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A MANUAL OF BACTERIOLOGY 



access to an abrasion or wound of the skin in man 

 or animals, are capable of germinating there and 

 multiplying, and of producing a chemical poison, 

 which is absorbed into the system, and sets up the 

 acute complex nervous disorder called lockjaw.' 



The tetanus bacillus- (1.2 yu, long) produces spores 

 only at one end (Fig. 43), and in the spore-bearing 

 condition is known as the drum -stick -shaped 

 bacillus. It is motile and anaerobic, growing on 

 gelatine- plates (containing glucose) in an atmo- 

 sphere of hydrogen. 

 In tubes containing 

 blood serum or nutrient 

 gelatine, it grows in 

 the depth of the me- 

 dium, forming a kind 

 of cloud. The medium 

 emits a fusty smell, 

 which is characteristic 

 of this microbe. 



In obtaining culti- 

 vations of the tetanus 

 bacillus, other anaerobic microbes grow, and also pro- 

 duce spores. But Kitasato found that the tetanus 

 bacillus produced spores earlier than the other 

 bacilli present in tetanic pus. Consequently, he 

 devised the following method for separating the 

 tetanus bacillus from the other microbes : As soon 

 as spore-formation in the tetanus bacilli had com- 

 menced, the tubes (containing them) were heated 

 for a considerable time at 80 C., with the result 

 that all the bacilli were destroyed, but not the 



FIG. 43. THE TETANUS BACILLUS. 

 (x 1000.) 



