ 
4 - — 
Colon Bacillus . 
. 4 - 
— 
-t-= Agglutination takes place. 
—— Agglutination does not take place. 
This table shows that the blood serum of a rabbit in¬ 
jected with the typhoid bacilli had developed (1) the 
major or typhoid agglutinins which agglutinated the 
typhoid bacilli in a dilution as high as 1:3000, and (2) 
minor paratyphoid agglutinin which agglutinated the 
paratyphoid bacilli in dilution up to 1:500, and (3) the 
minor colon agglutinin which agglutinated the colon 
bacilli in dilutions up to 1:100; this also shows that the 
paratyphoid bacillus are more closely related to the 
typhoid bacillus than the colon bacillus is. The technic 
of agglutinations is given in the next paragraph. 
VII. Bacteriologic Diagnosis 
Whether the culture is obtained from the blood or 
feces, plates must be made, as explained in the section on 
General Bacteriology. My method is to make the plates 
on Endo’s medium (see section on Culture Media) where 
the colon bacillus colonies are red and the typhoid colonies 
are colorless; from such a plate a colorless colony is 
picked and transferred to a Russell’s double sugar 
medium (see the section on Culture Media), inoculating 
both the surface and by stabbing; by referring to the 
table of sugar fermentations, it will be understood that 
if the culture is typhoid, only a part of the tube will 
turn from blue to red (because the typhoid bacilli 
act only on glucose, producing acid gas only), and no 
