No. 631] 



ANIMAL LIFE AND SEWAGE 



161 



which would have made a difference in the number from 

 the standpoint of pollution. This has been done by 

 Forbes and Richardson in their studies of the Illinois 

 River pollution. 6 



A comparison of the report made by Engineer E. 

 Kuichling, Feb. 1, 1907 (1913 report, pp. 5-42) with that 

 of Mr. Whipple made in 1912 shows in a striking manner 

 the rapid increase of polluted conditions, the former au- 

 thor describing conditions as not very bad (pp. 10-11) 

 while the latter author, five years later, describes the con- 

 ditions as very bad (p. 182). It was between these dates, 

 1907 and 1912, that the molluscan fauna disappeared and 

 it is apparent that the distinct increase in toxicity is in- 

 dicated from these several angles of vision. 



It should be stated in connection with the ill effects of 

 sewage pollution that it affects the population in an indi- 

 rect manner not usually recognized by sanitary engineers 

 who have not interested themselves in the problem of fish 

 culture. Such places as the six miles of shallow shore 

 bordering the Genesee Eiver are the breeding and feed- 

 ing ground of such valuable food and game fish as the 

 sturgeon, black bass, sunfish, suckers, bullheads, pickerel, 

 pike, etc., and the young of these and other fish spend a 

 large part of their life in this kind of a habitat, to later 

 migrate into the open lake. 



rpper Illinois River," Bull. IUinois 

 [X, pp. 481-574, 1913. 



