CHAPTER III 



CHARACTER OF THE BACILLUS OF THE GROUSE 

 DISEASE 



In the grouse disease the cultivations obtained, as 

 I said above, in almost all cases are of exactly the 

 same character, and it is these which I now proceed 

 to describe. 



(i.) Cultural characters : — 



The characters of the microbe in the gelatine plate, 

 in gelatine stab- and streak-cultivation are quite dis- 

 tinct. After 24-36 hours' incubation at 20° C. of 

 a gelatine plate, the first indications of the super- 

 ficial colonies are noticed as grey, translucent, flat, 

 angular dots, visible under a magnifying-glass. They 

 spread rapidly in breadth, so that after 3-4 days 

 they reach a diameter of 3, 5, and more millimetres ; 

 they remain flat and thin and are slightly thicker and 

 folded at the margin, which is much crenated. In 

 reflected light their aspect is whitish ; they look dry, 

 and when viewed obliquely have a fatty satiny lustre. 

 In transmitted light they look pale brown and trans- 



