230 



BACILLUS OF TETANUS. 



tures lower than this. A 5 per cent, carbolic acid solution 

 destroys the spore in about fifteen hours ; a 1 per cent, solution 

 of mercuric chloride in about three hours. The addition of 



FIG. 94. 



FIG. 95. 



Bacillus tetani: six-days-old puncture 

 culture in glucose-gelatin. (Fraenkel and 

 Pfeiffer.) 



Bacillus tetani : culture four days 

 old in glucose-gelatin. (Fraenkel and 

 Pfeiffer.) 



a 0.5 per cent, aqueous solution of hydrochloric acid to these 



antiseptics hastens the destruction of the spores considerably. 



Kitasato's method for isolating the bacillus takes advantage 



of this resistance of the spores to high temperatures. Agar 



