EIGENMANN : FRESH WATER FISHES. 



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in common. The first group comprises the Serranidce, ScicsnidcE, Miigil- 

 idcs and Tetraodontidce. 



These are all marine families, some of which have also developed fresh- 

 water forms in Europe and North America as well as in South America. 

 The fresh-water forms of South America and Africa are local adaptations 



Range of the Haplochitonidae. 



Range of the Synbranchid^e. 

 To Illustrate the Origin of the South American Fresh-water Fish-fauna. 



