CLASSIFICATION BY GROUPS. 113 
1. Proteus forms. Group VI. 
2. Subtilis forms. Group VII. 
(4) Non-characteristic 
colonies on gelatin 
plates. 
1. Fermentation of 
carbohydrates. 
a. Gas production. Group VIII. 
6. Nogas production. Group IX. 
2. Non-fermentation 
of carbohydrates. Group X. 
B. Gelatin not liquefied. 
(a) Fermentation of car- 
bohydrates. 
1. Gas production. Group XI. 
2. No gas production. Group XII. 
(4) Non-fermentation of 
carbohydrates. Group XIII. 
