Toxic Byproducts of Bacillus botulinus. 181 



as rendered by this method without the selective filter is in close 

 correspondence with the curves recorded by the method of 

 Einthoven. The murmurs are rendered better than by the micro- 

 phone and the disturbances due to undamped motion of dia- 

 phragm and carbon particles being absent, the murmur records 

 look less complicated. 



A more detailed description with constants of the instruments 

 and a discussion of results will be communicated after measure- 

 ments with a galvanometer of higher natural period have been 

 carried out. 



89 (1671) 



Concerning toxic byproducts of bacillus botulinus. 



By J. BRONFENBRENNER, M. J. SCHLESINGER and P. F. ORR. 



[From the Department of Preventive Medicine and Hygiene, Harvard 



Medical School.] 



Attempting to shorten the incubation period of botulinus 

 toxin by injecting gradually increasing amounts of toxin into 

 mice, one of us (Orr) has observed early that when the amount 

 of culture filtrate injected reach 0.5 c.c. animals frequently died 

 within a few minutes after injection. Further study of the nature 

 of this intoxication has brought out that when B. botulinus is 

 grown on suitable medium there are produced, in addition to the 

 specific toxin, other poisonous products. If such a culture is 

 filtered through a Berkfeld candle and the filtrate treated with 

 alcohol these secondary toxic products remain in solution. The 

 alcoholic extract equivalent to 0.5 c.c. of the original filtrate is 

 fatal when injected intraperitoneal^ into mice of 17-22 grams. 



The first symptoms are noted immediately after injection and 

 consist of restlessness and marked contraction of the abdominal 

 muscles. Within a minute or two the animal shows increased 

 response to external stimuli especially to sharp sound. Shortly 

 the animal becomes prostrated. The increased excitability per- 

 sists a few minutes longer, the respiration increases in depth and 

 decreases in frequency, and may become as infrequent as 5 

 inspirations a minute. The animal goes into coma interrupted 



