284 SPECIFIC MICRO-ORGANISMS 



are only feebly resistant, being killed at 85C. in 15 minutes and 

 by 5 per cent carbolic acid in 24 hours. 



Strict anaerobiosis is necessary for successful culture, except 

 when B. botulinus grows in symbiosis with aerobes. Growth is 

 best at 25-30 C., very slight at 37-38.5 C., and best in a 

 medium slightly alkaline to litmus. Gelatin is quickly liquefied 

 and abundant gas is produced in glucose media. The organism 

 appears to be incapable of growth in the animal body. Cultures 

 are very poisonous when injected into or fed to animals. 



The poison "Botulin" resembles in some of its properties the 

 tetanus toxin. It is destroyed rapidly at yo -8o C., and pre- 

 serves its toxicity for years when dried. It is neutralized by 

 mixing with brain substance. It differs from the other pow- 

 erful toxins, however, in its ability to resist the gastric juice and 

 to poison by absorption through the alimentary canal. Forssman 

 has immunized guinea-pigs, rabbits and goats, and has obtained 

 an antitoxic serum from these animals. 



Botulism is a form of food poisoning definitely recognized as 

 such as early as 1820 It has followed the consumption of sau- 

 sage, hams, fish and other cured or preserved meats. The symp- 

 toms are very characteristic, appearing in 18 to 48 hours after 

 ingestion of the poisonous food. There is vomiting, dryness of 

 the mouth and constipation, motor paralysis, especially early in 

 the external ocular muscles. The involvement of the central 

 nervous system may progress to complete motor paralysis and 

 death. The mind is usually clear even in the fatal cases. This 

 disease is evidently due to the poisons already formed in the food 

 at the time it is eaten, and it is to be regarded as an intoxication 

 rather than an infection. Van Ermengem designates B. botu- 

 linus as a pathogenic saprophyte. 



