FOREWORD 



"Freshwater Planarians (Turbellaria) of North America" is the 

 first of a series of identification manuals for selected taxa 

 of invertebrates occurring in freswater systems. These docu- 

 ments prepared by the Oceanography and Limnology Program, 

 Smithsonian Institution, for the Environmental Protection 

 Agency will contribute toward improving the quality of the 

 data upon which environmental decisions are based. 



Additional manuals will include, but not necessarily be limit- 

 ed to, freshwater representatives of the following groups: 

 amphipod crustaceans (Gammaridae) , branchiuran crustaceans 

 (ArguZus) , isopod crustaceans (Asellidae), decapod crayfish 

 crustaceans (Astacidae) , leeches (Hirudinea) , polychaete worms 

 (Polychaeta) , aquatic dryopoid beetles (Dryopoidea) , and 

 freshwater clams (Sphaeriacea) . 



Ill 



