GLANDERS 8 I 



organism often occurs in the pus in very scanty numbers. 

 Some serum tubes should also be inoculated, as the bacillus 

 often grows badly on agar in primary cultures. The tubes 

 should be incubated three or four days before being dis- 

 carded, as growth is sometimes slow. 



The bacillus resembles that of tubercle, but is decidedly 

 thicker : it often shows the same banded staining. It is non- 

 motile, does not form spores, does not stain by Gram's method, 

 and is not acid-fast. The growth on agar is white or greyish, 

 white at first but becoming opaque and perhaps brownish. 

 In serum the growth consists of small colonies, transparent 

 at first, but afterwards opaque. The most characteristic 

 appearance is on potato, which should be inoculated from any 

 suspicious growth on the primary culture, provided micro- 

 scopic examination shows a Gram-negative bacillus in pure 

 state. The growth is abundant in forty-eight hours, and 

 forms a yellowish film, looking like honey. In a few days 

 more it darkens, becoming' chocolate-coloured. B. coli may 

 produce some pigment on potato, but hardly so much as this 

 organism. 



The most diagnostic feature, and the one which is relied on 

 chiefly in the laboratory, is the effect on a male guinea-pig, 

 when injected into the peritoneum. Acute orchitis follows 

 in two or three days, and the animal dies in a week or two. 

 Cultures should be obtained from the pus in the testes (this 

 is not difficult), and the characteristic features of the bacillus 

 recognized. 



TYPHOID FEVER 



Typhoid fever is caused by a bacillus which is variable in 

 length, though usually short (about half as long as a tubercle 

 bacillus) and thick, its length being only about three times its 

 breadth; very long forms also occur, but in small numbers. It 

 does not form spores, and it does not stain by Gram's method. 

 It is actively motile; when a culture of the organism in a fluid 

 medium is examined under the microscope, the bacilli can be 

 seen darting rapidly about in all directions. The bacillus owes 

 its motility to the possession of a large number of long wavy 

 flagella, which can only be seen after special and difficult 

 stafning processes. 



The B. coli communis, the most plentiful organism of the in- 



6 



