BOTULISM. 249 



These are entirely wanting in the central nerves, and almost 

 entirely in the brain. In the spinal cord the gray substance 

 is involved almost exclusively, and particularly the anterior 

 horns ; in the medulla oblongata the nuclei of the hypo- 

 glossus, the dorsal nucleus of the vagus, the middle small- 

 cell nucleus of the oculomotor nerve in short, the nuclei 

 of the cerebral nerves affected. 



Physiology of Botulism. Microscopic examination of 

 the organs and of the blood of animals dead of botulism 

 fails to disclose the presence of the bacilli anywhere ; even 

 at the site of injection they are to be found in only small 

 numbers after the lapse of three or four hours, and then 

 distinctly in process of degeneration. After intravenous 

 injection, cultures prepared from the fresh organs exhibit, 

 as early as twelve hours, only a limited number of colonies. 

 If, however, these organs are placed in the thermostat at a 

 temperature of 30 C. (86 F.), numerous microorganisms 

 can be cultivated from them after the lapse of from twelve 

 to twenty-four hours. Botulism, therefore, represents essen- 

 tially an intoxication and not a true infection. If the cul- 

 tures are freed by filtration of the bodies of the bacilli, and 

 if animals are inoculated with the toxic solution thus ob- 

 tained, precisely the same morbid manifestations are induced 

 as follow inoculation of the bacilli themselves. Van Er- 

 mengem attempted, in the same way as Vaillard and Rouget 

 in the case of tetanus, to free the spores of the layer of 

 toxin surrounding them by washing them in water, and he 

 found that the spores thus treated were much less active. 

 He was unable, however, to free the spores entirely of 

 the toxin, and he, therefore, came to the conclusion that 

 the protoplasm of the microbes must retain a certain 

 amount of toxin. 



Alkalies, and even sodium bicarbonate, destroy the toxin 

 of botulism. If spores are permitted to macerate for a 

 day in an alkaline solution that is so feeble as not to 

 destroy their germinating capability as, for instance, a 

 saturated solution of sodium bicarbonate and are then 

 exposed for two hours to a temperature of 50 C. (122 

 F.), and animals are inoculated therewith, the latter continue 

 to live. The spores, whether introduced under the skin or 

 into the stomach, are incapable of multiplying and generating 

 toxin ; outside the living body, however, the spores retain 

 the capability of generating their toxin in ordinary strength.. 



