80 American Fisheries Society 



itself the sewage was still in a comparatively fresh and 

 recent state, as was shown by its still recognizable ingre- 

 dients, such as lumps of tallow, chunks of human excre- 

 ment, pieces of toilet paper, watermelon and muskmelon 

 seeds, broken grains of corn and wheat, and finely chopped 

 straw — all coming down practically unaltered through the 

 whole length of the canal. There was some development of 

 the characteristic organisms of decomposing sewage, but in 

 an insignificant amount as compared with that of the Des 

 Plaines. There were even some lake fishes in the drainage 

 canal, one a lake minnow represented by several fishes still 

 living, but in a dying state. 



Immediately below the mouth of the canal we have in the 

 Des Plaines a mingling of these waters, and in the Illinois 

 River itself, below the junction of the Des Plaines and the 

 Kankakee, the septic contributions of the former stream are 

 largely diluted by the comparatively clean water of the lat- 

 ter. Nevertheless, we had in July and August, what may be 

 called septic conditions for twenty-six miles of the course 

 of the Illinois from its origin to the Marseilles dam. 

 At Morris, which is on the middle part of this sec- 

 tion, the water, July 15, was grayish and sloppy, with foul, 

 privy odors distinguishable in hot weather. The current 

 was about four miles an hour, and the stream was in many 

 places bubbling with gases arising from the bottom. Pu- 

 trescent masses of soft, grayish or blackish, slimy matter, 

 loosely held together by threads of fungi, and densely cov- 

 ered with bell animalcules, were floating down the stream; 

 and chunks of this material, from the size of a walnut to 

 that of a milk pan, occasionally rose to the surface, evi- 

 dently borne up by the gases developing beneath them. 



The gases from the bottom sediments of the stream were 

 obtained for analysis, and were found to be identical with 

 those from septic tanks of sewage systems, composed of the 

 same elements present in similar ratios. When the analyses 

 of these river gases were brought into the same table with 

 those of gases obtained from the sludge in septic tanks of 



