THE SMELT AND ITS ALLIES 



233 



the apparently inexhaustible supply of this fish has been 

 immensely reduced, and the fishery will soon become 

 destroyed. 



op 



FIG. 212. Salmo fario. a. I, adipose lobe of pelvic fin ; an, anus ; c.f, caudal 

 fin ; d. f. 1, first dorsal ; d.f. 2, second dorsal or adipose fin ; 1. 1, lateral line ; 

 op, operculum ; pet. f, pectoral fin ; pv.f, pelvic fin ; v.f, ventral fin. After 

 Jardine. 



The trout, of which there are a number of kinds on both 

 continents, is commercially much less important than the 



FIG. 213. Coregonus, the lake whitefish. Much reduced. From Goode. 



salmon proper. As a result of overfishing, and the pollu- 

 tion of streams by factories and sewage, this fish is dis- 

 appearing from Eastern waters. 



