126 PROC. ENT. SOC. WASH., VOL. 24, NO. 5, MAY, 1922 



but still giving the appearance of being hurt. I watched it 

 fully a minute, wondering what ailed it, when it suddenly 

 righted itself and ran rapidly and nervously about, showing 

 it was not in the least injured. But it almost immediately 

 went through the same performance of lying on the side and 

 kicking the legs, the posterior ones moving the most. Soon it 

 again got to its feet and ran to the edge of the stone where a 

 large leaf was floating flat on the surface of the water. To 

 my surprise it deliberately crawled beneath this floating leaf 

 and out of sight. I failed to see just when or where it emerged 

 but soon it was again on the stone and going through its queer 

 actions. Then, after taking a short but very active flight for 

 a few feet, it did the most interesting thing of all. It alighted 

 near the edge of the same stone and crawled deliberately down 

 the edge into the water, which, as stated before, was about 

 three inches deep, and ran across the bottom, moving freely 

 but not nearly so fast as when on top of the rock in the open 

 air. It crossed the narrow channel to another stone, a distance 

 of about one-half foot, where it came to the surface by climbing 

 up the edge of that stone. 1 After again going through its kicking 

 performance it flew across the pool with the legs and apparently 

 the tips of its wings touching the surface of the water. It 

 then ran along for some distance on the surface of the pool 

 somewhat after the manner of a water-strider, but the wings, 

 I think, vibrating rapidly all the time. Fearing it would leave 

 the vicinity I then swatted it with a bunch of weeds, as I had 

 no net, knocked it down and caught it, injuring it somewhat 

 in doing so." 



The above notes were written the same day the observations 

 were made, and essentially as here presented. 



BOOK NOTICE. 



An Introduction to Cytology. By Lester W. Sharp. New York, McGraw- 

 Hill Book Co., 1921. 



Intended, on the animal side, as supplementary to Wilson's well known work, 

 this book brings into one volume the more recent phases of both plant and 

 animal cytology. For this reason it will be of special interest to the entomolo- 

 gist whose field includes not only the nature of the insects themselves but their 

 relation to the tissues of the plants on which they feed. EDITOR. 



'This probably explains why its emergence from beneath the floating leaf 

 was unobserved, as it probably went to the bottom of the pool on that occasion, 

 and perhaps ran around co the opposite side of the stone before coming to 

 the surface. 



Actual date of publication, May 26, 1V22. 



