136 THE BROOK BOOK 



contrive to make these wild things consider us a 

 part of the landscape? If so, we may quietly study 

 their ways. 



Among the most frequent visitors to the surface 

 is the common "wriggler," which, they tell us, is 

 the larva of the mosquito. (None of us will ever 

 be really sure of this until we have kept some of 

 these "wagglers" in a glass of water and have seen 

 them emerge as full-fledged mosquitoes, not until 

 we have brought a few of them up "by hand.") 

 The favorite attitude of the wriggler is hanging 

 head downwards at the surface of the water. If dis- 

 turbed, it sinks with a twitch and a wriggle. It is 

 only by watching a few individuals in a small tum- 

 bler of water that one is able to discover that there 

 is near the tail a slender projection. This is the 

 breathing tube, and through it the air enters directly 

 into the tracheae. According to Dr. Howard, 

 these larvae do not voluntarily remain away from 

 the surface of the water longer than one minute. 

 The microscopic plants and animals which form the 

 principal food of the wrigglers are wafted into 

 their hungry throats by "automatic fans" which 

 wave almost constantly in front of their mouths. 



The water-tiger gets its air supply very much 

 as the wriggler does. Now and then it is forced 

 to leave off playing the role of ogre, and rise to 

 the surface for air. In order to do this it needs 

 only to let go, and the water does the rest, for its 

 body is lighter than the water. The picture shows 

 a very characteristic attitude. On the very tip 

 end of its body are two hairy appendages. These 



