478 SPIRILLUM SPUTIGENUM. 



gelatine. On agar the cheese spirilla form a yellowish- 

 white layer ; they liquefy blood serum energetically. 

 No growth takes place on potatoes, either at the or- 

 dinary temperature or at higher temperatures. 

 Experiments By the ordinary modes of application no pathogenic 



011 animals. , . -T -IT . 



action is exerted on animals, in two experiments in 

 which the cheese spirilla were injected directly into the 

 duodenum of guinea-pigs Deneke observed no morbid 

 phenomena. Of fifteen guinea-pigs which were treated 

 by Koch in the same manner as in his experiments with 

 cholera bacilli, by previous introduction of soda solution 

 and tincture of opium, and then of pure cultivations of 

 these spirilla, three died. From these results, as well 

 as from the habitat of the spirilla, we must regard this 

 species of bacterium as a pure saprophyte. 



Deneke's experiments on animals were limited to one 

 experiment on six guinea-pigs ; into two of these cholera- 

 spirilla, into two Finkler's spirilla, and into two the cheese 

 spirilla were injected into the duodenum. The two first 

 animals died, the other four remained alive. It may be 

 remarked here, in answer to an objection by Finkler, that 

 these experiments on animals were not done on a larger scale 

 because the author knew that the same experiments were 

 being carried out at the same time in larger numbers in 

 Koch's laboratory, and because in the case of the cholera 

 bacilli more especially the results of Nicati and Bietsch and 

 of Ermengem had already been published. The result of this 

 comparative experiment permitted a judgment as to the 

 pathogenic or saprophytic nature of Finkler's and Deneke's 

 spirilla, so much the more readily because all attempts to 

 injure animals by these bacteria by the ordinary modes of 

 infection failed, and because in this case the habitat and mode 

 of spread of the organisms did not, as in the case of the 

 cholera organisms, point to a pathogenic rule which required 

 to be still further confirmed by experiments on animals. 



Spirillum sputigenum. 



Curved bacilli In the deposit on the teeth and in the saliva of man 



mouth 116 curved bacilli not uncommonly occur which have a certain 



resemblance to the cholera bacilli, but are somewhat 



larger, thinner, and more pointed at the ends. Where 



the staining with aniline dyes is not too dark, it can also 



