TYPHOID FEVER 109 



In size the bacillus of typhoid is about three times 

 as long as it is broad, the rods having rounded ends, 

 but with very little in its appearance to aid in its 

 identification. It is very actively motile, but the 



FIG. 18. Bacillus FIG. 19. Bacillus typhosus, 



typhosus. showing flagella. 



flagella cannot be seen without special staining 

 (Loffler's method). During life the bacilli may be 

 found in the blood, in the urine, in the rose-spots, and 

 in the feces of patients suffering with typhoid fever; 

 and after death may be found in the tissues of the 

 spleen, of the liver, of the kidneys, and of the intes- 

 tines. Colonies of typhoid bacilli show nothing es- 

 pecially characteristic, being irregular, with somewhat 

 wrinkled surfaces and a blue white color. Typhoid 

 bacilli grow best at about 35 C. (95 F.); they 

 are killed by a temperature of 60 C. (140 F.), but 

 sometimes survive freezing for weeks or even months. 

 They grow slowly, with or without oxygen, and form 

 no spores; their growth does not liquefy gelatin, 

 nor produce gaseous fermentation, nor coagulate 

 sterilized milk; these points and others are utilized 



