THE PTOMAINES. 567 



aromatic substances in certain fermentations we cannot 

 without further evidence draw conclusions as to their 

 general presence in the tissue change of other fungi, and 

 because perhaps in this direction also the individual 

 species of bacteria have a different and specific behaviour. 

 Buchner thinks that he has recently observed a totally 

 different influence of the products of tissue change in 

 the case of the cholera spirilla ; these organisms are 

 thought to develop particularly well, and better than 

 other forms of fission fungi, in a nutrient solution which 

 contains the products of the cholera spirilla obtained 

 from a previous cholera cultivation.* 



A further effect of the products of tissue change is injurious 

 their supposed action on the development of other 

 species of fission fungi. The observation that some 

 species, more especially the sensitive pathogenic forms, other bacteria. 

 rapidly die, when, at the same time, saprophytic 

 fungi have established themselves in the same nutrient 

 medium death occurring much too quickly for any 

 hurtful action by the withdrawal of nutrient material 

 can scarcely be explained otherwise than by supposing 

 that the products of the tissue change of the saprophytic 

 fungi have exerted a poisonous action on the other organ- 

 isms. Here, however, we also require more precise 

 facts, and more especially with regard to whether the 

 group of aromatic products which is common to many 

 saprophytic fungi is the important one, or whether 

 in the case of different fungi different products take part 

 in the action against the concurrent organisms. 



5. The Ptomaines. 



In investigating putrefying mixtures the discovery Ptomaine?, 

 was first made that, under the influence of bacteria, 

 nitrogenous bases arise which are, in many respects, 

 similar to the vegetable alkaloids ; some of these bodies 

 are innocuous to the higher organisms, others, however, 

 like the alkaloids, exert a poisonous action. These basic 

 bodies were found when putrefaction had gone on for some 



* Munch, arztl Intell. BL, 1835, Nr. 50. 



