250 CLINICAL BACTERIOLOGY. 



Cultures made with them also prove equally toxic with 

 those from spores not exposed to the action of an alkaline 

 solution and of heat. The influence to which is due the 

 fact that the bacillus botulinus is incapable both of multi- 

 plying and of generating toxic metabolic products within 

 the animal body is not yet thoroughly understood. Per- 

 haps it is due to a high degree of saprophytism, which 

 does not permit the microbe to adapt itself to the animal 

 body ; and, perhaps, further, to the fact that the bodily tem- 

 perature, which is above 35 C. (95 F.), is not favorable 

 to its development. It has been shown experimentally that, 

 at a temperature of 37 C. (98.6 F.) and above, involution- 

 forms occur, and no toxin is generated. The bacillus botu- 

 linus thus occupies a position of its own. It is pathogenic 

 for human beings only by reason of its toxin, which it forms 

 outside the body upon dead substances (articles of food). 

 Van Ermengem proposes that it be designated as toxico- 

 genic. 



The toxin of botulism is to be placed upon the same 

 plane as that of diphtheria and that of tetanus. It can be 

 obtained by precipitation with alcohol, tannic acid, and 

 neutral salts. It was further separated by Brieger and 

 Kempner by treating the toxin-containing filtrate of the 

 culture according to the method proposed by Brieger and 

 Boer for diphtheria and tetanus. 



Occurrence of the Bacillus Botulinus. The organism 

 has hitherto never been observed apart from its discovery 

 by Van Ermengem in ham and in the body of a patient 

 dead of botulism. 



Mixed Infection. The associated bacteria that were 

 found together with the bacillus botulinus appear neither 

 to favor nor to inhibit the generation of toxin. 



Bacteriologic Diagnosis. Articles of food that have 

 given rise to botulism are examined by means of culture 

 (plate -procedure) for the presence of anaerobic bacteria. 

 In the case of Van Ermengem the spores of the bacillus 

 botulinus could be demonstrated in the ham microscopically. 

 These were present principally in the red portion of the 

 ham, and in smaller number in the fat. They were 

 irregularly distributed, and were entirely absent in some 

 places. In addition, it is well to inoculate animals with an 

 aqueous maceration (four parts of chopped ham and five 

 parts of water). In the bacteriologic examination of the 



