BACTERIA DECOMPOSING CELLULOSES 191 



vibrios which were present in abundance in the water. Van Tieghem 3 

 described in detail a species of Amylobacter previously found to occur 

 in decomposing plant tissues and staining blue with iodine; it decom- 

 posed young plant tissues with the formation of butyric acid, carbon 

 dioxide and hydrogen. However, this organism was not a species in 

 the true sense of the word, but a collective form; it is doubtful whether 

 it decomposed pure cellulose at all, so that it could hardly deserve the 

 term "cellulose organism." 4 Since cellulose forms an important con- 

 stituent of manure, attention has been directed chiefly towards cellulose 

 decomposition in the rotting of manure. It has been found, for ex- 

 ample that the atmosphere at different depths of the manure pile con- 

 sists of various gases. The content of carbon dioxide and especially of 

 methane increases and the nitrogen content decreases with depth. 

 Oxygen is entirely absent at the lower depths of the pile. 



Omeliansky 5 was the first to establish definitely the connection be- 

 tween the activities of microorganisms and the decomposition of 

 cellulose. 



The following medium was employed: 



K 2 HP0 4 l.Ogram NaCl trace 



MgS0 4 0.5 gram Distilled water 1000 cc. 



(NH 4 ) 2 S0 4 or\ 



(NH 4 ) 2 HP0 4 f • 10gram 



The ammonium salt may be replaced by 0.5 per cent asparagine or 0.1 per cent 

 peptone. Some chalk and pure filter paper were placed in long-necked bottles, 

 which were then filled with the medium to the stopper. The flasks were inocu- 

 lated with horse manure or river mud and incubated at 34° to 35°. After a con- 

 siderable period of incubation (usually more than a week), gas production set in. 

 The paper became covered with specks; these were the places where the decom- 

 position of the cellulose began. At the end of the growth period (active fermenta- 

 tion), which is accompanied by abundant gas formation, there remained only a 

 part of the paper, half rotted and entirely changed in appearance. This residue 

 fell apart at the slightest touch. The white color of the paper had changed into 

 yellow-brown, the medium also was colored, and the odor of the medium was that 

 of rotten cheese. When precipitated cellulose was used in place of filter paper, 

 the reaction was more rapid. 



3 Van Tieghem, P. E. L. Sur le Bacillus amylobacter et son role dans la putre- 

 faction des tissus veg^taux. Compt. Rend. Acad. Sci. 68: 205-210; 89: 5-8> 

 1102-1104. 1879; Bull. Soc. Bot. France, 24: 128-135. 1877; 26: 25. 1879; 28: 

 243-245. 1887. 



4 Omeliansky, W. L. Die Cellulosegarung. Lafar's Handb. tech. Mykol. 

 3: 245-268. 1904. 



6 Omeliansky, W. Ueber die Garung der Cellulose. Centrbl. Bakt. II, 8: 

 193-201, 225-231, 257-263, 289-294, 321-326, 353-361, 385-391, 1902; 11: 369-377, 

 1904; 36: 472-473. 1913. 



