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This work is a textbook of fresh-water life dealing with its forms, its conditions, its fitnesses, its associations, and its economic aspects. The ecologic side of fresh-water biology is emphasized. Due consideration is given to the educational, economic, sanitary, social,... Read Full Overview

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original... Read Full Overview

This is a reproduction of a book published before 1923. This book may have occasional imperfections
such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact,
or were introduced by the scanning process. We believe... Read Full Overview

This is a reproduction of a book published before 1923. This book may have occasional imperfections
such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact,
or were introduced by the scanning process. We believe... Read Full Overview

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original... Read Full Overview

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original... Read Full Overview

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original... Read Full Overview

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact, and remains as true to the original work as possible. Therefore, you will see the original... Read Full Overview