602 VITAL ACTIONS OF TEE LOWER FUNGI. 



(|3). Fermentation of the Higher Alcohols. 



Fermentation While no fermentations have been with certainty 

 alcohols^ r observed in the case of the diatomic glycol, various 

 fermentations caused by bacteria have been demonstrated 

 in the triatomic alcohol, glycerine, the tetratomic alcohol, 

 erythrite, the pentatomic alcohol, quercite, and the hexa- 

 tomic alcohols mannite and dulcite. 



Glycerine. J n the case of glycerine, Fitz observed four fermentations. 



Under the influence of the bacillus Fitzianus the morphology 

 and source of which we have discussed on page 388 glycerine 

 furnishes considerable quantities of sethylic alcohol (for ex- 

 ample, 29 grammes from 100 grammes of glycerine), and, as 

 bye-products, capronic acid, butyric acid, and a little acetic 

 acid. 



In order to set up the second fermentation, which chiefly 

 furnishes butylic alcohol, solutions of hay-water and glycerine 

 are mixed and kept at 40 C. without being previously boiled. 

 A bacillus is found in the fermenting mixture which is 2 p.. 

 broad, and 5 to 6 /*. long, and which is actively motile while 

 the fermentation is going on. In stronger solutions of glycerine 

 (above 10 per cent.) the fermentation soon ceases, and the 

 bacillus forms spores. If fresh cow-dung is sown in the 

 glycerine nutrient solution, a3thylic and butylic alcohols are 

 formed in about equal quantities (also a little propylic alcohol), 

 and, in correspondence with this, the nutrient solution is 

 peopled by two forms of bacilli. 



Thirdly, Fitz was able to set up a fermentation in glycerine 

 by means of the bacillus pyocyaneus in which large quantities 

 of butyric acid, along with a3thylic alcohol and succinic acid, 

 were obtained. 



Fourthly, as the result of the growth of small thin rods, 

 often united together in pairs, which are also able to set up 

 fermentation in malate of lime, sethylic alcohol (21 grammes 

 from 100 grammes of glycerine), and also formic acid and 

 succinic acid were obtained. A fermentation of glycerine was 

 also caused by other bacteria ; thus, as the result of the 

 growth of microcooci, alcohol, butyric acid, formic acid, and 

 acetic acid were found; Hoppe-Seyler found, on the addition 

 of putrefying fibrine to a glycerine solution, chiefly butyric 

 acid, acetic acid, and succinic acid as products of fermentation. 

 Vigna* observed the formation of set-hylic and butylic alcohol 



* Vigna, Clem. Ber., vol. xvi. 



