582 APPLICATION OF METHODS OF BACTERIOLOGY 



It is stained by the ordinary aniline staining-reagents. 

 It retains the color when stained by Gram's method. 



Cultural Peculiarities. — It is an 

 ^"^- I'^i obligate anaerobe, and cannot be 



brought to development under access 

 of oxygen. It thrives in an atmos- 

 phere of pure hydrogen, but not in 

 one of carbonic acid. 



It grows in ordinary nutrient 

 gelatin and agar-agar of a slightly 

 alkaline reaction. Gelatin is slowly 

 liquefied, with the coincident pro- 

 duction of a small amount of gas. 

 Blood-serum is not liquefied by its 

 growth. 



The addition to the media of from 

 1.5 to 2 per cent, of glucose^ 0.1 

 per cent, of indigo-sodium sulphate, 

 or 5 per cent, by volume of blue 

 litmus tincture favors its growth. 



It grows well in alkaline bouillon 

 under an atmosphere of hydrogen. 



Under artificial conditions it may 

 be cultivated through numerous gene- 

 rations without loss of virulence. 



Appearance of the Colonies. — Colo- 

 nies of bacillus tetani on gelatin under 

 an atmosphere of hydrogen have, 

 in their early stages, somewhat the 

 appearance of the colonies of the 

 common bacillus subtilis in their 

 earliest stages, viz., they have it 



Colonies of the tetanus 

 bacillus four days old, 

 made by distributing the 

 organisms through a tube 

 nearly filled with glucose- 

 gelatin. Cultivation in 

 an atmosphere of hydro- 

 gen. (From Frankel and 

 Pfeiffer.) 



