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PATHOGENIC MICROORGANISMS 



vegetative forms which, occur chiefly in young cultures are slightly 

 motile and are seen to possess 4 numerous peritrichal flagella, when 

 stained by special methods. After twenty-four to forty-eight hours 

 of incubation, the length of time depending somewhat on the nature 

 of the medium and the degree of anaerobiosis, the bacilli develop 

 spores which are characteristically located at one end, giving the 

 bacterium the diagnostic drumstick appearance. 



FIG. 73. BACILLUS TETANI. Spore stain. 



As the cultures grow older the spore-bearing forms completely 

 supersede the vegetative ones. Very old cultures contain spore- 

 bearing bacilli and spores only. 



The tetanus bacillus is easily stained by the usual amlin dyes, 

 and reacts positively to Gram's stain. Flagella staining is successful 

 only when very young cultures are employed. 



Distribution. In nature, the tetanus bacillus has been found by 

 Nicolaier and others to occur in the superficial layers of the soil. 

 The earth of cultivated and manured fields seems to harbor this 



4 Vottaler, Zeit. f . Hyg., xxvii. 



