34 



AGRICULTURAL AND INDUSTRIAL BACTERIOLOGY 



in nature, producing decomposition of organic materials. 

 One species produces the disease anthrax in animals and 

 man, and one or two species produce the diseases termed 

 foul brood of bee. 



Clostridium. The organisms of this genus are all rod- 

 shaped, producing endospores, but not growing in the pres- 

 ence of free atmospheric oxygen. Frequently the rods are 

 swollen at time of spore production, producing spindle- 

 shaped or club-shaped cells. Some of the bacteria of this 

 group are among the most active of the putrefactive forms, 



FIG. 13. CLOSTRIDIUM. A. Motile species. 1. Vegetative cells. 

 Sporulating, swollen cells, spores equatorial. B. Motile species. 

 1. Vegetative cells. 2. Sporulating cells, spores, polar, cell 

 swollen. 3. Free spores. C. Nonmotile species. 1. Vegetative 

 cells. 2. Sporulating cells, cells not swollen. 



particularly in the production of malodorous compounds 

 such as butyric acid. Other species are capable of produc- 

 ing disease, especially when introduced into wounds. 

 Among the diseases produced are gaseous gangrene in man, 

 malignant edema, blackleg, and bradsot in animals, and 

 tetanus in man and animals. 



III. FAMILY COCCACEAE 



The organisms belonging to this family have cells usually 

 spherical when free, though during division they may be 



