BACILLUS VIOLACEUS 457 



rods of different lengths, the longer of which may be bent. 

 The rods are from 1*5 to 3'5 /-t long by 0"65 a' broad, and 

 are motile. Cultural characters : 



Gelatine Plates. — In the depth the colonies are seen as 

 small white dots, but on the surface they form small 

 grayish circular discs. After five days they are seen as 

 shining, drop-like, grayish-yellow expansions. When the 

 colonies are older, delicate concentric rings are visible in 

 and round the colony. 



Gelatine Tubes. — Forms a white expansion, which 

 gradually assumes a violet-blue colour. Afterwards the 

 growth sinks, owing to the slow liquefaction of the gelatine. 

 No pigment forms in the depth. 



Agar-Agar. — An abundant growth forms, which is yellow 

 or brownish in colour, and after a few days becomes of a 

 deep violet colour. 



Potatoes. — Forms a very deep violet expansion. 



Micrococcus Violaceus. — This organism occurs in water, 

 and in the air, etc. They occur as small, somewhat ovoid 

 cocci, in the form of streptococci. It is non-motile. Cul- 

 tural characters : 



Gelatine Plates. — Forms slimy, drop-like colonies of a 

 violet colour. 



Gelatine Tubes. — Forms a violet expansion. No lique- 

 faction of the gelatine takes place. 



Potatoes. — A violet-blue growth is formed, which after- 

 wards becomes darker in tint. 



