THE HABITS OF THE WATER-STRIDER 

 GERRIS REMIGES 



CHRISTINE ESSENBERG 



From the Zoological Laboratory of the University of California 



CONTENTS 



Introduction. 



General Description of Gerris Remiges. 



Locomotion. 



Food Habits. 



Cleaning Habits. 



Death Feigning. 



Phototaxis. 



Thigmotaxis. 



Rheo taxis. 



Geotaxis. 



Sense of Smell. 



Sense of Hearing. 

 General Summary. 

 Literature Cited. 



INTRODUCTION 



The purpose of this article is to report the results of obser- 

 vations made of the aquatic Hemipteran Gerris remiges. This 

 work was carried on in the Zoological Laboratory of the Uni- 

 versity of California under the direction of Professor Samuel 

 J. Holmes, to whom I am indebted for many valuable sugges- 

 tions and criticisms. I also wish to express my gratitude to 

 Professor C. E. Van Dyke for help given in determining the 

 species. 



The Gerridae, commonly known as water-striders, are of 

 world-wide distribution and include many different species. 

 The specimens were collected from small pools in Strawberry 

 Canyon, near the University Campus, Berkeley. They are 

 dark brown in color, the dorsal surface of the abdomen being 

 red. The ventral surface is usually gray and is furnished with 

 a plush-like coating which repels the water. The nymphs are 

 much shorter with bodies closely resembling those of adults, 

 but with the plush-like coating not so well developed. The 

 water-striders pass the winter as adults, hibernating under logs, 

 rocks, rubbish, and in other sheltered places. In the early 



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