PREFACE 



This book began in ponds where frogs sat on the lily -pads 

 and by swift brooks from which mayflies flew forth at twi- 

 light. It originated where water plants and animals live and I 

 hope that it may be a guide into the vividness and variety of 

 their ways. Most of all I hope that it may help toward wider 

 enjoyment and fiirther acquaintance in the field of water 

 biology that offers abundant opportunity to all explorers, 

 both beginners and seasoned investigators. 



The work of making it has been done along a trail of friendli- 

 ness which will not be forgotten. Those who need a way to 

 discover the loyalty and generosity of human nature should 

 write a book about ponds and streams. 



I have borrowed freely from the writings of many biologists ; 

 some of these are named in the bibliography but lack of space 

 has excluded others whose contributions have not been small. 

 A few figures have also been borrowed and these are acknow- 

 ledged separately. Dr. J. G. Needham of Cornell University 

 first showed me how to look for things in the water; since that 

 time he has continually given me help and encouragement for 

 finding more. It is a satisfaction to have his foreword here. 

 Mrs. Margaret Tucker Saunders has read all of the manu- 

 script and has given freely of her own clear cut observations, 

 and her first hand knowledge of animals. 



Fresh water life is a vast subject and even the simplest 

 account of it must include much which can be mastered only 

 by specialists after years of study. Many who are authori- 

 ties in their fields have helped generously, by giving sugges- 



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