338 IMPORTANT VARIETIES OF FISSION-FUNGI. 



mengem, are at first characterized by a smooth edge, which 

 later develops a row of prickles, and by being composed 

 of rather coarse, refractive granules, which are in constant 

 motion. Later the border becomes much notched and 

 irregular. Gelatin is liquefied. Stab cultures are not 

 characteristic. In grape-sugar gelatin the growth is more 

 luxuriant and accompanied by more vigorous formation 

 of gas and liquefaction of gelatin; in ordinary gelatin it is 

 not characteristic. We cannot see any essential difference, 

 upon plates, between malignant edema, symptomatic an- 

 thrax, tetanus, and Bac. botulinus. 



The most important biologic properties are: while 

 grape-sugar is fermented very intensely, with accompany- 

 ing gas-formation, milk and cane-sugar are scarcely 

 affected. Milk is not coagulated. A marked foul odor 

 never occurs even upon nutrient media containing no 

 sugar, but only a sour, rancid odor. Sugar-bouillon be- 

 comes uniformly turbid, with a strong odor of butyric 

 acid. 



Optimum temperature, below 35; obligate anaerobe. 

 Growth is checked absolutely by more than 6% of chlorid 

 of sodium. The spores are killed in half an hour by a 

 temperature of 80. 



Pathogenic Properties. The organism, when intro- 

 duced by mouth or subcutaneously, produces the picture 

 of botulism, without multiplying in the body. Filtered 

 and devitalized cultures operate in the same way, since 

 toxins are formed in the cultures. Brieger and Kempner 

 have isolated the toxin, and have also obtained an anti- 

 toxin from the serum of animals which were poisoned for a 

 long time. Especially susceptible to the poisoning when 

 exhibited by mouth are guinea-pigs and mice; less, rabbits; 

 still less, rats and pigeons; and least, cats, dogs, hens. Cats 

 are also very susceptible to the subcutaneous introduc- 

 tion, but no local symptoms develop. The organism is the 

 cause of certain cases of meat poisoning in which the enteric 

 symptoms give place to nervous ones dilatation of pupil, 

 disturbances of accommodation, aphonia, paresis in the 

 region of the tongue and pharynx (paralysis of swallow- 

 ing), more rarely paresis of the extremities, and finally of 

 the muscles of respiration. Together with this are present 



