THE WHIRLIGIG WATER-BEETLE 307 



in the smooth and sunny bays all along the brook. 

 This is something new to me. They seem to be more 

 ready than usual to dive to the bottom when disturbed. 

 At night, of course, they dive to the bottom and bury 

 themselves, and if in the morning they perceive no cur- 

 tain of ice drawn over their sky, and the pleasant weath- 

 er continues, they gladly rise again and resume their 

 gyrations. I think I never noticed them more numer- 

 ous. What a funny way. they have of going to bed! 

 They do not take a light and go up-stairs ; they go be- 

 low. Suddenly it is heels up and heads down, and they 

 go to their muddy bed, and let the unresting stream 

 flow over them in their dreams. 



" Sometimes they seem to have a little difficulty in 

 making the plunge. Maybe they are too dry to slip 

 under. Suppose you were to trace the course of one 

 for a day, what kind of a figure would it make ? I see 

 one chasing a mote, and the wave the creature makes 

 always causes the mote to float away from it. I would 

 like to know what it is they communicate to one an- 

 other ; they, who appear to value each other's society 

 so much. How many water-bugs make a quorum? 

 Where did they get their backs polished so ?" 



It is true, as Thoreau says, that they do not take a 

 candle and go up-stairs to bed as some bigger folks do ; 

 but if he supposed that they went to bed without a 

 light, he little knew the bug he describes, for they carry 

 a brilliant lantern that goes gleaming like a silver streak 

 down into the depths ; for when those little " heels go 

 up " a bubble of air is caught beneath the tips of the 

 black wing-covers, and a diamond of pure sunlight ac- 

 companies their course down among the weeds until 

 they once more ascend to the surface. Indeed, this 



