BACILLUS GASOFORMANS 339 



Agar-Agar. — Forms a greenish expansion. 

 Potatoes. — A brownish growth is rapidly formed. 



Bacillus Gasoformans. — This organism is found in water. 

 It forms small, very motile bacilli. It does not grow at 

 the higher temperatures. Cultural characters : 



Gelatine Plates. — Forms very rapidly cup-like liquefied 

 depressions. 



Gelatine Tubes. — The gelatine is rapidly liquefied. In 

 •shake-cultures much gas is formed. 



Potatoes. — Grows rapidly, producing a dark yellow, slimy 

 expansion, which afterwards becomes reddish-brown. 



Bacillus Jacinthus. — See under B. violaceous. 



Magenta Bacillus. — This organism is a very short rod, 

 which gives rise to a characteristic pigment. It is found 

 in water. Cultural characters : 



Gelatine Tubes. — Forms a streak of a brilliant carmine 

 or magenta colour. The gelatine after some time is 

 liquefied. 



Potatoes. — Similar growth to the above. After some 

 time the culture assumes the peculiar metallic lustre of 

 the aniline dyes. 



Bacillus Megatherium,— This organism was first obtained 

 from cooked cabbage leaves. It is also found in water. It 

 forms large bacilli with rounded ends, 2"5 /a broad and 

 8 to 9 /A long. It is motile, and forms Spores, giving rise 

 to clostridium-like forms, and has a great tendency to form 

 involution forms. Cultural characters : 



Gelatine Plates. — Forms small liquefying colonies, with 

 small brownish halos. 



Gelatine Tubes. — Grows very rapidly, liquefying the 

 medium in a funnel-shaped tube, until the whole of the 

 gelatine is liquefied. 



